Use integer[] for consistency [skip ci]

Fixed CI
Added casting [skip ci]
2026-07-22 12:07:34 +08:00 · 2024-10-13 21:15:46 -07:00 · 2024-10-13 19:52:17 -07:00 · 2024-10-13 19:46:16 -07:00 · 2024-10-13 19:45:04 -07:00 · 2024-10-13 19:33:43 -07:00
70 changed files with 2797 additions and 1389 deletions
--- a/.dockerignore
+++ b/.dockerignore
@@ -0,0 +1,8 @@
+/.git/
+/dist/
+/results/
+/tmp_check/
+/sql/vector--?.?.?.sql
+regression.*
+*.o
+*.so
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -8,29 +8,27 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - postgres: 19
-            os: ubuntu-24.04
-          - postgres: 18
-            os: ubuntu-24.04
+          # - postgres: 18
+          #   os: ubuntu-24.04
          - postgres: 17
            os: ubuntu-24.04
          - postgres: 16
-            os: ubuntu-24.04-arm
+            os: ubuntu-22.04
          - postgres: 15
            os: ubuntu-22.04
          - postgres: 14
-            os: ubuntu-22.04-arm
+            os: ubuntu-20.04
          - postgres: 13
-            os: ubuntu-22.04
+            os: ubuntu-20.04
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v4
      - uses: ankane/setup-postgres@v1
        with:
          postgres-version: ${{ matrix.postgres }}
          dev-files: true
      - run: make
        env:
-          PG_CFLAGS: -DUSE_ASSERT_CHECKING -Wall -Wextra -Werror -Wno-unused-parameter -Wno-sign-compare ${{ matrix.postgres >= 18 && '-Wno-missing-field-initializers' || '' }}
+          PG_CFLAGS: -DUSE_ASSERT_CHECKING -Wall -Wextra -Werror -Wno-unused-parameter -Wno-sign-compare
      - run: |
          export PG_CONFIG=`which pg_config`
          sudo --preserve-env=PG_CONFIG make install
@@ -48,18 +46,18 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - postgres: 18
-            os: macos-26
+          - postgres: 16
+            os: macos-14
          - postgres: 14
-            os: macos-15-intel
+            os: macos-13
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v4
      - uses: ankane/setup-postgres@v1
        with:
          postgres-version: ${{ matrix.postgres }}
      - run: make
        env:
-          PG_CFLAGS: -DUSE_ASSERT_CHECKING -Wall -Wextra -Werror -Wno-unused-parameter -Wno-unknown-warning-option ${{ matrix.postgres >= 18 && '-Wno-missing-field-initializers' || '' }}
+          PG_CFLAGS: -DUSE_ASSERT_CHECKING -Wall -Wextra -Werror -Wno-unused-parameter
      - run: make install
      - run: make installcheck
      - if: ${{ failure() }}
@@ -72,35 +70,26 @@ jobs:
          tar xf $TAG.tar.gz
          mv postgres-$TAG postgres
        env:
-          TAG: ${{ matrix.postgres == 18 && 'REL_18_2' || 'REL_14_21' }}
+          TAG: ${{ matrix.postgres == 16 && 'REL_16_2' || 'REL_14_11' }}
      - run: make prove_installcheck PROVE_FLAGS="-I ./postgres/src/test/perl -I ./test/perl"
        env:
          PERL5LIB: /Users/runner/perl5/lib/perl5
-      - run: make clean && $(brew --prefix llvm@$LLVM_VERSION)/bin/scan-build --status-bugs make
+      - run: make clean && $(brew --prefix llvm@15)/bin/scan-build --status-bugs make
        env:
-          LLVM_VERSION: ${{ matrix.os == 'macos-26' && 20 || 18 }}
          PG_CFLAGS: -DUSE_ASSERT_CHECKING
  windows:
-    runs-on: ${{ matrix.os }}
+    runs-on: windows-latest
    if: ${{ !startsWith(github.ref_name, 'mac') }}
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - postgres: 17
-            os: windows-2025
-          - postgres: 14
-            os: windows-2022
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v4
      - uses: ankane/setup-postgres@v1
        with:
-          postgres-version: ${{ matrix.postgres }}
+          postgres-version: 14
      - run: |
-          call "C:\Program Files\Microsoft Visual Studio\${{ matrix.os == 'windows-2025' && 18 || 2022 }}\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
+          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
          nmake /NOLOGO /F Makefile.win && ^
          nmake /NOLOGO /F Makefile.win install && ^
-          nmake /NOLOGO /F Makefile.win installcheck ${{ matrix.postgres != 17 && 'PG_REGRESS=$(PGROOT)\bin\pg_regress' || '' }} && ^
+          nmake /NOLOGO /F Makefile.win installcheck && ^
          nmake /NOLOGO /F Makefile.win clean && ^
          nmake /NOLOGO /F Makefile.win uninstall
        shell: cmd
@@ -133,10 +122,10 @@ jobs:
    if: ${{ !startsWith(github.ref_name, 'mac') && !startsWith(github.ref_name, 'windows') }}
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v4
      - uses: ankane/setup-postgres-valgrind@v1
        with:
-          postgres-version: 18
+          postgres-version: 16
          check-ub: yes
      - run: make OPTFLAGS=""
      - run: sudo --preserve-env=PG_CONFIG make install
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,31 +1,11 @@
-## 0.8.4 (2026-06-30)
-
- Fixed `hnsw graph not repaired` error with HNSW vacuuming
- Fixed possible error with inserts during HNSW vacuuming
-
-## 0.8.3 (2026-06-17)
-
- Fixed possible index corruption with HNSW vacuuming
- Fixed performance regression with Hamming distance and Jaccard distance with Postgres 18
-
-## 0.8.2 (2026-02-25)
-
- Fixed buffer overflow with parallel HNSW index build - [more info](https://github.com/pgvector/pgvector/issues/959)
- Improved `install` target on Windows
- Fixed `Index Searches` in `EXPLAIN` output for Postgres 18
-
-## 0.8.1 (2025-09-04)
-
- Added support for Postgres 18 rc1
- Improved performance of `binary_quantize` function
-
-## 0.8.0 (2024-10-30)
+## 0.8.0 (unreleased)

 - Added support for iterative index scans
+- Added `intvec` type
 - Added casts for arrays to `sparsevec`
- Improved cost estimation for better index selection when filtering
- Improved performance of HNSW index scans
+- Improved cost estimation
 - Improved performance of HNSW inserts and on-disk index builds
+- Reduced memory usage for HNSW index scans
 - Dropped support for Postgres 12

 ## 0.7.4 (2024-08-05)
--- a/7
+++ b/7
@@ -1,11 +1,8 @@
-# syntax=docker/dockerfile:1
-
 ARG PG_MAJOR=17
-ARG DEBIAN_CODENAME=bookworm
-FROM postgres:$PG_MAJOR-$DEBIAN_CODENAME
+FROM postgres:$PG_MAJOR
 ARG PG_MAJOR

-ADD https://github.com/pgvector/pgvector.git#v0.8.4 /tmp/pgvector
+COPY . /tmp/pgvector

 RUN apt-get update && \
 		apt-mark hold locales && \
--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
+Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group

 Portions Copyright (c) 1994, The Regents of the University of California

--- a/META.json
+++ b/META.json
@@ -2,17 +2,17 @@
 	"name": "vector",
 	"abstract": "Open-source vector similarity search for Postgres",
 	"description": "Supports L2 distance, inner product, and cosine distance",
-	"version": "0.8.4",
+	"version": "0.7.4",
 	"maintainer": [
 		"Andrew Kane <andrew@ankane.org>"
 	],
 	"license": {
-		"PostgreSQL": "https://www.postgresql.org/about/licence"
+		"PostgreSQL": "http://www.postgresql.org/about/licence"
 	},
 	"prereqs": {
 		"runtime": {
 			"requires": {
-				"PostgreSQL": "13.0.0"
+				"PostgreSQL": "12.0.0"
 			}
 		}
 	},
@@ -20,7 +20,7 @@
 		"vector": {
 			"file": "sql/vector.sql",
 			"docfile": "README.md",
-			"version": "0.8.4",
+			"version": "0.7.4",
 			"abstract": "Open-source vector similarity search for Postgres"
 		}
 	},
@@ -38,7 +38,7 @@
 	"generated_by": "Andrew Kane",
 	"meta-spec": {
 		"version": "1.0.0",
-		"url": "https://pgxn.org/meta/spec.txt"
+		"url": "http://pgxn.org/meta/spec.txt"
 	},
 	"tags": [
 		"vectors",
--- a/18
+++ b/18
@@ -1,11 +1,11 @@
 EXTENSION = vector
-EXTVERSION = 0.8.4
+EXTVERSION = 0.7.4

 MODULE_big = vector
 DATA = $(wildcard sql/*--*--*.sql)
 DATA_built = sql/$(EXTENSION)--$(EXTVERSION).sql
-OBJS = src/bitutils.o src/bitvec.o src/halfutils.o src/halfvec.o src/hnsw.o src/hnswbuild.o src/hnswinsert.o src/hnswscan.o src/hnswutils.o src/hnswvacuum.o src/ivfbuild.o src/ivfflat.o src/ivfinsert.o src/ivfkmeans.o src/ivfscan.o src/ivfutils.o src/ivfvacuum.o src/sparsevec.o src/vector.o
-HEADERS = src/halfvec.h src/sparsevec.h src/vector.h
+OBJS = src/bitutils.o src/bitvec.o src/halfutils.o src/halfvec.o src/hnsw.o src/hnswbuild.o src/hnswinsert.o src/hnswscan.o src/hnswutils.o src/hnswvacuum.o src/intvec.o src/ivfbuild.o src/ivfflat.o src/ivfinsert.o src/ivfkmeans.o src/ivfscan.o src/ivfutils.o src/ivfvacuum.o src/sparsevec.o src/vector.o
+HEADERS = src/halfvec.h src/intvec.h src/sparsevec.h src/vector.h

 TESTS = $(wildcard test/sql/*.sql)
 REGRESS = $(patsubst test/sql/%.sql,%,$(TESTS))
@@ -27,11 +27,6 @@ ifneq ($(filter ppc64%, $(shell uname -m)), )
 	OPTFLAGS =
 endif

-# RISC-V64 doesn't support -march=native
-ifeq ($(shell uname -m), riscv64)
-	OPTFLAGS =
-endif
-
 # For auto-vectorization:
 # - GCC (needs -ftree-vectorize OR -O3) - https://gcc.gnu.org/projects/tree-ssa/vectorization.html
 # - Clang (could use pragma instead) - https://llvm.org/docs/Vectorizers.html
@@ -81,9 +76,4 @@ docker:
 .PHONY: docker-release

 docker-release:
-	docker buildx build --push --pull --no-cache --platform linux/amd64,linux/arm64 --build-arg PG_MAJOR=$(PG_MAJOR) --build-arg DEBIAN_CODENAME=bookworm -t pgvector/pgvector:pg$(PG_MAJOR) -t pgvector/pgvector:pg$(PG_MAJOR)-bookworm -t pgvector/pgvector:$(EXTVERSION)-pg$(PG_MAJOR) -t pgvector/pgvector:$(EXTVERSION)-pg$(PG_MAJOR)-bookworm .
-
-.PHONY: docker-release-trixie
-
-docker-release-trixie:
-	docker buildx build --push --pull --no-cache --platform linux/amd64,linux/arm64 --build-arg PG_MAJOR=$(PG_MAJOR) --build-arg DEBIAN_CODENAME=trixie -t pgvector/pgvector:pg$(PG_MAJOR)-trixie -t pgvector/pgvector:$(EXTVERSION)-pg$(PG_MAJOR)-trixie .
+	docker buildx build --push --pull --no-cache --platform linux/amd64,linux/arm64 --build-arg PG_MAJOR=$(PG_MAJOR) -t pgvector/pgvector:pg$(PG_MAJOR) -t pgvector/pgvector:$(EXTVERSION)-pg$(PG_MAJOR) .
--- a/Makefile.win
+++ b/Makefile.win
@@ -1,9 +1,9 @@
 EXTENSION = vector
-EXTVERSION = 0.8.4
+EXTVERSION = 0.7.4

 DATA_built = sql\$(EXTENSION)--$(EXTVERSION).sql
-OBJS = src\bitutils.obj src\bitvec.obj src\halfutils.obj src\halfvec.obj src\hnsw.obj src\hnswbuild.obj src\hnswinsert.obj src\hnswscan.obj src\hnswutils.obj src\hnswvacuum.obj src\ivfbuild.obj src\ivfflat.obj src\ivfinsert.obj src\ivfkmeans.obj src\ivfscan.obj src\ivfutils.obj src\ivfvacuum.obj src\sparsevec.obj src\vector.obj
-HEADERS = src\halfvec.h src\sparsevec.h src\vector.h
+OBJS = src\bitutils.obj src\bitvec.obj src\halfutils.obj src\halfvec.obj src\hnsw.obj src\hnswbuild.obj src\hnswinsert.obj src\hnswscan.obj src\hnswutils.obj src\hnswvacuum.obj src\intvec.obj src\ivfbuild.obj src\ivfflat.obj src\ivfinsert.obj src\ivfkmeans.obj src\ivfscan.obj src\ivfutils.obj src\ivfvacuum.obj src\sparsevec.obj src\vector.obj
+HEADERS = src\halfvec.h src\intvec.h src\sparsevec.h src\vector.h

 REGRESS = bit btree cast copy halfvec hnsw_bit hnsw_halfvec hnsw_sparsevec hnsw_vector ivfflat_bit ivfflat_halfvec ivfflat_vector sparsevec vector_type
 REGRESS_OPTS = --inputdir=test --load-extension=$(EXTENSION)
@@ -31,9 +31,6 @@ LIBDIR = $(PGROOT)\lib
 PKGLIBDIR = $(PGROOT)\lib
 SHAREDIR = $(PGROOT)\share

-# Use $(PGROOT)\bin\pg_regress for Postgres < 17
-PG_REGRESS = $(LIBDIR)\pgxs\src\test\regress\pg_regress
-
 CFLAGS = /nologo /I"$(INCLUDEDIR_SERVER)\port\win32_msvc" /I"$(INCLUDEDIR_SERVER)\port\win32" /I"$(INCLUDEDIR_SERVER)" /I"$(INCLUDEDIR)"

 CFLAGS = $(CFLAGS) $(PG_CFLAGS)
@@ -57,11 +54,11 @@ install: all
 	copy $(SHLIB) "$(PKGLIBDIR)"
 	copy $(EXTENSION).control "$(SHAREDIR)\extension"
 	copy sql\$(EXTENSION)--*.sql "$(SHAREDIR)\extension"
-	if not exist "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)" mkdir "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"
+	mkdir "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"
 	for %f in ($(HEADERS)) do copy %f "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"

 installcheck:
-	"$(PG_REGRESS)" --bindir="$(BINDIR)" $(REGRESS_OPTS) $(REGRESS)
+	"$(BINDIR)\pg_regress" --bindir="$(BINDIR)" $(REGRESS_OPTS) $(REGRESS)

 uninstall:
 	del /f "$(PKGLIBDIR)\$(SHLIB)"
--- a/README.md
+++ b/README.md
@@ -11,19 +11,17 @@ Store your vectors with the rest of your data. Supports:

 Plus [ACID](https://en.wikipedia.org/wiki/ACID) compliance, point-in-time recovery, JOINs, and all of the other [great features](https://www.postgresql.org/about/) of Postgres

-Have a lot of vectors? Use [quantization](#scaling) to scale
-
 [![Build Status](https://github.com/pgvector/pgvector/actions/workflows/build.yml/badge.svg)](https://github.com/pgvector/pgvector/actions)

 ## Installation

 ### Linux and Mac

-Compile and install the extension (supports Postgres 13+)
+Compile and install the extension (supports Postgres 12+)

 ```sh
 cd /tmp
-git clone --branch v0.8.4 https://github.com/pgvector/pgvector.git
+git clone --branch v0.7.4 https://github.com/pgvector/pgvector.git
 cd pgvector
 make
 make install # may need sudo
@@ -31,21 +29,31 @@ make install # may need sudo

 See the [installation notes](#installation-notes---linux-and-mac) if you run into issues

-You can also install it with [Docker](#docker), [Homebrew](#homebrew), [PGXN](#pgxn), [APT](#apt), [Yum](#yum), [pkg](#pkg), [APK](#apk), or [conda-forge](#conda-forge), and it comes preinstalled with [Postgres.app](#postgresapp) and many [hosted providers](#hosted-postgres). There are also instructions for [GitHub Actions](https://github.com/pgvector/setup-pgvector).
+You can also install it with [Docker](#docker), [Homebrew](#homebrew), [PGXN](#pgxn), [APT](#apt), [Yum](#yum), [pkg](#pkg), or [conda-forge](#conda-forge), and it comes preinstalled with [Postgres.app](#postgresapp) and many [hosted providers](#hosted-postgres). There are also instructions for [GitHub Actions](https://github.com/pgvector/setup-pgvector).

 ### Windows

-Ensure [C++ support in Visual Studio](https://learn.microsoft.com/en-us/cpp/build/building-on-the-command-line?view=msvc-170#download-and-install-the-tools) is installed and run `x64 Native Tools Command Prompt for VS [version]` as administrator. Then use `nmake` to build:
+Ensure [C++ support in Visual Studio](https://learn.microsoft.com/en-us/cpp/build/building-on-the-command-line?view=msvc-170#download-and-install-the-tools) is installed, and run:

 ```cmd
-set "PGROOT=C:\Program Files\PostgreSQL\18"
+call "C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat"
+```
+
+Note: The exact path will vary depending on your Visual Studio version and edition
+
+Then use `nmake` to build:
+
+```cmd
+set "PGROOT=C:\Program Files\PostgreSQL\16"
 cd %TEMP%
-git clone --branch v0.8.4 https://github.com/pgvector/pgvector.git
+git clone --branch v0.7.4 https://github.com/pgvector/pgvector.git
 cd pgvector
 nmake /F Makefile.win
 nmake /F Makefile.win install
 ```

+Note: Postgres 17 is not supported yet due to an upstream issue
+
 See the [installation notes](#installation-notes---windows) if you run into issues

 You can also install it with [Docker](#docker) or [conda-forge](#conda-forge).
@@ -76,7 +84,7 @@ Get the nearest neighbors by L2 distance
 SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
 ```

-Also supports inner product (`<#>`), cosine distance (`<=>`), and L1 distance (`<+>`)
+Also supports inner product (`<#>`), cosine distance (`<=>`), and L1 distance (`<+>`, added in 0.7.0)

 Note: `<#>` returns the negative inner product since Postgres only supports `ASC` order index scans on operators

@@ -140,9 +148,9 @@ Supported distance functions are:
 - `<->` - L2 distance
 - `<#>` - (negative) inner product
 - `<=>` - cosine distance
- `<+>` - L1 distance
- `<~>` - Hamming distance (binary vectors)
- `<%>` - Jaccard distance (binary vectors)
+- `<+>` - L1 distance (added in 0.7.0)
+- `<~>` - Hamming distance (binary vectors, added in 0.7.0)
+- `<%>` - Jaccard distance (binary vectors, added in 0.7.0)

 Get the nearest neighbors to a row

@@ -215,7 +223,7 @@ L2 distance
 CREATE INDEX ON items USING hnsw (embedding vector_l2_ops);
 ```

-Note: Use `halfvec_l2_ops` for `halfvec` and `sparsevec_l2_ops` for `sparsevec` (and similar with the other distance functions)
+Note: Use `halfvec_l2_ops` for `halfvec`, `intvec_l2_ops` for `intvec`, and `sparsevec_l2_ops` for `sparsevec` (and similar with the other distance functions)

 Inner product

@@ -229,19 +237,19 @@ Cosine distance
 CREATE INDEX ON items USING hnsw (embedding vector_cosine_ops);
 ```

-L1 distance
+L1 distance - added in 0.7.0

 ```sql
 CREATE INDEX ON items USING hnsw (embedding vector_l1_ops);
 ```

-Hamming distance
+Hamming distance - added in 0.7.0

 ```sql
 CREATE INDEX ON items USING hnsw (embedding bit_hamming_ops);
 ```

-Jaccard distance
+Jaccard distance - added in 0.7.0

 ```sql
 CREATE INDEX ON items USING hnsw (embedding bit_jaccard_ops);
@@ -250,9 +258,10 @@ CREATE INDEX ON items USING hnsw (embedding bit_jaccard_ops);
 Supported types are:

 - `vector` - up to 2,000 dimensions
- `halfvec` - up to 4,000 dimensions
- `bit` - up to 64,000 dimensions
- `sparsevec` - up to 1,000 non-zero elements
+- `halfvec` - up to 4,000 dimensions (added in 0.7.0)
+- `intvec` - up to 8,000 dimensions (added in 0.8.0)
+- `bit` - up to 64,000 dimensions (added in 0.7.0)
+- `sparsevec` - up to 1,000 non-zero elements (added in 0.7.0)

 ### Index Options

@@ -306,21 +315,17 @@ Note: Do not set `maintenance_work_mem` so high that it exhausts the memory on t

 Like other index types, it’s faster to create an index after loading your initial data

-You can also speed up index creation by increasing the number of parallel workers (2 by default)
+Starting with 0.6.0, you can also speed up index creation by increasing the number of parallel workers (2 by default)

 ```sql
 SET max_parallel_maintenance_workers = 7; -- plus leader
 ```

-For a large number of workers, you may need to increase `max_parallel_workers` (8 by default)
-
-The [index options](#index-options) also have a significant impact on build time (use the defaults unless seeing low recall)
-
-Use [binary quantization](#binary-quantization) for faster build times at scale
+For a large number of workers, you may also need to increase `max_parallel_workers` (8 by default)

 ### Indexing Progress

-Check [indexing progress](https://www.postgresql.org/docs/current/progress-reporting.html#CREATE-INDEX-PROGRESS-REPORTING)
+Check [indexing progress](https://www.postgresql.org/docs/current/progress-reporting.html#CREATE-INDEX-PROGRESS-REPORTING) with Postgres 12+

 ```sql
 SELECT phase, round(100.0 * blocks_done / nullif(blocks_total, 0), 1) AS "%" FROM pg_stat_progress_create_index;
@@ -363,7 +368,7 @@ Cosine distance
 CREATE INDEX ON items USING ivfflat (embedding vector_cosine_ops) WITH (lists = 100);
 ```

-Hamming distance
+Hamming distance - added in 0.7.0

 ```sql
 CREATE INDEX ON items USING ivfflat (embedding bit_hamming_ops) WITH (lists = 100);
@@ -372,8 +377,8 @@ CREATE INDEX ON items USING ivfflat (embedding bit_hamming_ops) WITH (lists = 10
 Supported types are:

 - `vector` - up to 2,000 dimensions
- `halfvec` - up to 4,000 dimensions
- `bit` - up to 64,000 dimensions
+- `halfvec` - up to 4,000 dimensions (added in 0.7.0)
+- `bit` - up to 64,000 dimensions (added in 0.7.0)

 ### Query Options

@@ -406,7 +411,7 @@ For a large number of workers, you may also need to increase `max_parallel_worke

 ### Indexing Progress

-Check [indexing progress](https://www.postgresql.org/docs/current/progress-reporting.html#CREATE-INDEX-PROGRESS-REPORTING)
+Check [indexing progress](https://www.postgresql.org/docs/current/progress-reporting.html#CREATE-INDEX-PROGRESS-REPORTING) with Postgres 12+

 ```sql
 SELECT phase, round(100.0 * tuples_done / nullif(tuples_total, 0), 1) AS "%" FROM pg_stat_progress_create_index;
@@ -423,122 +428,34 @@ Note: `%` is only populated during the `loading tuples` phase

 ## Filtering

-There are a few ways to index nearest neighbor queries with a `WHERE` clause.
+There are a few ways to index nearest neighbor queries with a `WHERE` clause

 ```sql
 SELECT * FROM items WHERE category_id = 123 ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
 ```

-A good place to start is creating an index on the filter column. This can provide fast, exact nearest neighbor search in many cases. Postgres has a number of [index types](https://www.postgresql.org/docs/current/indexes-types.html) for this: B-tree (default), hash, GiST, SP-GiST, GIN, and BRIN.
+Create an index on one [or more](https://www.postgresql.org/docs/current/indexes-multicolumn.html) of the `WHERE` columns for exact search

 ```sql
 CREATE INDEX ON items (category_id);
 ```

-For multiple columns, consider a [multicolumn index](https://www.postgresql.org/docs/current/indexes-multicolumn.html).
-
-```sql
-CREATE INDEX ON items (location_id, category_id);
-```
-
-Exact indexes work well for conditions that match a low percentage of rows. Otherwise, [approximate indexes](#indexing) can work better.
-
-```sql
-CREATE INDEX ON items USING hnsw (embedding vector_l2_ops);
-```
-
-With approximate indexes, filtering is applied *after* the index is scanned. If a condition matches 10% of rows, with HNSW and the default `hnsw.ef_search` of 40, only 4 rows will match on average. For more rows, enable [iterative index scans](#iterative-index-scans), which will automatically scan more of the index when needed.
-
-```sql
-SET hnsw.iterative_scan = strict_order;
-```
-
-If filtering by only a few distinct values, consider [partial indexing](https://www.postgresql.org/docs/current/indexes-partial.html).
+Or a [partial index](https://www.postgresql.org/docs/current/indexes-partial.html) on the vector column for approximate search

 ```sql
 CREATE INDEX ON items USING hnsw (embedding vector_l2_ops) WHERE (category_id = 123);
 ```

-If filtering by many different values, consider [partitioning](https://www.postgresql.org/docs/current/ddl-partitioning.html).
+Use [partitioning](https://www.postgresql.org/docs/current/ddl-partitioning.html) for approximate search on many different values of the `WHERE` columns

 ```sql
 CREATE TABLE items (embedding vector(3), category_id int) PARTITION BY LIST(category_id);
 ```

-## Iterative Index Scans
-
-With approximate indexes, queries with filtering can return less results since filtering is applied *after* the index is scanned. Starting with 0.8.0, you can enable iterative index scans, which will automatically scan more of the index until enough results are found (or it reaches `hnsw.max_scan_tuples` or `ivfflat.max_probes`).
-
-Iterative scans can use strict or relaxed ordering.
-
-Strict ensures results are in the exact order by distance
-
-```sql
-SET hnsw.iterative_scan = strict_order;
-```
-
-Relaxed allows results to be slightly out of order by distance, but provides better recall
-
-```sql
-SET hnsw.iterative_scan = relaxed_order;
-# or
-SET ivfflat.iterative_scan = relaxed_order;
-```
-
-With relaxed ordering, you can use a [materialized CTE](https://www.postgresql.org/docs/current/queries-with.html#QUERIES-WITH-CTE-MATERIALIZATION) to get strict ordering
-
-```sql
-WITH relaxed_results AS MATERIALIZED (
-    SELECT id, embedding <-> '[1,2,3]' AS distance FROM items WHERE category_id = 123 ORDER BY distance LIMIT 5
-) SELECT * FROM relaxed_results ORDER BY distance + 0;
-```
-
-Note: `+ 0` is needed for Postgres 17+
-
-For queries that filter by distance, use a materialized CTE and place the distance filter outside of it for best performance (due to the [current behavior](https://www.postgresql.org/message-id/flat/CAOdR5yGUoMQ6j7M5hNUXrySzaqZVGf_Ne%2B8fwZMRKTFxU1nbJg%40mail.gmail.com) of the Postgres executor)
-
-```sql
-WITH nearest_results AS MATERIALIZED (
-    SELECT id, embedding <-> '[1,2,3]' AS distance FROM items ORDER BY distance LIMIT 5
-) SELECT * FROM nearest_results WHERE distance < 5 ORDER BY distance;
-```
-
-Note: Place any other filters inside the CTE
-
-### Iterative Scan Options
-
-Since scanning a large portion of an approximate index is expensive, there are options to control when a scan ends.
-
-#### HNSW
-
-Specify the max number of tuples to visit (20,000 by default)
-
-```sql
-SET hnsw.max_scan_tuples = 20000;
-```
-
-Note: This is approximate and does not affect the initial scan
-
-Specify the max amount of memory to use, as a multiple of `work_mem` (1 by default)
-
-```sql
-SET hnsw.scan_mem_multiplier = 2;
-```
-
-Note: Try increasing this if increasing `hnsw.max_scan_tuples` does not improve recall
-
-#### IVFFlat
-
-Specify the max number of probes
-
-```sql
-SET ivfflat.max_probes = 100;
-```
-
-Note: If this is lower than `ivfflat.probes`, `ivfflat.probes` will be used
-
 ## Half-Precision Vectors

+*Added in 0.7.0*
+
 Use the `halfvec` type to store half-precision vectors

 ```sql
@@ -547,6 +464,8 @@ CREATE TABLE items (id bigserial PRIMARY KEY, embedding halfvec(3));

 ## Half-Precision Indexing

+*Added in 0.7.0*
+
 Index vectors at half precision for smaller indexes

 ```sql
@@ -559,6 +478,16 @@ Get the nearest neighbors
 SELECT * FROM items ORDER BY embedding::halfvec(3) <-> '[1,2,3]' LIMIT 5;
 ```

+## Integer Vectors
+
+*Added in 0.8.0*
+
+Use the `intvec` type to store 8-bit integer vectors
+
+```sql
+CREATE TABLE items (id bigserial PRIMARY KEY, embedding intvec(3));
+```
+
 ## Binary Vectors

 Use the `bit` type to store binary vectors ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/imagehash/example.py))
@@ -568,16 +497,24 @@ CREATE TABLE items (id bigserial PRIMARY KEY, embedding bit(3));
 INSERT INTO items (embedding) VALUES ('000'), ('111');
 ```

-Get the nearest neighbors by Hamming distance
+Get the nearest neighbors by Hamming distance (added in 0.7.0)

 ```sql
 SELECT * FROM items ORDER BY embedding <~> '101' LIMIT 5;
 ```

+Or (before 0.7.0)
+
+```sql
+SELECT * FROM items ORDER BY bit_count(embedding # '101') LIMIT 5;
+```
+
 Also supports Jaccard distance (`<%>`)

 ## Binary Quantization

+*Added in 0.7.0*
+
 Use expression indexing for binary quantization

 ```sql
@@ -600,6 +537,8 @@ SELECT * FROM (

 ## Sparse Vectors

+*Added in 0.7.0*
+
 Use the `sparsevec` type to store sparse vectors

 ```sql
@@ -633,6 +572,8 @@ You can use [Reciprocal Rank Fusion](https://github.com/pgvector/pgvector-python

 ## Indexing Subvectors

+*Added in 0.7.0*
+
 Use expression indexing to index subvectors

 ```sql
@@ -671,10 +612,6 @@ SHOW shared_buffers;

 Be sure to restart Postgres for changes to take effect.

-### Storing
-
-Use the `halfvec` type instead of `vector` for a smaller working set.
-
 ### Loading

 Use `COPY` for bulk loading data ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/loading/example.py)).
@@ -689,8 +626,6 @@ Add any indexes *after* loading the initial data for best performance.

 See index build time for [HNSW](#index-build-time) and [IVFFlat](#index-build-time-1).

-Use [binary quantization](#binary-quantization) for smaller indexes and faster build times at scale.
-
 In production environments, create indexes concurrently to avoid blocking writes.

 ```sql
@@ -699,10 +634,10 @@ CREATE INDEX CONCURRENTLY ...

 ### Querying

-Use `EXPLAIN (ANALYZE, BUFFERS)` to debug performance.
+Use `EXPLAIN ANALYZE` to debug performance.

 ```sql
-EXPLAIN (ANALYZE, BUFFERS) SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
+EXPLAIN ANALYZE SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
 ```

 #### Exact Search
@@ -721,8 +656,6 @@ SELECT * FROM items ORDER BY embedding <#> '[3,1,2]' LIMIT 5;

 #### Approximate Search

-Use [binary quantization](#binary-quantization) with re-ranking to keep indexes in-memory at scale.
-
 To speed up queries with an IVFFlat index, increase the number of inverted lists (at the expense of recall).

 ```sql
@@ -738,20 +671,23 @@ REINDEX INDEX CONCURRENTLY index_name;
 VACUUM table_name;
 ```

-## Scaling
-
-For a smaller working set:
-
-1. Use the `halfvec` type instead of `vector` for tables
-2. Use [binary quantization](#binary-quantization) for indexes (with re-ranking for search)
-
-Scale vertically by increasing memory, CPU, and storage on a single instance. Use existing tools to [tune parameters](#tuning) and [monitor performance](#monitoring).
-
-Scale horizontally with [replicas](https://www.postgresql.org/docs/current/hot-standby.html), or use [Citus](https://github.com/citusdata/citus), [PgDog](https://github.com/pgdogdev/pgdog), or another approach for sharding ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/citus/example.py)).
-
 ## Monitoring

-Use existing tools like [pg_stat_statements](https://www.postgresql.org/docs/current/pgstatstatements.html) or [PgHero](https://github.com/ankane/pghero) to monitor performance.
+Monitor performance with [pg_stat_statements](https://www.postgresql.org/docs/current/pgstatstatements.html) (be sure to add it to `shared_preload_libraries`).
+
+```sql
+CREATE EXTENSION pg_stat_statements;
+```
+
+Get the most time-consuming queries with:
+
+```sql
+SELECT query, calls, ROUND((total_plan_time + total_exec_time) / calls) AS avg_time_ms,
+    ROUND((total_plan_time + total_exec_time) / 60000) AS total_time_min
+    FROM pg_stat_statements ORDER BY total_plan_time + total_exec_time DESC LIMIT 20;
+```
+
+Note: Replace `total_plan_time + total_exec_time` with `total_time` for Postgres < 13

 Monitor recall by comparing results from approximate search with exact search.

@@ -762,46 +698,42 @@ SELECT ...
 COMMIT;
 ```

+## Scaling
+
+Scale pgvector the same way you scale Postgres.
+
+Scale vertically by increasing memory, CPU, and storage on a single instance. Use existing tools to [tune parameters](#tuning) and [monitor performance](#monitoring).
+
+Scale horizontally with [replicas](https://www.postgresql.org/docs/current/hot-standby.html), or use [Citus](https://github.com/citusdata/citus) or another approach for sharding ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/citus/example.py)).
+
 ## Languages

 Use pgvector from any language with a Postgres client. You can even generate and store vectors in one language and query them in another.

 Language | Libraries / Examples
 --- | ---
-Ada | [pgvector-ada](https://github.com/pgvector/pgvector-ada)
-Algol | [pgvector-algol](https://github.com/pgvector/pgvector-algol)
 C | [pgvector-c](https://github.com/pgvector/pgvector-c)
 C++ | [pgvector-cpp](https://github.com/pgvector/pgvector-cpp)
 C#, F#, Visual Basic | [pgvector-dotnet](https://github.com/pgvector/pgvector-dotnet)
-COBOL | [pgvector-cobol](https://github.com/pgvector/pgvector-cobol)
 Crystal | [pgvector-crystal](https://github.com/pgvector/pgvector-crystal)
-D | [pgvector-d](https://github.com/pgvector/pgvector-d)
 Dart | [pgvector-dart](https://github.com/pgvector/pgvector-dart)
 Elixir | [pgvector-elixir](https://github.com/pgvector/pgvector-elixir)
-Erlang | [pgvector-erlang](https://github.com/pgvector/pgvector-erlang)
-Fortran | [pgvector-fortran](https://github.com/pgvector/pgvector-fortran)
-Gleam | [pgvector-gleam](https://github.com/pgvector/pgvector-gleam)
 Go | [pgvector-go](https://github.com/pgvector/pgvector-go)
 Haskell | [pgvector-haskell](https://github.com/pgvector/pgvector-haskell)
 Java, Kotlin, Groovy, Scala | [pgvector-java](https://github.com/pgvector/pgvector-java)
 JavaScript, TypeScript | [pgvector-node](https://github.com/pgvector/pgvector-node)
-Julia | [Pgvector.jl](https://github.com/pgvector/Pgvector.jl)
+Julia | [pgvector-julia](https://github.com/pgvector/pgvector-julia)
 Lisp | [pgvector-lisp](https://github.com/pgvector/pgvector-lisp)
 Lua | [pgvector-lua](https://github.com/pgvector/pgvector-lua)
 Nim | [pgvector-nim](https://github.com/pgvector/pgvector-nim)
 OCaml | [pgvector-ocaml](https://github.com/pgvector/pgvector-ocaml)
-Pascal | [pgvector-pascal](https://github.com/pgvector/pgvector-pascal)
 Perl | [pgvector-perl](https://github.com/pgvector/pgvector-perl)
 PHP | [pgvector-php](https://github.com/pgvector/pgvector-php)
-Prolog | [pgvector-prolog](https://github.com/pgvector/pgvector-prolog)
 Python | [pgvector-python](https://github.com/pgvector/pgvector-python)
 R | [pgvector-r](https://github.com/pgvector/pgvector-r)
-Racket | [pgvector-racket](https://github.com/pgvector/pgvector-racket)
-Raku | [pgvector-raku](https://github.com/pgvector/pgvector-raku)
 Ruby | [pgvector-ruby](https://github.com/pgvector/pgvector-ruby), [Neighbor](https://github.com/ankane/neighbor)
 Rust | [pgvector-rust](https://github.com/pgvector/pgvector-rust)
 Swift | [pgvector-swift](https://github.com/pgvector/pgvector-swift)
-Tcl | [pgvector-tcl](https://github.com/pgvector/pgvector-tcl)
 Zig | [pgvector-zig](https://github.com/pgvector/pgvector-zig)

 ## Frequently Asked Questions
@@ -816,11 +748,11 @@ Yes, pgvector uses the write-ahead log (WAL), which allows for replication and p

 #### What if I want to index vectors with more than 2,000 dimensions?

-You can use [half-precision vectors](#half-precision-vectors) or [half-precision indexing](#half-precision-indexing) to index up to 4,000 dimensions or [binary quantization](#binary-quantization) to index up to 64,000 dimensions. Other options are [indexing subvectors](#indexing-subvectors) (for models that support it) or [dimensionality reduction](https://en.wikipedia.org/wiki/Dimensionality_reduction).
+You can use [half-precision indexing](#half-precision-indexing) to index up to 4,000 dimensions or [binary quantization](#binary-quantization) to index up to 64,000 dimensions. Another option is [dimensionality reduction](https://en.wikipedia.org/wiki/Dimensionality_reduction).

 #### Can I store vectors with different dimensions in the same column?

-You can use `vector` as the type (instead of `vector(n)`).
+You can use `vector` as the type (instead of `vector(3)`).

 ```sql
 CREATE TABLE embeddings (model_id bigint, item_id bigint, embedding vector, PRIMARY KEY (model_id, item_id));
@@ -875,8 +807,6 @@ No, but like other index types, you’ll likely see better performance if they d
 SELECT pg_size_pretty(pg_relation_size('index_name'));
 ```

-Use [half-precision indexing](#half-precision-indexing) or [binary quantization](#binary-quantization) for smaller indexes.
-
 ## Troubleshooting

 #### Why isn’t a query using an index?
@@ -922,7 +852,7 @@ ALTER TABLE items ALTER COLUMN embedding SET STORAGE PLAIN;

 #### Why are there less results for a query after adding an HNSW index?

-Results are limited by the size of the dynamic candidate list (`hnsw.ef_search`), which is 40 by default. There may be even less results due to dead tuples or filtering conditions in the query. Enabling [iterative index scans](#iterative-index-scans) can help address this.
+Results are limited by the size of the dynamic candidate list (`hnsw.ef_search`). There may be even less results due to dead tuples or filtering conditions in the query. We recommend setting `hnsw.ef_search` to at least twice the `LIMIT` of the query. If you need more than 500 results, use an IVFFlat index instead.

 Also, note that `NULL` vectors are not indexed (as well as zero vectors for cosine distance).

@@ -934,7 +864,7 @@ The index was likely created with too little data for the number of lists. Drop
 DROP INDEX index_name;
 ```

-Results can also be limited by the number of probes (`ivfflat.probes`). Enabling [iterative index scans](#iterative-index-scans) can address this.
+Results can also be limited by the number of probes (`ivfflat.probes`).

 Also, note that `NULL` vectors are not indexed (as well as zero vectors for cosine distance).

@@ -1021,6 +951,30 @@ Function | Description | Added
 avg(halfvec) → halfvec | average | 0.7.0
 sum(halfvec) → halfvec | sum | 0.7.0

+### Intvec Type
+
+Each int vector takes `dimensions + 8` bytes of storage. Each element is a single byte signed integer. Int vectors can have up to 16,000 dimensions.
+
+### Intvec Operators
+
+Operator | Description | Added
+--- | --- | ---
+<-> | Euclidean distance | 0.8.0
+<#> | negative inner product | 0.8.0
+<=> | cosine distance | 0.8.0
+<+> | taxicab distance | 0.8.0
+
+### Intvec Functions
+
+Function | Description | Added
+--- | --- | ---
+cosine_distance(intvec, intvec) → double precision | cosine distance | 0.8.0
+inner_product(intvec, intvec) → double precision | inner product | 0.8.0
+l1_distance(intvec, intvec) → double precision | taxicab distance | 0.8.0
+l2_distance(intvec, intvec) → double precision | Euclidean distance | 0.8.0
+l2_norm(intvec) → double precision | Euclidean norm | 0.8.0
+vector_dims(intvec) → integer | number of dimensions | 0.8.0
+
 ### Bit Type

 Each bit vector takes `dimensions / 8 + 8` bytes of storage. See the [Postgres docs](https://www.postgresql.org/docs/current/datatype-bit.html) for more info.
@@ -1070,7 +1024,7 @@ l2_normalize(sparsevec) → sparsevec | Normalize with Euclidean norm | 0.7.0
 If your machine has multiple Postgres installations, specify the path to [pg_config](https://www.postgresql.org/docs/current/app-pgconfig.html) with:

 ```sh
-export PG_CONFIG=/Library/PostgreSQL/18/bin/pg_config
+export PG_CONFIG=/Library/PostgreSQL/17/bin/pg_config
 ```

 Then re-run the installation instructions (run `make clean` before `make` if needed). If `sudo` is needed for `make install`, use:
@@ -1081,11 +1035,11 @@ sudo --preserve-env=PG_CONFIG make install

 A few common paths on Mac are:

- EDB installer - `/Library/PostgreSQL/18/bin/pg_config`
- Homebrew (arm64) - `/opt/homebrew/opt/postgresql@18/bin/pg_config`
- Homebrew (x86-64) - `/usr/local/opt/postgresql@18/bin/pg_config`
+- EDB installer - `/Library/PostgreSQL/17/bin/pg_config`
+- Homebrew (arm64) - `/opt/homebrew/opt/postgresql@17/bin/pg_config`
+- Homebrew (x86-64) - `/usr/local/opt/postgresql@17/bin/pg_config`

-Note: Replace `18` with your Postgres server version
+Note: Replace `17` with your Postgres server version

 ### Missing Header

@@ -1094,20 +1048,14 @@ If compilation fails with `fatal error: postgres.h: No such file or directory`,
 For Ubuntu and Debian, use:

 ```sh
-sudo apt install postgresql-server-dev-18
+sudo apt install postgresql-server-dev-17
 ```

-Note: Replace `18` with your Postgres server version
+Note: Replace `17` with your Postgres server version

 ### Missing SDK

-If compilation fails and the output includes `warning: no such sysroot directory` on Mac, your Postgres installation points to a path that no longer exists.
-
-```sh
-pg_config --cppflags
-```
-
-Reinstall Postgres to fix this.
+If compilation fails and the output includes `warning: no such sysroot directory` on Mac, reinstall Xcode Command Line Tools.

 ### Portability

@@ -1125,14 +1073,6 @@ make OPTFLAGS=""

 If compilation fails with `Cannot open include file: 'postgres.h': No such file or directory`, make sure `PGROOT` is correct.

-### Mismatched Architecture
-
-If compilation fails with `error C2196: case value '4' already used`, make sure you’re using the `x64 Native Tools Command Prompt`. Then run `nmake /F Makefile.win clean` and re-run the installation instructions.
-
-### Missing Symbol
-
-If linking fails with `unresolved external symbol float_to_shortest_decimal_bufn` with Postgres 17.0-17.2, upgrade to Postgres 17.3+.
-
 ### Permissions

 If installation fails with `Access is denied`, re-run the installation instructions as an administrator.
@@ -1144,38 +1084,17 @@ If installation fails with `Access is denied`, re-run the installation instructi
 Get the [Docker image](https://hub.docker.com/r/pgvector/pgvector) with:

 ```sh
-docker pull pgvector/pgvector:pg18-trixie
+docker pull pgvector/pgvector:pg17
 ```

-This adds pgvector to the [Postgres image](https://hub.docker.com/_/postgres) (replace `18` with your Postgres server version, and run it the same way).
-
-Supported tags are:
-
- `pg18-trixie`, `0.8.4-pg18-trixie`
- `pg18-bookworm`, `0.8.4-pg18-bookworm`, `pg18`, `0.8.4-pg18`
- `pg17-trixie`, `0.8.4-pg17-trixie`
- `pg17-bookworm`, `0.8.4-pg17-bookworm`, `pg17`, `0.8.4-pg17`
- `pg16-trixie`, `0.8.4-pg16-trixie`
- `pg16-bookworm`, `0.8.4-pg16-bookworm`, `pg16`, `0.8.4-pg16`
- `pg15-trixie`, `0.8.4-pg15-trixie`
- `pg15-bookworm`, `0.8.4-pg15-bookworm`, `pg15`, `0.8.4-pg15`
- `pg14-trixie`, `0.8.4-pg14-trixie`
- `pg14-bookworm`, `0.8.4-pg14-bookworm`, `pg14`, `0.8.4-pg14`
- `pg13-trixie`, `0.8.4-pg13-trixie`
- `pg13-bookworm`, `0.8.4-pg13-bookworm`, `pg13`, `0.8.4-pg13`
+This adds pgvector to the [Postgres image](https://hub.docker.com/_/postgres) (replace `17` with your Postgres server version, and run it the same way).

 You can also build the image manually:

 ```sh
-git clone --branch v0.8.4 https://github.com/pgvector/pgvector.git
+git clone --branch v0.7.4 https://github.com/pgvector/pgvector.git
 cd pgvector
-docker build --pull --build-arg PG_MAJOR=18 -t myuser/pgvector .
-```
-
-If you increase `maintenance_work_mem`, make sure `--shm-size` is at least that size to avoid an error with parallel HNSW index builds.
-
-```sh
-docker run --shm-size=1g ...
+docker build --pull --build-arg PG_MAJOR=17 -t myuser/pgvector .
 ```

 ### Homebrew
@@ -1186,7 +1105,7 @@ With Homebrew Postgres, you can use:
 brew install pgvector
 ```

-Note: This only adds it to the `postgresql@18` and `postgresql@17` formulas
+Note: This only adds it to the `postgresql@17` and `postgresql@14` formulas

 ### PGXN

@@ -1201,29 +1120,29 @@ pgxn install vector
 Debian and Ubuntu packages are available from the [PostgreSQL APT Repository](https://wiki.postgresql.org/wiki/Apt). Follow the [setup instructions](https://wiki.postgresql.org/wiki/Apt#Quickstart) and run:

 ```sh
-sudo apt install postgresql-18-pgvector
+sudo apt install postgresql-17-pgvector
 ```

-Note: Replace `18` with your Postgres server version
+Note: Replace `17` with your Postgres server version

 ### Yum

 RPM packages are available from the [PostgreSQL Yum Repository](https://yum.postgresql.org/). Follow the [setup instructions](https://www.postgresql.org/download/linux/redhat/) for your distribution and run:

 ```sh
-sudo yum install pgvector_18
+sudo yum install pgvector_17
 # or
-sudo dnf install pgvector_18
+sudo dnf install pgvector_17
 ```

-Note: Replace `18` with your Postgres server version
+Note: Replace `17` with your Postgres server version

 ### pkg

 Install the FreeBSD package with:

 ```sh
-pkg install postgresql17-pgvector
+pkg install postgresql15-pgvector
 ```

 or the port with:
@@ -1233,14 +1152,6 @@ cd /usr/ports/databases/pgvector
 make install
 ```

-### APK
-
-Install the Alpine package with:
-
-```sh
-apk add postgresql-pgvector
-```
-
 ### conda-forge

 With Conda Postgres, install from [conda-forge](https://anaconda.org/conda-forge/pgvector) with:
@@ -1273,6 +1184,36 @@ You can check the version in the current database with:
 SELECT extversion FROM pg_extension WHERE extname = 'vector';
 ```

+## Upgrade Notes
+
+### 0.6.0
+
+#### Postgres 12
+
+If upgrading with Postgres 12, remove this line from `sql/vector--0.5.1--0.6.0.sql`:
+
+```sql
+ALTER TYPE vector SET (STORAGE = external);
+```
+
+Then run `make install` and `ALTER EXTENSION vector UPDATE;`.
+
+#### Docker
+
+The Docker image is now published in the `pgvector` org, and there are tags for each supported version of Postgres (rather than a `latest` tag).
+
+```sh
+docker pull pgvector/pgvector:pg16
+# or
+docker pull pgvector/pgvector:0.6.0-pg16
+```
+
+Also, if you’ve increased `maintenance_work_mem`, make sure `--shm-size` is at least that size to avoid an error with parallel HNSW index builds.
+
+```sh
+docker run --shm-size=1g ...
+```
+
 ## Thanks

 Thanks to:
@@ -1329,7 +1270,7 @@ make clean && PG_CFLAGS="-DUSE_ASSERT_CHECKING" make && make install
 To enable benchmarking:

 ```sh
-make clean && PG_CFLAGS="-DHNSW_BENCH -DIVFFLAT_BENCH" make && make install
+make clean && PG_CFLAGS="-DIVFFLAT_BENCH" make && make install
 ```

 To show memory usage:
--- a/sql/vector--0.7.4--0.8.0.sql
+++ b/sql/vector--0.7.4--0.8.0.sql
@@ -1,6 +1,188 @@
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "ALTER EXTENSION vector UPDATE TO '0.8.0'" to load this file. \quit

+CREATE FUNCTION hnsw_intvec_support(internal) RETURNS internal
+	AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE TYPE intvec;
+
+CREATE FUNCTION intvec_in(cstring, oid, integer) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_out(intvec) RETURNS cstring
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_typmod_in(cstring[]) RETURNS integer
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_recv(internal, oid, integer) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_send(intvec) RETURNS bytea
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE TYPE intvec (
+	INPUT     = intvec_in,
+	OUTPUT    = intvec_out,
+	TYPMOD_IN = intvec_typmod_in,
+	RECEIVE   = intvec_recv,
+	SEND      = intvec_send,
+	STORAGE   = external
+);
+
+CREATE FUNCTION l2_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l2_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION inner_product(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_inner_product' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION cosine_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_cosine_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION l1_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l1_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION vector_dims(intvec) RETURNS integer
+	AS 'MODULE_PATHNAME', 'intvec_vector_dims' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION l2_norm(intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l2_norm' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_lt(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_le(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_eq(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_ne(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_ge(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_gt(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_cmp(intvec, intvec) RETURNS int4
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_l2_squared_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_negative_inner_product(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec(intvec, integer, boolean) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION array_to_intvec(integer[], integer, boolean) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_to_integer(intvec, integer, boolean) RETURNS integer[]
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE CAST (intvec AS intvec)
+	WITH FUNCTION intvec(intvec, integer, boolean) AS IMPLICIT;
+
+CREATE CAST (intvec AS integer[])
+	WITH FUNCTION intvec_to_integer(intvec, integer, boolean) AS ASSIGNMENT;
+
+CREATE CAST (integer[] AS intvec)
+	WITH FUNCTION array_to_intvec(integer[], integer, boolean) AS ASSIGNMENT;
+
+CREATE OPERATOR <-> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = l2_distance,
+	COMMUTATOR = '<->'
+);
+
+CREATE OPERATOR <#> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_negative_inner_product,
+	COMMUTATOR = '<#>'
+);
+
+CREATE OPERATOR <=> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = cosine_distance,
+	COMMUTATOR = '<=>'
+);
+
+CREATE OPERATOR <+> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = l1_distance,
+	COMMUTATOR = '<+>'
+);
+
+CREATE OPERATOR < (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_lt,
+	COMMUTATOR = > , NEGATOR = >= ,
+	RESTRICT = scalarltsel, JOIN = scalarltjoinsel
+);
+
+CREATE OPERATOR <= (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_le,
+	COMMUTATOR = >= , NEGATOR = > ,
+	RESTRICT = scalarlesel, JOIN = scalarlejoinsel
+);
+
+CREATE OPERATOR = (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_eq,
+	COMMUTATOR = = , NEGATOR = <> ,
+	RESTRICT = eqsel, JOIN = eqjoinsel
+);
+
+CREATE OPERATOR <> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_ne,
+	COMMUTATOR = <> , NEGATOR = = ,
+	RESTRICT = eqsel, JOIN = eqjoinsel
+);
+
+CREATE OPERATOR >= (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_ge,
+	COMMUTATOR = <= , NEGATOR = < ,
+	RESTRICT = scalargesel, JOIN = scalargejoinsel
+);
+
+CREATE OPERATOR > (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_gt,
+	COMMUTATOR = < , NEGATOR = <= ,
+	RESTRICT = scalargtsel, JOIN = scalargtjoinsel
+);
+
+CREATE OPERATOR CLASS intvec_ops
+	DEFAULT FOR TYPE intvec USING btree AS
+	OPERATOR 1 < ,
+	OPERATOR 2 <= ,
+	OPERATOR 3 = ,
+	OPERATOR 4 >= ,
+	OPERATOR 5 > ,
+	FUNCTION 1 intvec_cmp(intvec, intvec);
+
+CREATE OPERATOR CLASS intvec_l2_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <-> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 intvec_l2_squared_distance(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_ip_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <#> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 intvec_negative_inner_product(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_cosine_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <=> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 cosine_distance(intvec, intvec),
+	FUNCTION 2 l2_norm(intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_l1_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <+> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 l1_distance(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
 CREATE FUNCTION array_to_sparsevec(integer[], integer, boolean) RETURNS sparsevec
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;

--- a/sql/vector--0.8.0--0.8.1.sql
+++ b/sql/vector--0.8.0--0.8.1.sql
@@ -1,2 +0,0 @@
-- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION vector UPDATE TO '0.8.1'" to load this file. \quit
--- a/sql/vector--0.8.1--0.8.2.sql
+++ b/sql/vector--0.8.1--0.8.2.sql
@@ -1,2 +0,0 @@
-- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION vector UPDATE TO '0.8.2'" to load this file. \quit
--- a/sql/vector--0.8.2--0.8.3.sql
+++ b/sql/vector--0.8.2--0.8.3.sql
@@ -1,2 +0,0 @@
-- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION vector UPDATE TO '0.8.3'" to load this file. \quit
--- a/sql/vector--0.8.3--0.8.4.sql
+++ b/sql/vector--0.8.3--0.8.4.sql
@@ -1,2 +0,0 @@
-- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION vector UPDATE TO '0.8.4'" to load this file. \quit
--- a/sql/vector.sql
+++ b/sql/vector.sql
@@ -272,6 +272,9 @@ CREATE FUNCTION ivfflat_bit_support(internal) RETURNS internal
 CREATE FUNCTION hnsw_halfvec_support(internal) RETURNS internal
 	AS 'MODULE_PATHNAME' LANGUAGE C;

+CREATE FUNCTION hnsw_intvec_support(internal) RETURNS internal
+	AS 'MODULE_PATHNAME' LANGUAGE C;
+
 CREATE FUNCTION hnsw_bit_support(internal) RETURNS internal
 	AS 'MODULE_PATHNAME' LANGUAGE C;

@@ -647,6 +650,199 @@ CREATE OPERATOR CLASS halfvec_l1_ops
 	FUNCTION 1 l1_distance(halfvec, halfvec),
 	FUNCTION 3 hnsw_halfvec_support(internal);

+-- intvec type
+
+CREATE TYPE intvec;
+
+CREATE FUNCTION intvec_in(cstring, oid, integer) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_out(intvec) RETURNS cstring
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_typmod_in(cstring[]) RETURNS integer
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_recv(internal, oid, integer) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_send(intvec) RETURNS bytea
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE TYPE intvec (
+	INPUT     = intvec_in,
+	OUTPUT    = intvec_out,
+	TYPMOD_IN = intvec_typmod_in,
+	RECEIVE   = intvec_recv,
+	SEND      = intvec_send,
+	STORAGE   = external
+);
+
+-- intvec functions
+
+CREATE FUNCTION l2_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l2_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION inner_product(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_inner_product' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION cosine_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_cosine_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION l1_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l1_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION vector_dims(intvec) RETURNS integer
+	AS 'MODULE_PATHNAME', 'intvec_vector_dims' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION l2_norm(intvec) RETURNS float8
+	AS 'MODULE_PATHNAME', 'intvec_l2_norm' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+-- intvec private functions
+
+CREATE FUNCTION intvec_lt(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_le(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_eq(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_ne(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_ge(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_gt(intvec, intvec) RETURNS bool
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_cmp(intvec, intvec) RETURNS int4
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_l2_squared_distance(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_negative_inner_product(intvec, intvec) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+-- intvec cast functions
+
+CREATE FUNCTION intvec(intvec, integer, boolean) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION array_to_intvec(integer[], integer, boolean) RETURNS intvec
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION intvec_to_integer(intvec, integer, boolean) RETURNS integer[]
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+-- intvec casts
+
+CREATE CAST (intvec AS intvec)
+	WITH FUNCTION intvec(intvec, integer, boolean) AS IMPLICIT;
+
+CREATE CAST (intvec AS integer[])
+	WITH FUNCTION intvec_to_integer(intvec, integer, boolean) AS ASSIGNMENT;
+
+CREATE CAST (integer[] AS intvec)
+	WITH FUNCTION array_to_intvec(integer[], integer, boolean) AS ASSIGNMENT;
+
+-- intvec operators
+
+CREATE OPERATOR <-> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = l2_distance,
+	COMMUTATOR = '<->'
+);
+
+CREATE OPERATOR <#> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_negative_inner_product,
+	COMMUTATOR = '<#>'
+);
+
+CREATE OPERATOR <=> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = cosine_distance,
+	COMMUTATOR = '<=>'
+);
+
+CREATE OPERATOR <+> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = l1_distance,
+	COMMUTATOR = '<+>'
+);
+
+CREATE OPERATOR < (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_lt,
+	COMMUTATOR = > , NEGATOR = >= ,
+	RESTRICT = scalarltsel, JOIN = scalarltjoinsel
+);
+
+CREATE OPERATOR <= (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_le,
+	COMMUTATOR = >= , NEGATOR = > ,
+	RESTRICT = scalarlesel, JOIN = scalarlejoinsel
+);
+
+CREATE OPERATOR = (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_eq,
+	COMMUTATOR = = , NEGATOR = <> ,
+	RESTRICT = eqsel, JOIN = eqjoinsel
+);
+
+CREATE OPERATOR <> (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_ne,
+	COMMUTATOR = <> , NEGATOR = = ,
+	RESTRICT = eqsel, JOIN = eqjoinsel
+);
+
+CREATE OPERATOR >= (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_ge,
+	COMMUTATOR = <= , NEGATOR = < ,
+	RESTRICT = scalargesel, JOIN = scalargejoinsel
+);
+
+CREATE OPERATOR > (
+	LEFTARG = intvec, RIGHTARG = intvec, PROCEDURE = intvec_gt,
+	COMMUTATOR = < , NEGATOR = <= ,
+	RESTRICT = scalargtsel, JOIN = scalargtjoinsel
+);
+
+-- intvec opclasses
+
+CREATE OPERATOR CLASS intvec_ops
+	DEFAULT FOR TYPE intvec USING btree AS
+	OPERATOR 1 < ,
+	OPERATOR 2 <= ,
+	OPERATOR 3 = ,
+	OPERATOR 4 >= ,
+	OPERATOR 5 > ,
+	FUNCTION 1 intvec_cmp(intvec, intvec);
+
+CREATE OPERATOR CLASS intvec_l2_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <-> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 intvec_l2_squared_distance(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_ip_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <#> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 intvec_negative_inner_product(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_cosine_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <=> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 cosine_distance(intvec, intvec),
+	FUNCTION 2 l2_norm(intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
+CREATE OPERATOR CLASS intvec_l1_ops
+	FOR TYPE intvec USING hnsw AS
+	OPERATOR 1 <+> (intvec, intvec) FOR ORDER BY float_ops,
+	FUNCTION 1 l1_distance(intvec, intvec),
+	FUNCTION 3 hnsw_intvec_support(internal);
+
 -- bit functions

 CREATE FUNCTION hamming_distance(bit, bit) RETURNS float8
--- a/src/bitutils.c
+++ b/src/bitutils.c
@@ -31,12 +31,10 @@
 #define BIT_TARGET_CLONES
 #endif

-/* Use built-ins when possible for Postgres < 19 for inlining */
-#if PG_VERSION_NUM >= 190000
-#define popcount64(x) pg_popcount64(x)
-#elif defined(HAVE__BUILTIN_POPCOUNT) && (defined(HAVE_LONG_INT_64) || SIZEOF_LONG == 8)
+/* Use built-ins when possible for inlining */
+#if defined(HAVE__BUILTIN_POPCOUNT) && defined(HAVE_LONG_INT_64)
 #define popcount64(x) __builtin_popcountl(x)
-#elif defined(HAVE__BUILTIN_POPCOUNT) && (defined(HAVE_LONG_LONG_INT_64) || SIZEOF_LONG_LONG == 8)
+#elif defined(HAVE__BUILTIN_POPCOUNT) && defined(HAVE_LONG_LONG_INT_64)
 #define popcount64(x) __builtin_popcountll(x)
 #elif !defined(_MSC_VER)
 /* Fails to resolve with MSVC */
@@ -171,7 +169,7 @@ BitJaccardDistanceAvx512Popcount(uint32 bytes, unsigned char *ax, unsigned char
 #endif

 TARGET_XSAVE static bool
-SupportsAvx512Popcount(void)
+SupportsAvx512Popcount()
 {
 	unsigned int exx[4] = {0, 0, 0, 0};

--- a/src/bitvec.c
+++ b/src/bitvec.c
@@ -2,7 +2,6 @@

 #include "bitutils.h"
 #include "bitvec.h"
-#include "fmgr.h"
 #include "utils/varbit.h"
 #include "vector.h"

--- a/src/halfutils.c
+++ b/src/halfutils.c
@@ -1,7 +1,5 @@
 #include "postgres.h"

-#include <math.h>
-
 #include "halfutils.h"
 #include "halfvec.h"

--- a/src/halfvec.c
+++ b/src/halfvec.c
@@ -13,20 +13,12 @@
 #include "port.h"				/* for strtof() */
 #include "sparsevec.h"
 #include "utils/array.h"
+#include "utils/builtins.h"
 #include "utils/float.h"
-#include "utils/fmgrprotos.h"
 #include "utils/lsyscache.h"
-#include "utils/varbit.h"
+#include "utils/numeric.h"
 #include "vector.h"

-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
-
-#if PG_VERSION_NUM >= 170000
-#include "parser/scansup.h"
-#endif
-
 #define STATE_DIMS(x) (ARR_DIMS(x)[0] - 1)
 #define CreateStateDatums(dim) palloc(sizeof(Datum) * (dim + 1))

@@ -137,9 +129,9 @@ InitHalfVector(int dim)
 	return result;
 }

-#if PG_VERSION_NUM >= 170000
-#define halfvec_isspace(ch) scanner_isspace(ch)
-#else
+/*
+ * Check for whitespace, since array_isspace() is static
+ */
 static inline bool
 halfvec_isspace(char ch)
 {
@@ -152,7 +144,6 @@ halfvec_isspace(char ch)
 		return true;
 	return false;
 }
-#endif

 /*
 * Check state array
@@ -907,21 +898,8 @@ halfvec_binary_quantize(PG_FUNCTION_ARGS)
 	half	   *ax = a->x;
 	VarBit	   *result = InitBitVector(a->dim);
 	unsigned char *rx = VARBITS(result);
-	int			i = 0;
-	int			count = (a->dim / 8) * 8;

-	/* Auto-vectorized on aarch64 */
-	for (; i < count; i += 8)
-	{
-		unsigned char result_byte = 0;
-
-		for (int j = 0; j < 8; j++)
-			result_byte |= (HalfToFloat4(ax[i + j]) > 0) << (7 - j);
-
-		rx[i / 8] = result_byte;
-	}
-
-	for (; i < a->dim; i++)
+	for (int i = 0; i < a->dim; i++)
 		rx[i / 8] |= (HalfToFloat4(ax[i]) > 0) << (7 - (i % 8));

 	PG_RETURN_VARBIT_P(result);
--- a/src/hnsw.c
+++ b/src/hnsw.c
@@ -1,41 +1,33 @@
 #include "postgres.h"

 #include <float.h>
-#include <limits.h>
 #include <math.h>

 #include "access/amapi.h"
-#include "access/genam.h"
 #include "access/reloptions.h"
 #include "commands/progress.h"
 #include "commands/vacuum.h"
-#include "fmgr.h"
 #include "hnsw.h"
 #include "miscadmin.h"
-#include "nodes/pg_list.h"
-#include "storage/lwlock.h"
 #include "utils/float.h"
 #include "utils/guc.h"
-#include "utils/relcache.h"
 #include "utils/selfuncs.h"
 #include "utils/spccache.h"
-#include "vector.h"

 #if PG_VERSION_NUM < 150000
 #define MarkGUCPrefixReserved(x) EmitWarningsOnPlaceholders(x)
 #endif

-static const struct config_enum_entry hnsw_iterative_scan_options[] = {
-	{"off", HNSW_ITERATIVE_SCAN_OFF, false},
-	{"relaxed_order", HNSW_ITERATIVE_SCAN_RELAXED, false},
-	{"strict_order", HNSW_ITERATIVE_SCAN_STRICT, false},
+static const struct config_enum_entry hnsw_iterative_search_options[] = {
+	{"off", HNSW_ITERATIVE_SEARCH_OFF, false},
+	{"relaxed_order", HNSW_ITERATIVE_SEARCH_RELAXED, false},
+	{"strict_order", HNSW_ITERATIVE_SEARCH_STRICT, false},
 	{NULL, 0, false}
 };

 int			hnsw_ef_search;
-int			hnsw_iterative_scan;
-int			hnsw_max_scan_tuples;
-double		hnsw_scan_mem_multiplier;
+int			hnsw_max_search_tuples;
+int			hnsw_iterative_search;
 int			hnsw_lock_tranche_id;
 static relopt_kind hnsw_relopt_kind;

@@ -59,20 +51,12 @@ HnswInitLockTranche(void)
 								  sizeof(int) * 1,
 								  &found);
 	if (!found)
-	{
-#if PG_VERSION_NUM >= 190000
-		tranche_ids[0] = LWLockNewTrancheId("HnswBuild");
-#else
 		tranche_ids[0] = LWLockNewTrancheId();
-#endif
-	}
 	hnsw_lock_tranche_id = tranche_ids[0];
 	LWLockRelease(AddinShmemInitLock);

-#if PG_VERSION_NUM < 190000
 	/* Per-backend registration of the tranche ID */
 	LWLockRegisterTranche(hnsw_lock_tranche_id, "HnswBuild");
-#endif
 }

 /*
@@ -94,19 +78,14 @@ HnswInit(void)
 							"Valid range is 1..1000.", &hnsw_ef_search,
 							HNSW_DEFAULT_EF_SEARCH, HNSW_MIN_EF_SEARCH, HNSW_MAX_EF_SEARCH, PGC_USERSET, 0, NULL, NULL, NULL);

-	DefineCustomEnumVariable("hnsw.iterative_scan", "Sets the mode for iterative scans",
-							 NULL, &hnsw_iterative_scan,
-							 HNSW_ITERATIVE_SCAN_OFF, hnsw_iterative_scan_options, PGC_USERSET, 0, NULL, NULL, NULL);
+	DefineCustomEnumVariable("hnsw.iterative_search", "Sets the iterative search mode",
+							 NULL, &hnsw_iterative_search,
+							 HNSW_ITERATIVE_SEARCH_OFF, hnsw_iterative_search_options, PGC_USERSET, 0, NULL, NULL, NULL);

-	/* This is approximate and does not affect the initial scan */
-	DefineCustomIntVariable("hnsw.max_scan_tuples", "Sets the max number of tuples to visit for iterative scans",
-							NULL, &hnsw_max_scan_tuples,
-							20000, 1, INT_MAX, PGC_USERSET, 0, NULL, NULL, NULL);
-
-	/* Same range as hash_mem_multiplier */
-	DefineCustomRealVariable("hnsw.scan_mem_multiplier", "Sets the multiple of work_mem to use for iterative scans",
-							 NULL, &hnsw_scan_mem_multiplier,
-							 1, 1, 1000, PGC_USERSET, 0, NULL, NULL, NULL);
+	/* This is approximate and does not apply to the initial scan */
+	DefineCustomIntVariable("hnsw.max_search_tuples", "Sets the max number of candidates to visit for iterative search",
+							"-1 means no limit", &hnsw_max_search_tuples,
+							-1, -1, INT_MAX, PGC_USERSET, 0, NULL, NULL, NULL);

 	MarkGUCPrefixReserved("hnsw");
 }
@@ -145,17 +124,13 @@ hnswcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	Relation	index;

 	/* Never use index without order */
-	if (path->indexorderbys == NIL)
+	if (path->indexorderbys == NULL)
 	{
 		*indexStartupCost = get_float8_infinity();
 		*indexTotalCost = get_float8_infinity();
 		*indexSelectivity = 0;
 		*indexCorrelation = 0;
 		*indexPages = 0;
-#if PG_VERSION_NUM >= 180000
-		/* See "On disable_cost" thread on pgsql-hackers */
-		path->path.disabled_nodes = 2;
-#endif
 		return;
 	}

@@ -267,64 +242,6 @@ FUNCTION_PREFIX PG_FUNCTION_INFO_V1(hnswhandler);
 Datum
 hnswhandler(PG_FUNCTION_ARGS)
 {
-#if PG_VERSION_NUM >= 190000
-	static const IndexAmRoutine amroutine = {
-		.type = T_IndexAmRoutine,
-		.amstrategies = 0,
-		.amsupport = 3,
-		.amoptsprocnum = 0,
-		.amcanorder = false,
-		.amcanorderbyop = true,
-		.amcanhash = false,
-		.amconsistentequality = false,
-		.amconsistentordering = false,
-		.amcanbackward = false,
-		.amcanunique = false,
-		.amcanmulticol = false,
-		.amoptionalkey = true,
-		.amsearcharray = false,
-		.amsearchnulls = false,
-		.amstorage = false,
-		.amclusterable = false,
-		.ampredlocks = false,
-		.amcanparallel = false,
-		.amcanbuildparallel = true,
-		.amcaninclude = false,
-		.amusemaintenanceworkmem = false,
-		.amsummarizing = false,
-		.amparallelvacuumoptions = VACUUM_OPTION_PARALLEL_BULKDEL,
-		.amkeytype = InvalidOid,
-
-		.ambuild = hnswbuild,
-		.ambuildempty = hnswbuildempty,
-		.aminsert = hnswinsert,
-		.aminsertcleanup = NULL,
-		.ambulkdelete = hnswbulkdelete,
-		.amvacuumcleanup = hnswvacuumcleanup,
-		.amcanreturn = NULL,
-		.amcostestimate = hnswcostestimate,
-		.amgettreeheight = NULL,
-		.amoptions = hnswoptions,
-		.amproperty = NULL,
-		.ambuildphasename = hnswbuildphasename,
-		.amvalidate = hnswvalidate,
-		.amadjustmembers = NULL,
-		.ambeginscan = hnswbeginscan,
-		.amrescan = hnswrescan,
-		.amgettuple = hnswgettuple,
-		.amgetbitmap = NULL,
-		.amendscan = hnswendscan,
-		.ammarkpos = NULL,
-		.amrestrpos = NULL,
-		.amestimateparallelscan = NULL,
-		.aminitparallelscan = NULL,
-		.amparallelrescan = NULL,
-		.amtranslatestrategy = NULL,
-		.amtranslatecmptype = NULL,
-	};
-
-	PG_RETURN_POINTER(&amroutine);
-#else
 	IndexAmRoutine *amroutine = makeNode(IndexAmRoutine);

 	amroutine->amstrategies = 0;
@@ -332,11 +249,6 @@ hnswhandler(PG_FUNCTION_ARGS)
 	amroutine->amoptsprocnum = 0;
 	amroutine->amcanorder = false;
 	amroutine->amcanorderbyop = true;
-#if PG_VERSION_NUM >= 180000
-	amroutine->amcanhash = false;
-	amroutine->amconsistentequality = false;
-	amroutine->amconsistentordering = false;
-#endif
 	amroutine->amcanbackward = false;	/* can change direction mid-scan */
 	amroutine->amcanunique = false;
 	amroutine->amcanmulticol = false;
@@ -369,9 +281,6 @@ hnswhandler(PG_FUNCTION_ARGS)
 	amroutine->amvacuumcleanup = hnswvacuumcleanup;
 	amroutine->amcanreturn = NULL;
 	amroutine->amcostestimate = hnswcostestimate;
-#if PG_VERSION_NUM >= 180000
-	amroutine->amgettreeheight = NULL;
-#endif
 	amroutine->amoptions = hnswoptions;
 	amroutine->amproperty = NULL;	/* TODO AMPROP_DISTANCE_ORDERABLE */
 	amroutine->ambuildphasename = hnswbuildphasename;
@@ -392,11 +301,5 @@ hnswhandler(PG_FUNCTION_ARGS)
 	amroutine->aminitparallelscan = NULL;
 	amroutine->amparallelrescan = NULL;

-#if PG_VERSION_NUM >= 180000
-	amroutine->amtranslatestrategy = NULL;
-	amroutine->amtranslatecmptype = NULL;
-#endif
-
 	PG_RETURN_POINTER(amroutine);
-#endif
 }
--- a/src/hnsw.h
+++ b/src/hnsw.h
@@ -3,29 +3,15 @@

 #include "postgres.h"

-#include <math.h>
-
 #include "access/genam.h"
 #include "access/parallel.h"
 #include "lib/pairingheap.h"
 #include "nodes/execnodes.h"
 #include "port.h"				/* for random() */
-#include "storage/bufpage.h"
-#include "storage/condition_variable.h"
-#include "storage/lwlock.h"
-#include "storage/s_lock.h"
 #include "utils/relptr.h"
 #include "utils/sampling.h"
 #include "vector.h"

-#ifdef HNSW_BENCH
-#include "portability/instr_time.h"
-#endif
-
-#if PG_VERSION_NUM >= 190000
-typedef Pointer Item;
-#endif
-
 #define HNSW_MAX_DIM 2000
 #define HNSW_MAX_NNZ 1000

@@ -82,21 +68,6 @@ typedef Pointer Item;
 #define HnswPageGetOpaque(page)	((HnswPageOpaque) PageGetSpecialPointer(page))
 #define HnswPageGetMeta(page)	((HnswMetaPageData *) PageGetContents(page))

-#ifdef HNSW_BENCH
-#define HnswBench(name, code) \
-	do { \
-		instr_time	start; \
-		instr_time	duration; \
-		INSTR_TIME_SET_CURRENT(start); \
-		(code); \
-		INSTR_TIME_SET_CURRENT(duration); \
-		INSTR_TIME_SUBTRACT(duration, start); \
-		elog(INFO, "%s: %.3f ms", name, INSTR_TIME_GET_MILLISEC(duration)); \
-	} while (0)
-#else
-#define HnswBench(name, code) (code)
-#endif
-
 #if PG_VERSION_NUM >= 150000
 #define RandomDouble() pg_prng_double(&pg_global_prng_state)
 #define SeedRandom(seed) pg_prng_seed(&pg_global_prng_state, seed)
@@ -138,24 +109,23 @@ typedef Pointer Item;

 /* Variables */
 extern int	hnsw_ef_search;
-extern int	hnsw_iterative_scan;
-extern int	hnsw_max_scan_tuples;
-extern double hnsw_scan_mem_multiplier;
+extern int	hnsw_iterative_search;
+extern int	hnsw_max_search_tuples;
 extern int	hnsw_lock_tranche_id;

-typedef enum HnswIterativeScanMode
+typedef enum HnswIterativeSearchMode
 {
-	HNSW_ITERATIVE_SCAN_OFF,
-	HNSW_ITERATIVE_SCAN_RELAXED,
-	HNSW_ITERATIVE_SCAN_STRICT
-}			HnswIterativeScanMode;
+	HNSW_ITERATIVE_SEARCH_OFF,
+	HNSW_ITERATIVE_SEARCH_RELAXED,
+	HNSW_ITERATIVE_SEARCH_STRICT
+}			HnswIterativeSearchMode;

 typedef struct HnswElementData HnswElementData;
 typedef struct HnswNeighborArray HnswNeighborArray;

 #define HnswPtrDeclare(type, relptrtype, ptrtype) \
 	relptr_declare(type, relptrtype); \
-	typedef union { type *ptr; relptrtype relptr; } ptrtype
+	typedef union { type *ptr; relptrtype relptr; } ptrtype;

 /* Pointers that can be absolute or relative */
 /* Use char for DatumPtr so works with Pointer */
@@ -402,7 +372,6 @@ typedef struct HnswScanOpaqueData
 	int			m;
 	int64		tuples;
 	double		previousDistance;
-	Size		maxMemory;
 	MemoryContext tmpCtx;

 	/* Support functions */
@@ -427,11 +396,10 @@ typedef struct HnswVacuumState
 	HnswSupport support;

 	/* Variables */
-	struct tidhash_hash *deleting;
+	struct tidhash_hash *deleted;
 	BufferAccessStrategy bas;
 	HnswNeighborTuple ntup;
 	HnswElementData highestPoint;
-	HnswElementData fallbackPoint;

 	/* Memory */
 	MemoryContext tmpCtx;
@@ -454,7 +422,7 @@ void	   *HnswAlloc(HnswAllocator * allocator, Size size);
 HnswElement HnswInitElement(char *base, ItemPointer tid, int m, double ml, int maxLevel, HnswAllocator * alloc);
 HnswElement HnswInitElementFromBlock(BlockNumber blkno, OffsetNumber offno);
 void		HnswFindElementNeighbors(char *base, HnswElement element, HnswElement entryPoint, Relation index, HnswSupport * support, int m, int efConstruction, bool existing);
-HnswSearchCandidate *HnswEntryCandidate(char *base, HnswElement entryPoint, HnswQuery * q, Relation index, HnswSupport * support, bool loadVec);
+HnswSearchCandidate *HnswEntryCandidate(char *base, HnswElement em, HnswQuery * q, Relation rel, HnswSupport * support, bool loadVec);
 void		HnswUpdateMetaPage(Relation index, int updateEntry, HnswElement entryPoint, BlockNumber insertPage, ForkNumber forkNum, bool building);
 void		HnswSetNeighborTuple(char *base, HnswNeighborTuple ntup, HnswElement e, int m);
 void		HnswAddHeapTid(HnswElement element, ItemPointer heaptid);
--- a/src/hnswbuild.c
+++ b/src/hnswbuild.c
@@ -36,14 +36,11 @@
 */
 #include "postgres.h"

-#include <limits.h>
+#include <math.h>

-#include "access/genam.h"
 #include "access/parallel.h"
-#include "access/relscan.h"
 #include "access/table.h"
 #include "access/tableam.h"
-#include "access/tupdesc.h"
 #include "access/xact.h"
 #include "access/xloginsert.h"
 #include "catalog/index.h"
@@ -51,19 +48,11 @@
 #include "commands/progress.h"
 #include "hnsw.h"
 #include "miscadmin.h"
-#include "nodes/execnodes.h"
 #include "optimizer/optimizer.h"
 #include "storage/bufmgr.h"
-#include "storage/condition_variable.h"
 #include "tcop/tcopprot.h"
 #include "utils/datum.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"
-#include "utils/snapmgr.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 #if PG_VERSION_NUM >= 140000
 #include "utils/backend_progress.h"
@@ -80,8 +69,6 @@
 #define PARALLEL_KEY_HNSW_AREA			UINT64CONST(0xA000000000000002)
 #define PARALLEL_KEY_QUERY_TEXT			UINT64CONST(0xA000000000000003)

-#define HNSW_MAX_GRAPH_MEMORY (SIZE_MAX / 2)
-
 /*
 * Create the metapage
 */
@@ -411,7 +398,7 @@ UpdateNeighborsInMemory(char *base, HnswSupport * support, HnswElement e, int m)
 * Update graph in memory
 */
 static void
-UpdateGraphInMemory(HnswSupport * support, HnswElement element, int m, HnswElement entryPoint, HnswBuildState * buildstate)
+UpdateGraphInMemory(HnswSupport * support, HnswElement element, int m, int efConstruction, HnswElement entryPoint, HnswBuildState * buildstate)
 {
 	HnswGraph  *graph = buildstate->graph;
 	char	   *base = buildstate->hnswarea;
@@ -473,7 +460,7 @@ InsertTupleInMemory(HnswBuildState * buildstate, HnswElement element)
 	HnswFindElementNeighbors(base, element, entryPoint, NULL, support, m, efConstruction, false);

 	/* Update graph in memory */
-	UpdateGraphInMemory(support, element, m, entryPoint, buildstate);
+	UpdateGraphInMemory(support, element, m, efConstruction, entryPoint, buildstate);

 	/* Release entry lock */
 	LWLockRelease(entryLock);
@@ -494,7 +481,6 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heaptid, Hn
 	LWLock	   *flushLock = &graph->flushLock;
 	char	   *base = buildstate->hnswarea;
 	Datum		value;
-	Size		memoryMargin;

 	/* Form index value */
 	if (!HnswFormIndexValue(&value, values, isnull, buildstate->typeInfo, support))
@@ -503,9 +489,6 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heaptid, Hn
 	/* Get datum size */
 	valueSize = VARSIZE_ANY(DatumGetPointer(value));

-	/* In a parallel build, add a margin so allocations never fail */
-	memoryMargin = base == NULL ? 0 : 1024 * 1024;
-
 	/* Ensure graph not flushed when inserting */
 	LWLockAcquire(flushLock, LW_SHARED);

@@ -527,7 +510,7 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heaptid, Hn
 	 * Check that we have enough memory available for the new element now that
 	 * we have the allocator lock, and flush pages if needed.
 	 */
-	if (graph->memoryUsed + memoryMargin >= graph->memoryTotal)
+	if (graph->memoryUsed >= graph->memoryTotal)
 	{
 		LWLockRelease(&graph->allocatorLock);

@@ -562,7 +545,7 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heaptid, Hn

 	/* Copy the datum */
 	memcpy(valuePtr, DatumGetPointer(value), valueSize);
-	HnswPtrStore(base, element->value, (char *) valuePtr);
+	HnswPtrStore(base, element->value, valuePtr);

 	/* Create a lock for the element */
 	LWLockInitialize(&element->lock, hnsw_lock_tranche_id);
@@ -620,7 +603,7 @@ InitGraph(HnswGraph * graph, char *base, Size memoryTotal)
 	HnswPtrStore(base, graph->head, (HnswElement) NULL);
 	HnswPtrStore(base, graph->entryPoint, (HnswElement) NULL);
 	graph->memoryUsed = 0;
-	graph->memoryTotal = Min(memoryTotal, HNSW_MAX_GRAPH_MEMORY);
+	graph->memoryTotal = memoryTotal;
 	graph->flushed = false;
 	graph->indtuples = 0;
 	SpinLockInit(&graph->lock);
@@ -661,17 +644,9 @@ static void *
 HnswSharedMemoryAlloc(Size size, void *state)
 {
 	HnswBuildState *buildstate = (HnswBuildState *) state;
-	Size		alignedSize = MAXALIGN(size);
-	void	   *chunk;
+	void	   *chunk = buildstate->hnswarea + buildstate->graph->memoryUsed;

-	if (alignedSize > 1024 * 1024)
-		elog(ERROR, "hnsw allocation too large");
-
-	if (buildstate->graph->memoryUsed + alignedSize > buildstate->graph->memoryTotal)
-		elog(ERROR, "hnsw allocator out of memory");
-
-	chunk = buildstate->hnswarea + buildstate->graph->memoryUsed;
-	buildstate->graph->memoryUsed += alignedSize;
+	buildstate->graph->memoryUsed += MAXALIGN(size);
 	return chunk;
 }

@@ -719,7 +694,7 @@ InitBuildState(HnswBuildState * buildstate, Relation heap, Relation index, Index
 	/* Get support functions */
 	HnswInitSupport(&buildstate->support, index);

-	InitGraph(&buildstate->graphData, NULL, maintenance_work_mem * (Size) 1024);
+	InitGraph(&buildstate->graphData, NULL, (Size) maintenance_work_mem * 1024L);
 	buildstate->graph = &buildstate->graphData;
 	buildstate->ml = HnswGetMl(buildstate->m);
 	buildstate->maxLevel = HnswGetMaxLevel(buildstate->m);
@@ -803,11 +778,7 @@ HnswParallelScanAndInsert(Relation heapRel, Relation indexRel, HnswShared * hnsw
 	buildstate.hnswarea = hnswarea;
 	InitAllocator(&buildstate.allocator, &HnswSharedMemoryAlloc, &buildstate);
 	scan = table_beginscan_parallel(heapRel,
-									ParallelTableScanFromHnswShared(hnswshared)
-#if PG_VERSION_NUM >= 190000
-									,SO_NONE
-#endif
-		);
+									ParallelTableScanFromHnswShared(hnswshared));
 	reltuples = table_index_build_scan(heapRel, indexRel, indexInfo,
 									   true, progress, BuildCallback,
 									   (void *) &buildstate, scan);
@@ -956,13 +927,11 @@ HnswBeginParallel(HnswBuildState * buildstate, bool isconcurrent, int request)
 	/* Leave space for other objects in shared memory */
 	/* Docker has a default limit of 64 MB for shm_size */
 	/* which happens to be the default value of maintenance_work_mem */
-	esthnswarea = maintenance_work_mem * (Size) 1024;
+	esthnswarea = maintenance_work_mem * 1024L;
 	estother = 3 * 1024 * 1024;
 	if (esthnswarea > estother)
 		esthnswarea -= estother;

-	esthnswarea = Min(esthnswarea, HNSW_MAX_GRAPH_MEMORY);
-
 	shm_toc_estimate_chunk(&pcxt->estimator, esthnswarea);
 	shm_toc_estimate_keys(&pcxt->estimator, 2);

@@ -1005,7 +974,8 @@ HnswBeginParallel(HnswBuildState * buildstate, bool isconcurrent, int request)
 								  snapshot);

 	hnswarea = (char *) shm_toc_allocate(pcxt->toc, esthnswarea);
-	InitGraph(&hnswshared->graphData, hnswarea, esthnswarea);
+	/* Report less than allocated so never fails */
+	InitGraph(&hnswshared->graphData, hnswarea, esthnswarea - 1024 * 1024);

 	/*
 	 * Avoid base address for relptr for Postgres < 14.5
@@ -1084,7 +1054,7 @@ ComputeParallelWorkers(Relation heap, Relation index)
 * Build graph
 */
 static void
-BuildGraph(HnswBuildState * buildstate)
+BuildGraph(HnswBuildState * buildstate, ForkNumber forkNum)
 {
 	int			parallel_workers = 0;

@@ -1132,7 +1102,7 @@ BuildIndex(Relation heap, Relation index, IndexInfo *indexInfo,

 	InitBuildState(buildstate, heap, index, indexInfo, forkNum);

-	BuildGraph(buildstate);
+	BuildGraph(buildstate, forkNum);

 	if (RelationNeedsWAL(index) || forkNum == INIT_FORKNUM)
 		log_newpage_range(index, forkNum, 0, RelationGetNumberOfBlocksInFork(index, forkNum), true);
--- a/src/hnswinsert.c
+++ b/src/hnswinsert.c
@@ -1,19 +1,13 @@
 #include "postgres.h"

-#include "access/genam.h"
+#include <math.h>
+
 #include "access/generic_xlog.h"
 #include "hnsw.h"
-#include "nodes/execnodes.h"
 #include "storage/bufmgr.h"
 #include "storage/lmgr.h"
-#include "storage/lwlock.h"
 #include "utils/datum.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 /*
 * Get the insert page
@@ -666,7 +660,7 @@ FindDuplicateOnDisk(Relation index, HnswElement element, bool building)
 * Update graph on disk
 */
 static void
-UpdateGraphOnDisk(Relation index, HnswSupport * support, HnswElement element, int m, HnswElement entryPoint, bool building)
+UpdateGraphOnDisk(Relation index, HnswSupport * support, HnswElement element, int m, int efConstruction, HnswElement entryPoint, bool building)
 {
 	BlockNumber newInsertPage = InvalidBlockNumber;

@@ -714,7 +708,7 @@ HnswInsertTupleOnDisk(Relation index, HnswSupport * support, Datum value, ItemPo

 	/* Create an element */
 	element = HnswInitElement(base, heaptid, m, HnswGetMl(m), HnswGetMaxLevel(m), NULL);
-	HnswPtrStore(base, element->value, (char *) DatumGetPointer(value));
+	HnswPtrStore(base, element->value, DatumGetPointer(value));

 	/* Prevent concurrent inserts when likely updating entry point */
 	if (entryPoint == NULL || element->level > entryPoint->level)
@@ -734,7 +728,7 @@ HnswInsertTupleOnDisk(Relation index, HnswSupport * support, Datum value, ItemPo
 	HnswFindElementNeighbors(base, element, entryPoint, index, support, m, efConstruction, false);

 	/* Update graph on disk */
-	UpdateGraphOnDisk(index, support, element, m, entryPoint, building);
+	UpdateGraphOnDisk(index, support, element, m, efConstruction, entryPoint, building);

 	/* Release lock */
 	UnlockPage(index, HNSW_UPDATE_LOCK, lockmode);
--- a/src/hnswscan.c
+++ b/src/hnswscan.c
@@ -1,23 +1,12 @@
 #include "postgres.h"

-#include <limits.h>
-
-#include "access/genam.h"
 #include "access/relscan.h"
 #include "hnsw.h"
-#include "lib/pairingheap.h"
-#include "miscadmin.h"
-#include "nodes/pg_list.h"
 #include "pgstat.h"
+#include "storage/bufmgr.h"
 #include "storage/lmgr.h"
 #include "utils/float.h"
 #include "utils/memutils.h"
-#include "utils/relcache.h"
-#include "utils/snapmgr.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 /*
 * Algorithm 5 from paper
@@ -52,7 +41,7 @@ GetScanItems(IndexScanDesc scan, Datum value)
 		ep = w;
 	}

-	return HnswSearchLayer(base, q, ep, hnsw_ef_search, 0, index, support, m, false, NULL, &so->v, hnsw_iterative_scan != HNSW_ITERATIVE_SCAN_OFF ? &so->discarded : NULL, true, &so->tuples);
+	return HnswSearchLayer(base, q, ep, hnsw_ef_search, 0, index, support, m, false, NULL, &so->v, hnsw_iterative_search != HNSW_ITERATIVE_SEARCH_OFF ? &so->discarded : NULL, true, &so->tuples);
 }

 /*
@@ -132,15 +121,14 @@ hnswbeginscan(Relation index, int nkeys, int norderbys)
 {
 	IndexScanDesc scan;
 	HnswScanOpaque so;
-	double		maxMemory;

 	scan = RelationGetIndexScan(index, nkeys, norderbys);

 	so = (HnswScanOpaque) palloc(sizeof(HnswScanOpaqueData));
 	so->typeInfo = HnswGetTypeInfo(index);
-
-	/* Set support functions */
-	HnswInitSupport(&so->support, index);
+	so->first = true;
+	so->v.tids = NULL;
+	so->discarded = NULL;

 	/*
 	 * Use a lower max allocation size than default to allow scanning more
@@ -148,12 +136,10 @@ hnswbeginscan(Relation index, int nkeys, int norderbys)
 	 */
 	so->tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
 									   "Hnsw scan temporary context",
-									   0, 8 * 1024, 256 * 1024);
+									   0, 8 * 1024, 512 * 1024);

-	/* Calculate max memory */
-	/* Add 256 extra bytes to fill last block when close */
-	maxMemory = (double) work_mem * hnsw_scan_mem_multiplier * 1024.0 + 256;
-	so->maxMemory = Min(maxMemory, (double) (SIZE_MAX / 2));
+	/* Set support functions */
+	HnswInitSupport(&so->support, index);

 	scan->opaque = so;

@@ -168,10 +154,13 @@ hnswrescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int no
 {
 	HnswScanOpaque so = (HnswScanOpaque) scan->opaque;

+	if (so->v.tids != NULL)
+		tidhash_reset(so->v.tids);
+
+	if (so->discarded != NULL)
+		pairingheap_reset(so->discarded);
+
 	so->first = true;
-	/* v and discarded are allocated in tmpCtx */
-	so->v.tids = NULL;
-	so->discarded = NULL;
 	so->tuples = 0;
 	so->previousDistance = -get_float8_infinity();
 	MemoryContextReset(so->tmpCtx);
@@ -204,10 +193,6 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)

 		/* Count index scan for stats */
 		pgstat_count_index_scan(scan->indexRelation);
-#if PG_VERSION_NUM >= 180000
-		if (scan->instrument)
-			scan->instrument->nsearches++;
-#endif

 		/* Safety check */
 		if (scan->orderByData == NULL)
@@ -248,15 +233,15 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)

 		if (list_length(so->w) == 0)
 		{
-			if (hnsw_iterative_scan == HNSW_ITERATIVE_SCAN_OFF)
+			if (hnsw_iterative_search == HNSW_ITERATIVE_SEARCH_OFF)
 				break;

 			/* Empty index */
 			if (so->discarded == NULL)
 				break;

-			/* Reached max number of tuples or memory limit */
-			if (so->tuples >= hnsw_max_scan_tuples || MemoryContextMemAllocated(so->tmpCtx, false) > so->maxMemory)
+			/* Reached max number of tuples */
+			if (hnsw_max_search_tuples != -1 && so->tuples >= hnsw_max_search_tuples)
 			{
 				if (pairingheap_is_empty(so->discarded))
 					break;
@@ -264,6 +249,21 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 				/* Return remaining tuples */
 				so->w = lappend(so->w, HnswGetSearchCandidate(w_node, pairingheap_remove_first(so->discarded)));
 			}
+			/* Prevent scans from consuming too much memory */
+			else if (MemoryContextMemAllocated(so->tmpCtx, false) > (Size) work_mem * 1024L)
+			{
+				if (pairingheap_is_empty(so->discarded))
+				{
+					ereport(DEBUG1,
+							(errmsg("hnsw index scan exceeded work_mem after " INT64_FORMAT " tuples", so->tuples),
+							 errhint("Increase work_mem to scan more tuples.")));
+
+					break;
+				}
+
+				/* Return remaining tuples */
+				so->w = lappend(so->w, HnswGetSearchCandidate(w_node, pairingheap_remove_first(so->discarded)));
+			}
 			else
 			{
 				/*
@@ -299,7 +299,7 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 			so->w = list_delete_last(so->w);

 			/* Mark memory as free for next iteration */
-			if (hnsw_iterative_scan != HNSW_ITERATIVE_SCAN_OFF)
+			if (hnsw_iterative_search != HNSW_ITERATIVE_SEARCH_OFF)
 			{
 				pfree(element);
 				pfree(sc);
@@ -310,7 +310,7 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)

 		heaptid = &element->heaptids[--element->heaptidsLength];

-		if (hnsw_iterative_scan == HNSW_ITERATIVE_SCAN_STRICT)
+		if (hnsw_iterative_search == HNSW_ITERATIVE_SEARCH_STRICT)
 		{
 			if (sc->distance < so->previousDistance)
 				continue;
--- a/src/hnswutils.c
+++ b/src/hnswutils.c
@@ -1,25 +1,20 @@
 #include "postgres.h"

+#include <float.h>
 #include <math.h>

-#include "access/genam.h"
 #include "access/generic_xlog.h"
+#include "catalog/pg_type.h"
+#include "catalog/pg_type_d.h"
 #include "common/hashfn.h"
 #include "fmgr.h"
 #include "hnsw.h"
 #include "lib/pairingheap.h"
-#include "nodes/pg_list.h"
-#include "port/atomics.h"
 #include "sparsevec.h"
 #include "storage/bufmgr.h"
 #include "utils/datum.h"
 #include "utils/memdebug.h"
 #include "utils/rel.h"
-#include "vector.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 #if PG_VERSION_NUM < 170000
 static inline uint64
@@ -163,6 +158,9 @@ HnswInitSupport(HnswSupport * support, Relation index)
 Datum
 HnswNormValue(const HnswTypeInfo * typeInfo, Oid collation, Datum value)
 {
+	if (!typeInfo->normalize)
+		return value;
+
 	return DirectFunctionCall1Coll(typeInfo->normalize, collation, value);
 }

@@ -262,7 +260,7 @@ HnswInitElement(char *base, ItemPointer heaptid, int m, double ml, int maxLevel,

 	HnswInitNeighbors(base, element, m, allocator);

-	HnswPtrStore(base, element->value, (char *) NULL);
+	HnswPtrStore(base, element->value, (Pointer) NULL);

 	return element;
 }
@@ -288,7 +286,7 @@ HnswInitElementFromBlock(BlockNumber blkno, OffsetNumber offno)
 	element->blkno = blkno;
 	element->offno = offno;
 	HnswPtrStore(base, element->neighbors, (HnswNeighborArrayPtr *) NULL);
-	HnswPtrStore(base, element->value, (char *) NULL);
+	HnswPtrStore(base, element->value, (Pointer) NULL);
 	return element;
 }

@@ -514,7 +512,7 @@ HnswLoadElementFromTuple(HnswElement element, HnswElementTuple etup, bool loadHe
 		char	   *base = NULL;
 		Datum		value = datumCopy(PointerGetDatum(&etup->data), false, -1);

-		HnswPtrStore(base, element->value, (char *) DatumGetPointer(value));
+		HnswPtrStore(base, element->value, DatumGetPointer(value));
 	}
 }

@@ -546,16 +544,20 @@ HnswLoadElementImpl(BlockNumber blkno, OffsetNumber offno, double *distance, Hns

 	Assert(HnswIsElementTuple(etup));

-	if (unlikely(etup->deleted))
-		elog(ERROR, "cannot load deleted element");
-
 	/* Calculate distance */
 	if (distance != NULL)
 	{
 		if (DatumGetPointer(q->value) == NULL)
 			*distance = 0;
 		else
+		{
 			*distance = HnswGetDistance(q->value, PointerGetDatum(&etup->data), support);
+
+			/* Needed for intvec cosine distance */
+			/* TODO Improve */
+			if (isnan(*distance))
+				*distance = DBL_MAX;
+		}
 	}

 	/* Load element */
@@ -866,7 +868,6 @@ HnswSearchLayer(char *base, HnswQuery * q, List *ep, int ef, int lc, Relation in
 		{
 			AddToVisited(base, v, sc->element, inMemory, &found);

-			/* OK to count elements instead of tuples */
 			if (tuples != NULL)
 				(*tuples)++;
 		}
@@ -899,7 +900,6 @@ HnswSearchLayer(char *base, HnswQuery * q, List *ep, int ef, int lc, Relation in
 		else
 			HnswLoadUnvisitedFromDisk(cElement, unvisited, &unvisitedLength, v, index, m, lm, lc);

-		/* OK to count elements instead of tuples */
 		if (tuples != NULL)
 			(*tuples) += unvisitedLength;

@@ -931,7 +931,7 @@ HnswSearchLayer(char *base, HnswQuery * q, List *ep, int ef, int lc, Relation in
 					continue;
 			}

-			if (!(eDistance < f->distance || alwaysAdd))
+			if (eElement == NULL || !(eDistance < f->distance || alwaysAdd))
 			{
 				if (discarded != NULL)
 				{
@@ -1402,7 +1402,20 @@ hnsw_halfvec_support(PG_FUNCTION_ARGS)
 	};

 	PG_RETURN_POINTER(&typeInfo);
-}
+};
+
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(hnsw_intvec_support);
+Datum
+hnsw_intvec_support(PG_FUNCTION_ARGS)
+{
+	static const HnswTypeInfo typeInfo = {
+		.maxDimensions = HNSW_MAX_DIM * 4,
+		.normalize = NULL,
+		.checkValue = NULL
+	};
+
+	PG_RETURN_POINTER(&typeInfo);
+};

 FUNCTION_PREFIX PG_FUNCTION_INFO_V1(hnsw_bit_support);
 Datum
@@ -1415,7 +1428,7 @@ hnsw_bit_support(PG_FUNCTION_ARGS)
 	};

 	PG_RETURN_POINTER(&typeInfo);
-}
+};

 FUNCTION_PREFIX PG_FUNCTION_INFO_V1(hnsw_sparsevec_support);
 Datum
@@ -1428,4 +1441,4 @@ hnsw_sparsevec_support(PG_FUNCTION_ARGS)
 	};

 	PG_RETURN_POINTER(&typeInfo);
-}
+};
--- a/src/hnswvacuum.c
+++ b/src/hnswvacuum.c
@@ -1,30 +1,21 @@
 #include "postgres.h"

-#include "access/genam.h"
+#include <math.h>
+
 #include "access/generic_xlog.h"
 #include "commands/vacuum.h"
 #include "hnsw.h"
-#include "nodes/pg_list.h"
 #include "storage/bufmgr.h"
 #include "storage/lmgr.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
-
-#if PG_VERSION_NUM >= 180000
-#define vacuum_delay_point() vacuum_delay_point(false)
-#endif

 /*
- * Check if deletion list contains an element
+ * Check if deleted list contains an index TID
 */
 static bool
-DeletingElement(tidhash_hash * deleting, ItemPointer indextid)
+DeletedContains(tidhash_hash * deleted, ItemPointer indextid)
 {
-	return tidhash_lookup(deleting, *indextid) != NULL;
+	return tidhash_lookup(deleted, *indextid) != NULL;
 }

 /*
@@ -37,20 +28,17 @@ RemoveHeapTids(HnswVacuumState * vacuumstate)
 {
 	BlockNumber blkno = HNSW_HEAD_BLKNO;
 	HnswElement highestPoint = &vacuumstate->highestPoint;
-	HnswElement fallbackPoint = &vacuumstate->fallbackPoint;
 	Relation	index = vacuumstate->index;
 	BufferAccessStrategy bas = vacuumstate->bas;
+	HnswElement entryPoint = HnswGetEntryPoint(vacuumstate->index);
 	IndexBulkDeleteResult *stats = vacuumstate->stats;

-	/* Store separately since HnswElement level is uint8 */
+	/* Store separately since highestPoint.level is uint8 */
 	int			highestLevel = -1;
-	int			fallbackLevel = -1;

-	/* Initialize highest point and fallback point */
+	/* Initialize highest point */
 	highestPoint->blkno = InvalidBlockNumber;
 	highestPoint->offno = InvalidOffsetNumber;
-	fallbackPoint->blkno = InvalidBlockNumber;
-	fallbackPoint->offno = InvalidOffsetNumber;

 	while (BlockNumberIsValid(blkno))
 	{
@@ -80,14 +68,6 @@ RemoveHeapTids(HnswVacuumState * vacuumstate)
 			if (!HnswIsElementTuple(etup))
 				continue;

-			/*
-			 * Skip deleted tuples. It is important they are not added to the
-			 * deletion list to avoid false positives in NeedsUpdated and
-			 * ConfirmRepaired.
-			 */
-			if (etup->deleted)
-				continue;
-
 			if (ItemPointerIsValid(&etup->heaptids[0]))
 			{
 				for (int i = 0; i < HNSW_HEAPTIDS; i++)
@@ -121,40 +101,23 @@ RemoveHeapTids(HnswVacuumState * vacuumstate)

 			if (!ItemPointerIsValid(&etup->heaptids[0]))
 			{
-				ItemPointerData indextid;
+				ItemPointerData ip;
 				bool		found;

-				/* Add to deletion list */
-				ItemPointerSet(&indextid, blkno, offno);
+				/* Add to deleted list */
+				ItemPointerSet(&ip, blkno, offno);

-				tidhash_insert(vacuumstate->deleting, indextid, &found);
+				tidhash_insert(vacuumstate->deleted, ip, &found);
 				Assert(!found);
 			}
-			else if (etup->level > highestLevel)
+			else if (etup->level > highestLevel && !(entryPoint != NULL && blkno == entryPoint->blkno && offno == entryPoint->offno))
 			{
-				if (BlockNumberIsValid(highestPoint->blkno))
-				{
-					/* Current highest point becomes fallback */
-					fallbackPoint->blkno = highestPoint->blkno;
-					fallbackPoint->offno = highestPoint->offno;
-					fallbackPoint->level = highestPoint->level;
-					fallbackLevel = highestLevel;
-				}
-
-				/* Keep track of highest point */
+				/* Keep track of highest non-entry point */
 				highestPoint->blkno = blkno;
 				highestPoint->offno = offno;
 				highestPoint->level = etup->level;
 				highestLevel = etup->level;
 			}
-			else if (etup->level > fallbackLevel)
-			{
-				/* Keep track of second highest point */
-				fallbackPoint->blkno = blkno;
-				fallbackPoint->offno = offno;
-				fallbackPoint->level = etup->level;
-				fallbackLevel = etup->level;
-			}
 		}

 		blkno = HnswPageGetOpaque(page)->nextblkno;
@@ -166,10 +129,6 @@ RemoveHeapTids(HnswVacuumState * vacuumstate)

 		UnlockReleaseBuffer(buf);
 	}
-
-#ifdef HNSW_MEMORY
-	elog(INFO, "memory: %zu KB", MemoryContextMemAllocated(CurrentMemoryContext, true) / 1024);
-#endif
 }

 /*
@@ -200,8 +159,8 @@ NeedsUpdated(HnswVacuumState * vacuumstate, HnswElement element)
 		if (!ItemPointerIsValid(indextid))
 			continue;

-		/* Check if in deletion list */
-		if (DeletingElement(vacuumstate->deleting, indextid))
+		/* Check if in deleted list */
+		if (DeletedContains(vacuumstate->deleted, indextid))
 		{
 			needsUpdated = true;
 			break;
@@ -210,8 +169,7 @@ NeedsUpdated(HnswVacuumState * vacuumstate, HnswElement element)

 	/* Also update if layer 0 is not full */
 	/* This could indicate too many candidates being deleted during insert */
-	/* There should always be more than zero indextids, but check for safety */
-	if (!needsUpdated && ntup->count > 0)
+	if (!needsUpdated)
 		needsUpdated = !ItemPointerIsValid(&ntup->indextids[ntup->count - 1]);

 	UnlockReleaseBuffer(buf);
@@ -297,27 +255,12 @@ RepairGraphEntryPoint(HnswVacuumState * vacuumstate)
 		/* Get a shared lock */
 		LockPage(index, HNSW_UPDATE_LOCK, ShareLock);

-		/* Get latest entry point */
-		entryPoint = HnswGetEntryPoint(index);
+		/* Load element */
+		HnswLoadElement(highestPoint, NULL, NULL, index, support, true, NULL);

-		/* Use fallback point if highest point is entry point */
-		if (entryPoint != NULL && entryPoint->blkno == highestPoint->blkno && entryPoint->offno == highestPoint->offno)
-		{
-			highestPoint = &vacuumstate->fallbackPoint;
-
-			if (!BlockNumberIsValid(highestPoint->blkno))
-				highestPoint = NULL;
-		}
-
-		if (highestPoint != NULL)
-		{
-			/* Load element */
-			HnswLoadElement(highestPoint, NULL, NULL, index, support, true, NULL);
-
-			/* Repair if needed */
-			if (NeedsUpdated(vacuumstate, highestPoint))
-				RepairGraphElement(vacuumstate, highestPoint, entryPoint);
-		}
+		/* Repair if needed */
+		if (NeedsUpdated(vacuumstate, highestPoint))
+			RepairGraphElement(vacuumstate, highestPoint, HnswGetEntryPoint(index));

 		/* Release lock */
 		UnlockPage(index, HNSW_UPDATE_LOCK, ShareLock);
@@ -335,7 +278,7 @@ RepairGraphEntryPoint(HnswVacuumState * vacuumstate)

 		ItemPointerSet(&epData, entryPoint->blkno, entryPoint->offno);

-		if (DeletingElement(vacuumstate->deleting, &epData))
+		if (DeletedContains(vacuumstate->deleted, &epData))
 		{
 			/*
 			 * Replace the entry point with the highest point. If highest
@@ -421,10 +364,6 @@ RepairGraph(HnswVacuumState * vacuumstate)
 			if (!HnswIsElementTuple(etup))
 				continue;

-			/* Skip deleted tuples */
-			if (etup->deleted)
-				continue;
-
 			/* Skip updating neighbors if being deleted */
 			if (!ItemPointerIsValid(&etup->heaptids[0]))
 				continue;
@@ -488,103 +427,6 @@ RepairGraph(HnswVacuumState * vacuumstate)
 		/* Reset memory context */
 		MemoryContextSwitchTo(oldCtx);
 		MemoryContextReset(vacuumstate->tmpCtx);
-
-#ifdef HNSW_VACUUM_PROGRESS
-		if (!BlockNumberIsValid(blkno) || (blkno - HNSW_HEAD_BLKNO) % 1000 == 0)
-		{
-			BlockNumber totalBlocks = RelationGetNumberOfBlocks(index);
-			BlockNumber currentBlocks = BlockNumberIsValid(blkno) ? blkno : totalBlocks;
-
-			elog(INFO, "hnsw vacuum progress: %.1f%%", 100.0 * currentBlocks / totalBlocks);
-		}
-#endif
-	}
-}
-
-/*
- * Confirm graph was repaired
- */
-static void
-ConfirmRepaired(HnswVacuumState * vacuumstate)
-{
-	BlockNumber blkno = HNSW_HEAD_BLKNO;
-	Relation	index = vacuumstate->index;
-	BufferAccessStrategy bas = vacuumstate->bas;
-
-	while (BlockNumberIsValid(blkno))
-	{
-		Buffer		buf;
-		Page		page;
-		OffsetNumber offno;
-		OffsetNumber maxoffno;
-
-		vacuum_delay_point();
-
-		buf = ReadBufferExtended(index, MAIN_FORKNUM, blkno, RBM_NORMAL, bas);
-		LockBuffer(buf, BUFFER_LOCK_SHARE);
-		page = BufferGetPage(buf);
-		maxoffno = PageGetMaxOffsetNumber(page);
-
-		/* Iterate over nodes */
-		for (offno = FirstOffsetNumber; offno <= maxoffno; offno = OffsetNumberNext(offno))
-		{
-			HnswElementTuple etup = (HnswElementTuple) PageGetItem(page, PageGetItemId(page, offno));
-			HnswNeighborTuple ntup;
-			Buffer		nbuf;
-			Page		npage;
-			BlockNumber neighborPage;
-			OffsetNumber neighborOffno;
-
-			/* Skip neighbor tuples */
-			if (!HnswIsElementTuple(etup))
-				continue;
-
-			/* Skip deleted tuples */
-			if (etup->deleted)
-				continue;
-
-			/* Skip if being deleted */
-			if (!ItemPointerIsValid(&etup->heaptids[0]))
-				continue;
-
-			/* Get neighbor page */
-			neighborPage = ItemPointerGetBlockNumber(&etup->neighbortid);
-			neighborOffno = ItemPointerGetOffsetNumber(&etup->neighbortid);
-
-			if (neighborPage == blkno)
-			{
-				nbuf = buf;
-				npage = page;
-			}
-			else
-			{
-				nbuf = ReadBufferExtended(index, MAIN_FORKNUM, neighborPage, RBM_NORMAL, bas);
-				LockBuffer(nbuf, BUFFER_LOCK_SHARE);
-				npage = BufferGetPage(nbuf);
-			}
-
-			ntup = (HnswNeighborTuple) PageGetItem(npage, PageGetItemId(npage, neighborOffno));
-
-			/* Check neighbors */
-			for (int i = 0; i < ntup->count; i++)
-			{
-				ItemPointer indextid = &ntup->indextids[i];
-
-				if (!ItemPointerIsValid(indextid))
-					continue;
-
-				/* Check if in deletion list */
-				if (DeletingElement(vacuumstate->deleting, indextid))
-					elog(ERROR, "hnsw graph not repaired");
-			}
-
-			if (nbuf != buf)
-				UnlockReleaseBuffer(nbuf);
-		}
-
-		blkno = HnswPageGetOpaque(page)->nextblkno;
-
-		UnlockReleaseBuffer(buf);
 	}
 }

@@ -600,15 +442,10 @@ MarkDeleted(HnswVacuumState * vacuumstate)
 	BufferAccessStrategy bas = vacuumstate->bas;

 	/*
-	 * Wait for inserts and index scans to complete. Inserts and scans before
-	 * this point may visit tuples about to be deleted. Inserts and scans
-	 * after this point will not, since the graph has been repaired.
+	 * Wait for index scans to complete. Scans before this point may contain
+	 * tuples about to be deleted. Scans after this point will not, since the
+	 * graph has been repaired.
 	 */
-	LockPage(index, HNSW_UPDATE_LOCK, ExclusiveLock);
-	UnlockPage(index, HNSW_UPDATE_LOCK, ExclusiveLock);
-
-	ConfirmRepaired(vacuumstate);
-
 	LockPage(index, HNSW_SCAN_LOCK, ExclusiveLock);
 	UnlockPage(index, HNSW_SCAN_LOCK, ExclusiveLock);

@@ -683,9 +520,8 @@ MarkDeleted(HnswVacuumState * vacuumstate)
 			ntup = (HnswNeighborTuple) PageGetItem(npage, PageGetItemId(npage, neighborOffno));

 			/* Overwrite element */
-			/* Use memset instead of MemSet to keep clang-tidy happy */
 			etup->deleted = 1;
-			memset(&etup->data, 0, VARSIZE_ANY(&etup->data));
+			MemSet(&etup->data, 0, VARSIZE_ANY(&etup->data));

 			/* Overwrite neighbors */
 			for (int i = 0; i < ntup->count; i++)
@@ -756,7 +592,7 @@ InitVacuumState(HnswVacuumState * vacuumstate, IndexVacuumInfo *info, IndexBulkD
 	HnswGetMetaPageInfo(index, &vacuumstate->m, NULL);

 	/* Create hash table */
-	vacuumstate->deleting = tidhash_create(CurrentMemoryContext, 256, NULL);
+	vacuumstate->deleted = tidhash_create(CurrentMemoryContext, 256, NULL);
 }

 /*
@@ -765,7 +601,7 @@ InitVacuumState(HnswVacuumState * vacuumstate, IndexVacuumInfo *info, IndexBulkD
 static void
 FreeVacuumState(HnswVacuumState * vacuumstate)
 {
-	tidhash_destroy(vacuumstate->deleting);
+	tidhash_destroy(vacuumstate->deleted);
 	FreeAccessStrategy(vacuumstate->bas);
 	pfree(vacuumstate->ntup);
 	MemoryContextDelete(vacuumstate->tmpCtx);
@@ -783,13 +619,13 @@ hnswbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
 	InitVacuumState(&vacuumstate, info, stats, callback, callback_state);

 	/* Pass 1: Remove heap TIDs */
-	HnswBench("RemoveHeapTids", RemoveHeapTids(&vacuumstate));
+	RemoveHeapTids(&vacuumstate);

 	/* Pass 2: Repair graph */
-	HnswBench("RepairGraph", RepairGraph(&vacuumstate));
+	RepairGraph(&vacuumstate);

-	/* Passes 3 and 4: Confirm repaired and mark as deleted */
-	HnswBench("MarkDeleted", MarkDeleted(&vacuumstate));
+	/* Pass 3: Mark as deleted */
+	MarkDeleted(&vacuumstate);

 	FreeVacuumState(&vacuumstate);

--- a/src/intvec.c
+++ b/src/intvec.c
@@ -0,0 +1,754 @@
+#include "postgres.h"
+
+#include <limits.h>
+#include <math.h>
+
+#include "catalog/pg_type.h"
+#include "fmgr.h"
+#include "intvec.h"
+#include "lib/stringinfo.h"
+#include "libpq/pqformat.h"
+#include "utils/array.h"
+#include "utils/builtins.h"
+#include "utils/lsyscache.h"
+
+/*
+ * Ensure same dimensions
+ */
+static inline void
+CheckDims(IntVector * a, IntVector * b)
+{
+	if (a->dim != b->dim)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("different intvec dimensions %d and %d", a->dim, b->dim)));
+}
+
+/*
+ * Ensure expected dimensions
+ */
+static inline void
+CheckExpectedDim(int32 typmod, int dim)
+{
+	if (typmod != -1 && typmod != dim)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("expected %d dimensions, not %d", typmod, dim)));
+}
+
+/*
+ * Ensure valid dimensions
+ */
+static inline void
+CheckDim(int dim)
+{
+	if (dim < 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("intvec must have at least 1 dimension")));
+
+	if (dim > INTVEC_MAX_DIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("intvec cannot have more than %d dimensions", INTVEC_MAX_DIM)));
+}
+
+/*
+ * Ensure element in range
+ */
+static inline void
+CheckElement(long value)
+{
+	if (value < SCHAR_MIN || value > SCHAR_MAX)
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("value \"%ld\" is out of range for type intvec", value)));
+}
+
+/*
+ * Allocate and initialize a new int vector
+ */
+IntVector *
+InitIntVector(int dim)
+{
+	IntVector  *result;
+	int			size;
+
+	size = INTVEC_SIZE(dim);
+	result = (IntVector *) palloc0(size);
+	SET_VARSIZE(result, size);
+	result->dim = dim;
+
+	return result;
+}
+
+/*
+ * Check for whitespace, since array_isspace() is static
+ */
+static inline bool
+intvec_isspace(char ch)
+{
+	if (ch == ' ' ||
+		ch == '\t' ||
+		ch == '\n' ||
+		ch == '\r' ||
+		ch == '\v' ||
+		ch == '\f')
+		return true;
+	return false;
+}
+
+/*
+ * Convert textual representation to internal representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_in);
+Datum
+intvec_in(PG_FUNCTION_ARGS)
+{
+	char	   *lit = PG_GETARG_CSTRING(0);
+	int32		typmod = PG_GETARG_INT32(2);
+	int8		x[INTVEC_MAX_DIM];
+	int			dim = 0;
+	char	   *pt = lit;
+	IntVector  *result;
+
+	while (intvec_isspace(*pt))
+		pt++;
+
+	if (*pt != '[')
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+				 errmsg("invalid input syntax for type intvec: \"%s\"", lit),
+				 errdetail("Vector contents must start with \"[\".")));
+
+	pt++;
+
+	while (intvec_isspace(*pt))
+		pt++;
+
+	if (*pt == ']')
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("intvec must have at least 1 dimension")));
+
+	for (;;)
+	{
+		long		val;
+		char	   *stringEnd;
+
+		if (dim == INTVEC_MAX_DIM)
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg("intvec cannot have more than %d dimensions", VECTOR_MAX_DIM)));
+
+		while (intvec_isspace(*pt))
+			pt++;
+
+		/* Check for empty string like float4in */
+		if (*pt == '\0')
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("invalid input syntax for type intvec: \"%s\"", lit)));
+
+		errno = 0;
+
+		/* Use similar logic as int2vectorin */
+		val = strtol(pt, &stringEnd, 10);
+
+		if (stringEnd == pt)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("invalid input syntax for type intvec: \"%s\"", lit)));
+
+		/* Check for range error like float4in */
+		if (errno == ERANGE || val < SCHAR_MIN || val > SCHAR_MAX)
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("\"%s\" is out of range for type intvec", pnstrdup(pt, stringEnd - pt))));
+
+		CheckElement(val);
+		x[dim++] = val;
+
+		pt = stringEnd;
+
+		while (intvec_isspace(*pt))
+			pt++;
+
+		if (*pt == ',')
+			pt++;
+		else if (*pt == ']')
+		{
+			pt++;
+			break;
+		}
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("invalid input syntax for type intvec: \"%s\"", lit)));
+	}
+
+	/* Only whitespace is allowed after the closing brace */
+	while (intvec_isspace(*pt))
+		pt++;
+
+	if (*pt != '\0')
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+				 errmsg("invalid input syntax for type intvec: \"%s\"", lit),
+				 errdetail("Junk after closing right brace.")));
+
+	CheckDim(dim);
+	CheckExpectedDim(typmod, dim);
+
+	result = InitIntVector(dim);
+	for (int i = 0; i < dim; i++)
+		result->x[i] = x[i];
+
+	PG_RETURN_POINTER(result);
+}
+
+/*
+ * Convert internal representation to textual representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_out);
+Datum
+intvec_out(PG_FUNCTION_ARGS)
+{
+	IntVector  *vector = PG_GETARG_INTVEC_P(0);
+	int			dim = vector->dim;
+	char	   *buf;
+	char	   *ptr;
+
+	/*
+	 * Need:
+	 *
+	 * dim * 4 bytes for elements (-128 to 127)
+	 *
+	 * dim - 1 bytes for separator
+	 *
+	 * 3 bytes for [, ], and \0
+	 */
+	buf = (char *) palloc(5 * dim + 2);
+	ptr = buf;
+
+	*ptr = '[';
+	ptr++;
+	for (int i = 0; i < dim; i++)
+	{
+		if (i > 0)
+		{
+			*ptr = ',';
+			ptr++;
+		}
+
+#if PG_VERSION_NUM >= 140000
+		ptr += pg_ltoa(vector->x[i], ptr);
+#else
+		pg_ltoa(vector->x[i], ptr);
+		while (*ptr != '\0')
+			ptr++;
+#endif
+	}
+	*ptr = ']';
+	ptr++;
+	*ptr = '\0';
+
+	PG_FREE_IF_COPY(vector, 0);
+	PG_RETURN_CSTRING(buf);
+}
+
+/*
+ * Convert type modifier
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_typmod_in);
+Datum
+intvec_typmod_in(PG_FUNCTION_ARGS)
+{
+	ArrayType  *ta = PG_GETARG_ARRAYTYPE_P(0);
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	if (*tl < 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("dimensions for type intvec must be at least 1")));
+
+	if (*tl > INTVEC_MAX_DIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("dimensions for type intvec cannot exceed %d", INTVEC_MAX_DIM)));
+
+	PG_RETURN_INT32(*tl);
+}
+
+/*
+ * Convert external binary representation to internal representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_recv);
+Datum
+intvec_recv(PG_FUNCTION_ARGS)
+{
+	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+	int32		typmod = PG_GETARG_INT32(2);
+	IntVector  *result;
+	int16		dim;
+	int16		unused;
+
+	dim = pq_getmsgint(buf, sizeof(int16));
+	unused = pq_getmsgint(buf, sizeof(int16));
+
+	CheckDim(dim);
+	CheckExpectedDim(typmod, dim);
+
+	if (unused != 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("expected unused to be 0, not %d", unused)));
+
+	result = InitIntVector(dim);
+	for (int i = 0; i < dim; i++)
+		result->x[i] = pq_getmsgint(buf, sizeof(int8));
+
+	PG_RETURN_POINTER(result);
+}
+
+/*
+ * Convert internal representation to the external binary representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_send);
+Datum
+intvec_send(PG_FUNCTION_ARGS)
+{
+	IntVector  *vec = PG_GETARG_INTVEC_P(0);
+	StringInfoData buf;
+
+	pq_begintypsend(&buf);
+	pq_sendint(&buf, vec->dim, sizeof(int16));
+	pq_sendint(&buf, vec->unused, sizeof(int16));
+	for (int i = 0; i < vec->dim; i++)
+		pq_sendint8(&buf, vec->x[i]);
+
+	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+/*
+ * Convert int vector to int vector
+ * This is needed to check the type modifier
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec);
+Datum
+intvec(PG_FUNCTION_ARGS)
+{
+	IntVector  *vec = PG_GETARG_INTVEC_P(0);
+	int32		typmod = PG_GETARG_INT32(1);
+
+	CheckExpectedDim(typmod, vec->dim);
+
+	PG_RETURN_POINTER(vec);
+}
+
+/*
+ * Convert array to intvec vector
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(array_to_intvec);
+Datum
+array_to_intvec(PG_FUNCTION_ARGS)
+{
+	ArrayType  *array = PG_GETARG_ARRAYTYPE_P(0);
+	int32		typmod = PG_GETARG_INT32(1);
+	IntVector  *result;
+	int16		typlen;
+	bool		typbyval;
+	char		typalign;
+	Datum	   *elemsp;
+	int			nelemsp;
+
+	if (ARR_NDIM(array) > 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("array must be 1-D")));
+
+	if (ARR_HASNULL(array) && array_contains_nulls(array))
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("array must not contain nulls")));
+
+	get_typlenbyvalalign(ARR_ELEMTYPE(array), &typlen, &typbyval, &typalign);
+	deconstruct_array(array, ARR_ELEMTYPE(array), typlen, typbyval, typalign, &elemsp, NULL, &nelemsp);
+
+	CheckDim(nelemsp);
+	CheckExpectedDim(typmod, nelemsp);
+
+	result = InitIntVector(nelemsp);
+
+	if (ARR_ELEMTYPE(array) == INT4OID)
+	{
+		for (int i = 0; i < nelemsp; i++)
+		{
+			long		l = DatumGetInt32(elemsp[i]);
+
+			CheckElement(l);
+
+			result->x[i] = l;
+		}
+	}
+	else
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("unsupported array type")));
+	}
+
+	/*
+	 * Free allocation from deconstruct_array. Do not free individual elements
+	 * when pass-by-reference since they point to original array.
+	 */
+	pfree(elemsp);
+
+	PG_RETURN_POINTER(result);
+}
+
+/*
+ * Convert int vector to integer[]
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_to_integer);
+Datum
+intvec_to_integer(PG_FUNCTION_ARGS)
+{
+	IntVector  *vec = PG_GETARG_INTVEC_P(0);
+	Datum	   *datums;
+	ArrayType  *result;
+
+	datums = (Datum *) palloc(sizeof(Datum) * vec->dim);
+
+	for (int i = 0; i < vec->dim; i++)
+		datums[i] = Int32GetDatum((int) vec->x[i]);
+
+	result = construct_array(datums, vec->dim, INT4OID, sizeof(int32), true, TYPALIGN_INT);
+
+	pfree(datums);
+
+	PG_RETURN_POINTER(result);
+}
+
+static int
+IntvecL2SquaredDistance(int dim, int8 *ax, int8 *bx)
+{
+	int			distance = 0;
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+	{
+		int			diff = (int) ax[i] - (int) bx[i];
+
+		distance += diff * diff;
+	}
+
+	return distance;
+}
+
+/*
+ * Get the L2 distance between int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_l2_distance);
+Datum
+intvec_l2_distance(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	CheckDims(a, b);
+
+	PG_RETURN_FLOAT8(sqrt((double) IntvecL2SquaredDistance(a->dim, a->x, b->x)));
+}
+
+/*
+ * Get the L2 squared distance between int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_l2_squared_distance);
+Datum
+intvec_l2_squared_distance(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	CheckDims(a, b);
+
+	PG_RETURN_FLOAT8((double) IntvecL2SquaredDistance(a->dim, a->x, b->x));
+}
+
+static int
+IntvecInnerProduct(int dim, int8 *ax, int8 *bx)
+{
+	int			distance = 0;
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+		distance += (int) ax[i] * (int) bx[i];
+
+	return distance;
+}
+
+/*
+ * Get the inner product of two int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_inner_product);
+Datum
+intvec_inner_product(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	CheckDims(a, b);
+
+	PG_RETURN_FLOAT8((double) IntvecInnerProduct(a->dim, a->x, b->x));
+}
+
+/*
+ * Get the negative inner product of two int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_negative_inner_product);
+Datum
+intvec_negative_inner_product(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	CheckDims(a, b);
+
+	PG_RETURN_FLOAT8((double) -IntvecInnerProduct(a->dim, a->x, b->x));
+}
+
+static double
+IntvecCosineSimilarity(int dim, int8 *ax, int8 *bx)
+{
+	int			similarity = 0;
+	int			norma = 0;
+	int			normb = 0;
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+	{
+		int			axi = ax[i];
+		int			bxi = bx[i];
+
+		similarity += axi * bxi;
+		norma += axi * axi;
+		normb += bxi * bxi;
+	}
+
+	/* Use sqrt(a * b) over sqrt(a) * sqrt(b) */
+	return (double) similarity / sqrt((double) norma * (double) normb);
+}
+
+/*
+ * Get the cosine distance between two int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_cosine_distance);
+Datum
+intvec_cosine_distance(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+	double		similarity;
+
+	CheckDims(a, b);
+
+	similarity = IntvecCosineSimilarity(a->dim, a->x, b->x);
+
+#ifdef _MSC_VER
+	/* /fp:fast may not propagate NaN */
+	if (isnan(similarity))
+		PG_RETURN_FLOAT8(NAN);
+#endif
+
+	/* Keep in range */
+	if (similarity > 1)
+		similarity = 1;
+	else if (similarity < -1)
+		similarity = -1;
+
+	PG_RETURN_FLOAT8(1 - similarity);
+}
+
+static int
+IntvecL1Distance(int dim, int8 *ax, int8 *bx)
+{
+	int			distance = 0;
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+		distance += abs((int) ax[i] - (int) bx[i]);
+
+	return distance;
+}
+
+/*
+ * Get the L1 distance between two int vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_l1_distance);
+Datum
+intvec_l1_distance(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	CheckDims(a, b);
+
+	PG_RETURN_FLOAT8((double) IntvecL1Distance(a->dim, a->x, b->x));
+}
+
+/*
+ * Get the dimensions of an int vector
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_vector_dims);
+Datum
+intvec_vector_dims(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+
+	PG_RETURN_INT32(a->dim);
+}
+
+/*
+ * Get the L2 norm of an int vector
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(intvec_l2_norm);
+Datum
+intvec_l2_norm(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	int8	   *ax = a->x;
+	int			norm = 0;
+
+	/* Auto-vectorized */
+	for (int i = 0; i < a->dim; i++)
+		norm += (int) ax[i] * (int) ax[i];
+
+	PG_RETURN_FLOAT8(sqrt((double) norm));
+}
+
+/*
+ * Internal helper to compare int vectors
+ */
+static int
+intvec_cmp_internal(IntVector * a, IntVector * b)
+{
+	int			dim = Min(a->dim, b->dim);
+
+	/* Check values before dimensions to be consistent with Postgres arrays */
+	for (int i = 0; i < dim; i++)
+	{
+		if (a->x[i] < b->x[i])
+			return -1;
+
+		if (a->x[i] > b->x[i])
+			return 1;
+	}
+
+	if (a->dim < b->dim)
+		return -1;
+
+	if (a->dim > b->dim)
+		return 1;
+
+	return 0;
+}
+
+/*
+ * Less than
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_lt);
+Datum
+intvec_lt(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) < 0);
+}
+
+/*
+ * Less than or equal
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_le);
+Datum
+intvec_le(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) <= 0);
+}
+
+/*
+ * Equal
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_eq);
+Datum
+intvec_eq(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) == 0);
+}
+
+/*
+ * Not equal
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_ne);
+Datum
+intvec_ne(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) != 0);
+}
+
+/*
+ * Greater than or equal
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_ge);
+Datum
+intvec_ge(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) >= 0);
+}
+
+/*
+ * Greater than
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_gt);
+Datum
+intvec_gt(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_BOOL(intvec_cmp_internal(a, b) > 0);
+}
+
+/*
+ * Compare int vectors
+ */
+FUNCTION_PREFIX PG_FUNCTION_INFO_V1(intvec_cmp);
+Datum
+intvec_cmp(PG_FUNCTION_ARGS)
+{
+	IntVector  *a = PG_GETARG_INTVEC_P(0);
+	IntVector  *b = PG_GETARG_INTVEC_P(1);
+
+	PG_RETURN_INT32(intvec_cmp_internal(a, b));
+}
--- a/src/intvec.h
+++ b/src/intvec.h
@@ -0,0 +1,23 @@
+#ifndef INTVEC_H
+#define INTVEC_H
+
+#include "vector.h"
+
+#define INTVEC_MAX_DIM VECTOR_MAX_DIM
+
+#define INTVEC_SIZE(_dim)		(offsetof(IntVector, x) + sizeof(int8)*(_dim))
+#define DatumGetIntVector(x)	((IntVector *) PG_DETOAST_DATUM(x))
+#define PG_GETARG_INTVEC_P(x)	DatumGetIntVector(PG_GETARG_DATUM(x))
+#define PG_RETURN_INTVEC_P(x)	PG_RETURN_POINTER(x)
+
+typedef struct IntVector
+{
+	int32		vl_len_;		/* varlena header (do not touch directly!) */
+	int16		dim;			/* number of dimensions */
+	int16		unused;
+	int8		x[FLEXIBLE_ARRAY_MEMBER];
+}			IntVector;
+
+IntVector  *InitIntVector(int dim);
+
+#endif
--- a/src/ivfbuild.c
+++ b/src/ivfbuild.c
@@ -2,37 +2,23 @@

 #include <float.h>

-#include "access/genam.h"
-#include "access/generic_xlog.h"
-#include "access/itup.h"
-#include "access/relscan.h"
 #include "access/table.h"
 #include "access/tableam.h"
-#include "access/tupdesc.h"
 #include "access/parallel.h"
 #include "access/xact.h"
-#include "access/xloginsert.h"
+#include "bitvec.h"
 #include "catalog/index.h"
 #include "catalog/pg_operator_d.h"
 #include "catalog/pg_type_d.h"
 #include "commands/progress.h"
-#include "fmgr.h"
+#include "halfvec.h"
 #include "ivfflat.h"
 #include "miscadmin.h"
-#include "nodes/execnodes.h"
 #include "optimizer/optimizer.h"
 #include "storage/bufmgr.h"
-#include "storage/condition_variable.h"
 #include "tcop/tcopprot.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"
-#include "utils/sampling.h"
-#include "utils/snapmgr.h"
-#include "utils/tuplesort.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
+#include "vector.h"

 #if PG_VERSION_NUM >= 140000
 #include "utils/backend_progress.h"
@@ -63,13 +49,15 @@ AddSample(Datum *values, IvfflatBuildState * buildstate)
 	Datum		value = PointerGetDatum(PG_DETOAST_DATUM(values[0]));

 	/*
-	 * Check with KMEANS_NORM_PROC that the value can be normalized since
-	 * spherical distance function expects unit vectors
+	 * Normalize with KMEANS_NORM_PROC since spherical distance function
+	 * expects unit vectors
 	 */
 	if (buildstate->kmeansnormprocinfo != NULL)
 	{
 		if (!IvfflatCheckNorm(buildstate->kmeansnormprocinfo, buildstate->collation, value))
 			return;
+
+		value = IvfflatNormValue(buildstate->typeInfo, buildstate->collation, value);
 	}

 	if (samples->length < targsamples)
@@ -80,7 +68,7 @@ AddSample(Datum *values, IvfflatBuildState * buildstate)
 	else
 	{
 		if (buildstate->rowstoskip < 0)
-			buildstate->rowstoskip = reservoir_get_next_S(&buildstate->rstate, buildstate->samplerows, targsamples);
+			buildstate->rowstoskip = reservoir_get_next_S(&buildstate->rstate, samples->length, targsamples);

 		if (buildstate->rowstoskip <= 0)
 		{
@@ -96,9 +84,6 @@ AddSample(Datum *values, IvfflatBuildState * buildstate)

 		buildstate->rowstoskip -= 1;
 	}
-
-	/* Increment after reservoir_get_next_S */
-	buildstate->samplerows += 1;
 }

 /*
@@ -135,7 +120,6 @@ SampleRows(IvfflatBuildState * buildstate)
 	int			targsamples = buildstate->samples->maxlen;
 	BlockNumber totalblocks = RelationGetNumberOfBlocks(buildstate->heap);

-	buildstate->samplerows = 0;
 	buildstate->rowstoskip = -1;

 	BlockSampler_Init(&buildstate->bs, totalblocks, targsamples, RandomInt());
@@ -145,21 +129,16 @@ SampleRows(IvfflatBuildState * buildstate)
 	{
 		BlockNumber targblock = BlockSampler_Next(&buildstate->bs);

-		/* Set anyvisible to false like table_index_build_scan */
 		table_index_build_range_scan(buildstate->heap, buildstate->index, buildstate->indexInfo,
-									 false, false, false, targblock, 1, SampleCallback, (void *) buildstate, NULL);
+									 false, true, false, targblock, 1, SampleCallback, (void *) buildstate, NULL);
 	}
-
-	/* Normalize if needed */
-	if (buildstate->kmeansnormprocinfo != NULL)
-		IvfflatNormVectors(buildstate->typeInfo, buildstate->collation, buildstate->samples, buildstate->tmpCtx);
 }

 /*
 * Add tuple to sort
 */
 static void
-AddTupleToSort(ItemPointer tid, Datum *values, IvfflatBuildState * buildstate)
+AddTupleToSort(Relation index, ItemPointer tid, Datum *values, IvfflatBuildState * buildstate)
 {
 	double		distance;
 	double		minDistance = DBL_MAX;
@@ -236,7 +215,7 @@ BuildCallback(Relation index, ItemPointer tid, Datum *values,
 	oldCtx = MemoryContextSwitchTo(buildstate->tmpCtx);

 	/* Add tuple to sort */
-	AddTupleToSort(tid, values, buildstate);
+	AddTupleToSort(index, tid, values, buildstate);

 	/* Reset memory context */
 	MemoryContextSwitchTo(oldCtx);
@@ -381,21 +360,11 @@ InitBuildState(IvfflatBuildState * buildstate, Relation heap, Relation index, In
 	buildstate->sortdesc = CreateTemplateTupleDesc(3);
 	TupleDescInitEntry(buildstate->sortdesc, (AttrNumber) 1, "list", INT4OID, -1, 0);
 	TupleDescInitEntry(buildstate->sortdesc, (AttrNumber) 2, "tid", TIDOID, -1, 0);
-	TupleDescInitEntry(buildstate->sortdesc, (AttrNumber) 3, "vector", TupleDescAttr(buildstate->tupdesc, 0)->atttypid, -1, 0);
-#if PG_VERSION_NUM >= 190000
-	TupleDescFinalize(buildstate->sortdesc);
-#endif
+	TupleDescInitEntry(buildstate->sortdesc, (AttrNumber) 3, "vector", buildstate->tupdesc->attrs[0].atttypid, -1, 0);

 	buildstate->slot = MakeSingleTupleTableSlot(buildstate->sortdesc, &TTSOpsVirtual);

-	buildstate->memoryUsed = 0;
-	buildstate->itemsize = buildstate->typeInfo->itemSize(buildstate->dimensions);
-
-	buildstate->memoryUsed += VECTOR_ARRAY_SIZE(buildstate->lists, buildstate->itemsize);
-	IvfflatCheckMemoryUsage(buildstate->memoryUsed);
-	buildstate->centers = VectorArrayInit(buildstate->lists, buildstate->dimensions, buildstate->itemsize);
-
-	/* TODO Move allocation to page creation */
+	buildstate->centers = VectorArrayInit(buildstate->lists, buildstate->dimensions, buildstate->typeInfo->itemSize(buildstate->dimensions));
 	buildstate->listInfo = palloc(sizeof(ListInfo) * buildstate->lists);

 	buildstate->tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
@@ -449,12 +418,11 @@ ComputeCenters(IvfflatBuildState * buildstate)
 		numSamples = 1;

 	/* Sample rows */
-	buildstate->memoryUsed += VECTOR_ARRAY_SIZE(numSamples, buildstate->itemsize);
-	IvfflatCheckMemoryUsage(buildstate->memoryUsed);
-	buildstate->samples = VectorArrayInit(numSamples, buildstate->dimensions, buildstate->itemsize);
+	/* TODO Ensure within maintenance_work_mem */
+	buildstate->samples = VectorArrayInit(numSamples, buildstate->dimensions, buildstate->centers->itemsize);
 	if (buildstate->heap != NULL)
 	{
-		IvfflatBench("sample rows", SampleRows(buildstate));
+		SampleRows(buildstate);

 		if (buildstate->samples->length < buildstate->lists)
 		{
@@ -466,7 +434,7 @@ ComputeCenters(IvfflatBuildState * buildstate)
 	}

 	/* Calculate centers */
-	IvfflatBench("k-means", IvfflatKmeans(buildstate->index, buildstate->samples, buildstate->centers, buildstate->typeInfo, buildstate->memoryUsed));
+	IvfflatBench("k-means", IvfflatKmeans(buildstate->index, buildstate->samples, buildstate->centers, buildstate->typeInfo));

 	/* Free samples before we allocate more memory */
 	VectorArrayFree(buildstate->samples);
@@ -502,8 +470,8 @@ CreateMetaPage(Relation index, int dimensions, int lists, ForkNumber forkNum)
 * Create list pages
 */
 static void
-CreateListPages(Relation index, VectorArray centers, int lists,
-				ForkNumber forkNum, ListInfo * *listInfo)
+CreateListPages(Relation index, VectorArray centers, int dimensions,
+				int lists, ForkNumber forkNum, ListInfo * *listInfo)
 {
 	Buffer		buf;
 	Page		page;
@@ -669,11 +637,7 @@ IvfflatParallelScanAndSort(IvfflatSpool * ivfspool, IvfflatShared * ivfshared, S
 	ivfspool->sortstate = InitBuildSortState(buildstate.sortdesc, sortmem, coordinate);
 	buildstate.sortstate = ivfspool->sortstate;
 	scan = table_beginscan_parallel(ivfspool->heap,
-									ParallelTableScanFromIvfflatShared(ivfshared)
-#if PG_VERSION_NUM >= 190000
-									,SO_NONE
-#endif
-		);
+									ParallelTableScanFromIvfflatShared(ivfshared));
 	reltuples = table_index_build_scan(ivfspool->heap, ivfspool->index, indexInfo,
 									   true, progress, BuildCallback,
 									   (void *) &buildstate, scan);
@@ -1040,7 +1004,7 @@ BuildIndex(Relation heap, Relation index, IndexInfo *indexInfo,

 	/* Create pages */
 	CreateMetaPage(index, buildstate->dimensions, buildstate->lists, forkNum);
-	CreateListPages(index, buildstate->centers, buildstate->lists, forkNum, &buildstate->listInfo);
+	CreateListPages(index, buildstate->centers, buildstate->dimensions, buildstate->lists, forkNum, &buildstate->listInfo);
 	CreateEntryPages(buildstate, forkNum);

 	/* Write WAL for initialization fork since GenericXLog functions do not */
@@ -1059,10 +1023,6 @@ ivfflatbuild(Relation heap, Relation index, IndexInfo *indexInfo)
 	IndexBuildResult *result;
 	IvfflatBuildState buildstate;

-#ifdef IVFFLAT_BENCH
-	SeedRandom(42);
-#endif
-
 	BuildIndex(heap, index, indexInfo, &buildstate, MAIN_FORKNUM);

 	result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
--- a/src/ivfflat.c
+++ b/src/ivfflat.c
@@ -3,32 +3,27 @@
 #include <float.h>

 #include "access/amapi.h"
-#include "access/genam.h"
 #include "access/reloptions.h"
 #include "commands/progress.h"
 #include "commands/vacuum.h"
-#include "fmgr.h"
 #include "ivfflat.h"
-#include "nodes/pg_list.h"
 #include "utils/float.h"
 #include "utils/guc.h"
-#include "utils/relcache.h"
 #include "utils/selfuncs.h"
 #include "utils/spccache.h"
-#include "vector.h"

 #if PG_VERSION_NUM < 150000
 #define MarkGUCPrefixReserved(x) EmitWarningsOnPlaceholders(x)
 #endif

 int			ivfflat_probes;
-int			ivfflat_iterative_scan;
+int			ivfflat_iterative_search;
 int			ivfflat_max_probes;
 static relopt_kind ivfflat_relopt_kind;

-static const struct config_enum_entry ivfflat_iterative_scan_options[] = {
-	{"off", IVFFLAT_ITERATIVE_SCAN_OFF, false},
-	{"relaxed_order", IVFFLAT_ITERATIVE_SCAN_RELAXED, false},
+static const struct config_enum_entry ivfflat_iterative_search_options[] = {
+	{"off", IVFFLAT_ITERATIVE_SEARCH_OFF, false},
+	{"relaxed_order", IVFFLAT_ITERATIVE_SEARCH_RELAXED, false},
 	{NULL, 0, false}
 };

@@ -46,14 +41,14 @@ IvfflatInit(void)
 							"Valid range is 1..lists.", &ivfflat_probes,
 							IVFFLAT_DEFAULT_PROBES, IVFFLAT_MIN_LISTS, IVFFLAT_MAX_LISTS, PGC_USERSET, 0, NULL, NULL, NULL);

-	DefineCustomEnumVariable("ivfflat.iterative_scan", "Sets the mode for iterative scans",
-							 NULL, &ivfflat_iterative_scan,
-							 IVFFLAT_ITERATIVE_SCAN_OFF, ivfflat_iterative_scan_options, PGC_USERSET, 0, NULL, NULL, NULL);
+	DefineCustomEnumVariable("ivfflat.iterative_search", "Sets the iterative search mode",
+							 NULL, &ivfflat_iterative_search,
+							 IVFFLAT_ITERATIVE_SEARCH_OFF, ivfflat_iterative_search_options, PGC_USERSET, 0, NULL, NULL, NULL);

 	/* If this is less than probes, probes is used */
-	DefineCustomIntVariable("ivfflat.max_probes", "Sets the max number of probes for iterative scans",
-							NULL, &ivfflat_max_probes,
-							IVFFLAT_MAX_LISTS, IVFFLAT_MIN_LISTS, IVFFLAT_MAX_LISTS, PGC_USERSET, 0, NULL, NULL, NULL);
+	DefineCustomIntVariable("ivfflat.max_probes", "Sets the max number of probes for iterative search",
+							"-1 means no limit", &ivfflat_max_probes,
+							-1, -1, IVFFLAT_MAX_LISTS, PGC_USERSET, 0, NULL, NULL, NULL);

 	MarkGUCPrefixReserved("ivfflat");
 }
@@ -97,17 +92,13 @@ ivfflatcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	Relation	index;

 	/* Never use index without order */
-	if (path->indexorderbys == NIL)
+	if (path->indexorderbys == NULL)
 	{
 		*indexStartupCost = get_float8_infinity();
 		*indexTotalCost = get_float8_infinity();
 		*indexSelectivity = 0;
 		*indexCorrelation = 0;
 		*indexPages = 0;
-#if PG_VERSION_NUM >= 180000
-		/* See "On disable_cost" thread on pgsql-hackers */
-		path->path.disabled_nodes = 2;
-#endif
 		return;
 	}

@@ -184,64 +175,6 @@ FUNCTION_PREFIX PG_FUNCTION_INFO_V1(ivfflathandler);
 Datum
 ivfflathandler(PG_FUNCTION_ARGS)
 {
-#if PG_VERSION_NUM >= 190000
-	static const IndexAmRoutine amroutine = {
-		.type = T_IndexAmRoutine,
-		.amstrategies = 0,
-		.amsupport = 5,
-		.amoptsprocnum = 0,
-		.amcanorder = false,
-		.amcanorderbyop = true,
-		.amcanhash = false,
-		.amconsistentequality = false,
-		.amconsistentordering = false,
-		.amcanbackward = false,
-		.amcanunique = false,
-		.amcanmulticol = false,
-		.amoptionalkey = true,
-		.amsearcharray = false,
-		.amsearchnulls = false,
-		.amstorage = false,
-		.amclusterable = false,
-		.ampredlocks = false,
-		.amcanparallel = false,
-		.amcanbuildparallel = true,
-		.amcaninclude = false,
-		.amusemaintenanceworkmem = false,
-		.amsummarizing = false,
-		.amparallelvacuumoptions = VACUUM_OPTION_PARALLEL_BULKDEL,
-		.amkeytype = InvalidOid,
-
-		.ambuild = ivfflatbuild,
-		.ambuildempty = ivfflatbuildempty,
-		.aminsert = ivfflatinsert,
-		.aminsertcleanup = NULL,
-		.ambulkdelete = ivfflatbulkdelete,
-		.amvacuumcleanup = ivfflatvacuumcleanup,
-		.amcanreturn = NULL,
-		.amcostestimate = ivfflatcostestimate,
-		.amgettreeheight = NULL,
-		.amoptions = ivfflatoptions,
-		.amproperty = NULL,
-		.ambuildphasename = ivfflatbuildphasename,
-		.amvalidate = ivfflatvalidate,
-		.amadjustmembers = NULL,
-		.ambeginscan = ivfflatbeginscan,
-		.amrescan = ivfflatrescan,
-		.amgettuple = ivfflatgettuple,
-		.amgetbitmap = NULL,
-		.amendscan = ivfflatendscan,
-		.ammarkpos = NULL,
-		.amrestrpos = NULL,
-		.amestimateparallelscan = NULL,
-		.aminitparallelscan = NULL,
-		.amparallelrescan = NULL,
-		.amtranslatestrategy = NULL,
-		.amtranslatecmptype = NULL,
-	};
-
-	PG_RETURN_POINTER(&amroutine);
-#else
 	IndexAmRoutine *amroutine = makeNode(IndexAmRoutine);

 	amroutine->amstrategies = 0;
@@ -249,11 +182,6 @@ ivfflathandler(PG_FUNCTION_ARGS)
 	amroutine->amoptsprocnum = 0;
 	amroutine->amcanorder = false;
 	amroutine->amcanorderbyop = true;
-#if PG_VERSION_NUM >= 180000
-	amroutine->amcanhash = false;
-	amroutine->amconsistentequality = false;
-	amroutine->amconsistentordering = false;
-#endif
 	amroutine->amcanbackward = false;	/* can change direction mid-scan */
 	amroutine->amcanunique = false;
 	amroutine->amcanmulticol = false;
@@ -286,9 +214,6 @@ ivfflathandler(PG_FUNCTION_ARGS)
 	amroutine->amvacuumcleanup = ivfflatvacuumcleanup;
 	amroutine->amcanreturn = NULL;	/* tuple not included in heapsort */
 	amroutine->amcostestimate = ivfflatcostestimate;
-#if PG_VERSION_NUM >= 180000
-	amroutine->amgettreeheight = NULL;
-#endif
 	amroutine->amoptions = ivfflatoptions;
 	amroutine->amproperty = NULL;	/* TODO AMPROP_DISTANCE_ORDERABLE */
 	amroutine->ambuildphasename = ivfflatbuildphasename;
@@ -309,11 +234,5 @@ ivfflathandler(PG_FUNCTION_ARGS)
 	amroutine->aminitparallelscan = NULL;
 	amroutine->amparallelrescan = NULL;

-#if PG_VERSION_NUM >= 180000
-	amroutine->amtranslatestrategy = NULL;
-	amroutine->amtranslatecmptype = NULL;
-#endif
-
 	PG_RETURN_POINTER(amroutine);
-#endif
 }
--- a/src/ivfflat.h
+++ b/src/ivfflat.h
@@ -9,15 +9,10 @@
 #include "lib/pairingheap.h"
 #include "nodes/execnodes.h"
 #include "port.h"				/* for random() */
-#include "storage/condition_variable.h"
 #include "utils/sampling.h"
 #include "utils/tuplesort.h"
 #include "vector.h"

-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
-
 #if PG_VERSION_NUM >= 150000
 #include "common/pg_prng.h"
 #endif
@@ -26,10 +21,6 @@
 #include "portability/instr_time.h"
 #endif

-#if PG_VERSION_NUM >= 190000
-typedef Pointer Item;
-#endif
-
 #define IVFFLAT_MAX_DIM 2000

 /* Support functions */
@@ -82,23 +73,21 @@ typedef Pointer Item;
 #if PG_VERSION_NUM >= 150000
 #define RandomDouble() pg_prng_double(&pg_global_prng_state)
 #define RandomInt() pg_prng_uint32(&pg_global_prng_state)
-#define SeedRandom(seed) pg_prng_seed(&pg_global_prng_state, seed)
 #else
 #define RandomDouble() (((double) random()) / MAX_RANDOM_VALUE)
 #define RandomInt() random()
-#define SeedRandom(seed) srandom(seed)
 #endif

 /* Variables */
 extern int	ivfflat_probes;
-extern int	ivfflat_iterative_scan;
+extern int	ivfflat_iterative_search;
 extern int	ivfflat_max_probes;

-typedef enum IvfflatIterativeScanMode
+typedef enum IvfflatIterativeSearchMode
 {
-	IVFFLAT_ITERATIVE_SCAN_OFF,
-	IVFFLAT_ITERATIVE_SCAN_RELAXED
-}			IvfflatIterativeScanMode;
+	IVFFLAT_ITERATIVE_SEARCH_OFF,
+	IVFFLAT_ITERATIVE_SEARCH_RELAXED
+}			IvfflatIterativeSearchMode;

 typedef struct VectorArrayData
 {
@@ -204,7 +193,6 @@ typedef struct IvfflatBuildState
 	VectorArray samples;
 	VectorArray centers;
 	ListInfo   *listInfo;
-	Size		itemsize;

 #ifdef IVFFLAT_KMEANS_DEBUG
 	double		inertia;
@@ -215,8 +203,7 @@ typedef struct IvfflatBuildState
 	/* Sampling */
 	BlockSamplerData bs;
 	ReservoirStateData rstate;
-	double		samplerows;
-	double		rowstoskip;
+	int			rowstoskip;

 	/* Sorting */
 	Tuplesortstate *sortstate;
@@ -224,7 +211,6 @@ typedef struct IvfflatBuildState
 	TupleTableSlot *slot;

 	/* Memory */
-	Size		memoryUsed;
 	MemoryContext tmpCtx;

 	/* Parallel builds */
@@ -305,32 +291,22 @@ typedef IvfflatScanOpaqueData * IvfflatScanOpaque;
 static inline Pointer
 VectorArrayGet(VectorArray arr, int offset)
 {
-	if (offset >= arr->maxlen)
-		elog(ERROR, "safety check failed");
-
 	return ((char *) arr->items) + (offset * arr->itemsize);
 }

 static inline void
 VectorArraySet(VectorArray arr, int offset, Pointer val)
 {
-	Size		size = VARSIZE_ANY(val);
-
-	if (size > arr->itemsize)
-		elog(ERROR, "safety check failed");
-
-	memcpy(VectorArrayGet(arr, offset), val, size);
+	memcpy(VectorArrayGet(arr, offset), val, VARSIZE_ANY(val));
 }

 /* Methods */
 VectorArray VectorArrayInit(int maxlen, int dimensions, Size itemsize);
 void		VectorArrayFree(VectorArray arr);
-void		IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo, Size memoryUsed);
+void		IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo);
 FmgrInfo   *IvfflatOptionalProcInfo(Relation index, uint16 procnum);
 Datum		IvfflatNormValue(const IvfflatTypeInfo * typeInfo, Oid collation, Datum value);
 bool		IvfflatCheckNorm(FmgrInfo *procinfo, Oid collation, Datum value);
-void		IvfflatNormVectors(const IvfflatTypeInfo * typeInfo, Oid collation, VectorArray arr, MemoryContext tmpCtx);
-void		IvfflatCheckMemoryUsage(Size totalSize);
 int			IvfflatGetLists(Relation index);
 void		IvfflatGetMetaPageInfo(Relation index, int *lists, int *dimensions);
 void		IvfflatUpdateList(Relation index, ListInfo listInfo, BlockNumber insertPage, BlockNumber originalInsertPage, BlockNumber startPage, ForkNumber forkNum);
--- a/src/ivfinsert.c
+++ b/src/ivfinsert.c
@@ -2,16 +2,11 @@

 #include <float.h>

-#include "access/genam.h"
 #include "access/generic_xlog.h"
-#include "access/itup.h"
-#include "fmgr.h"
 #include "ivfflat.h"
-#include "nodes/execnodes.h"
 #include "storage/bufmgr.h"
 #include "storage/lmgr.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"

 /*
 * Find the list that minimizes the distance function
@@ -70,7 +65,7 @@ FindInsertPage(Relation index, Datum *values, BlockNumber *insertPage, ListInfo
 * Insert a tuple into the index
 */
 static void
-InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid)
+InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid, Relation heapRel)
 {
 	const		IvfflatTypeInfo *typeInfo = IvfflatGetTypeInfo(index);
 	IndexTuple	itup;
@@ -209,7 +204,7 @@ ivfflatinsert(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid,
 	oldCtx = MemoryContextSwitchTo(insertCtx);

 	/* Insert tuple */
-	InsertTuple(index, values, isnull, heap_tid);
+	InsertTuple(index, values, isnull, heap_tid, heap);

 	/* Delete memory context */
 	MemoryContextSwitchTo(oldCtx);
--- a/src/ivfkmeans.c
+++ b/src/ivfkmeans.c
@@ -1,19 +1,17 @@
 #include "postgres.h"

 #include <float.h>
-#include <limits.h>
 #include <math.h>

-#include "access/genam.h"
-#include "fmgr.h"
+#include "bitvec.h"
+#include "halfutils.h"
+#include "halfvec.h"
 #include "ivfflat.h"
 #include "miscadmin.h"
+#include "utils/builtins.h"
+#include "utils/datum.h"
 #include "utils/memutils.h"
-#include "utils/relcache.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
+#include "vector.h"

 /*
 * Initialize with kmeans++
@@ -99,8 +97,22 @@ NormCenters(const IvfflatTypeInfo * typeInfo, Oid collation, VectorArray centers
 	MemoryContext normCtx = AllocSetContextCreate(CurrentMemoryContext,
 												  "Ivfflat norm temporary context",
 												  ALLOCSET_DEFAULT_SIZES);
+	MemoryContext oldCtx = MemoryContextSwitchTo(normCtx);

-	IvfflatNormVectors(typeInfo, collation, centers, normCtx);
+	for (int j = 0; j < centers->length; j++)
+	{
+		Datum		center = PointerGetDatum(VectorArrayGet(centers, j));
+		Datum		newCenter = IvfflatNormValue(typeInfo, collation, center);
+		Size		size = VARSIZE_ANY(DatumGetPointer(newCenter));
+
+		if (size > centers->itemsize)
+			elog(ERROR, "safety check failed");
+
+		memcpy(DatumGetPointer(center), DatumGetPointer(newCenter), size);
+		MemoryContextReset(normCtx);
+	}
+
+	MemoryContextSwitchTo(oldCtx);
 	MemoryContextDelete(normCtx);
 }

@@ -244,7 +256,7 @@ ComputeNewCenters(VectorArray samples, float *agg, VectorArray newCenters, int *
 * https://www.aaai.org/Papers/ICML/2003/ICML03-022.pdf
 */
 static void
-ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo, Size memoryUsed)
+ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo)
 {
 	FmgrInfo   *procinfo;
 	FmgrInfo   *normprocinfo;
@@ -263,6 +275,8 @@ ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, const Ivff
 	float	   *newcdist;

 	/* Calculate allocation sizes */
+	Size		samplesSize = VECTOR_ARRAY_SIZE(samples->maxlen, samples->itemsize);
+	Size		centersSize = VECTOR_ARRAY_SIZE(centers->maxlen, centers->itemsize);
 	Size		newCentersSize = VECTOR_ARRAY_SIZE(numCenters, centers->itemsize);
 	Size		aggSize = sizeof(float) * (int64) numCenters * dimensions;
 	Size		centerCountsSize = sizeof(int) * numCenters;
@@ -274,13 +288,18 @@ ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, const Ivff
 	Size		newcdistSize = sizeof(float) * numCenters;

 	/* Calculate total size */
-	Size		totalSize = memoryUsed + newCentersSize + aggSize + centerCountsSize + closestCentersSize + lowerBoundSize + upperBoundSize + sSize + halfcdistSize + newcdistSize;
+	Size		totalSize = samplesSize + centersSize + newCentersSize + aggSize + centerCountsSize + closestCentersSize + lowerBoundSize + upperBoundSize + sSize + halfcdistSize + newcdistSize;

 	/* Check memory requirements */
-	IvfflatCheckMemoryUsage(totalSize);
+	/* Add one to error message to ceil */
+	if (totalSize > (Size) maintenance_work_mem * 1024L)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("memory required is %zu MB, maintenance_work_mem is %d MB",
+						totalSize / (1024 * 1024) + 1, maintenance_work_mem / 1024)));

 	/* Ensure indexing does not overflow */
-	if (numCenters > INT_MAX / numCenters)
+	if (numCenters * numCenters > INT_MAX)
 		elog(ERROR, "Indexing overflow detected. Please report a bug.");

 	/* Set support functions */
@@ -541,7 +560,7 @@ CheckCenters(Relation index, VectorArray centers, const IvfflatTypeInfo * typeIn
 * We use spherical k-means for inner product and cosine
 */
 void
-IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo, Size memoryUsed)
+IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers, const IvfflatTypeInfo * typeInfo)
 {
 	MemoryContext kmeansCtx = AllocSetContextCreate(CurrentMemoryContext,
 													"Ivfflat kmeans temporary context",
@@ -551,7 +570,7 @@ IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers, const Iv
 	if (samples->length == 0)
 		RandomCenters(index, centers, typeInfo);
 	else
-		ElkanKmeans(index, samples, centers, typeInfo, memoryUsed);
+		ElkanKmeans(index, samples, centers, typeInfo);

 	CheckCenters(index, centers, typeInfo);

--- a/src/ivfscan.c
+++ b/src/ivfscan.c
@@ -2,26 +2,15 @@

 #include <float.h>

-#include "access/genam.h"
-#include "access/itup.h"
 #include "access/relscan.h"
-#include "access/tupdesc.h"
 #include "catalog/pg_operator_d.h"
 #include "catalog/pg_type_d.h"
-#include "fmgr.h"
 #include "lib/pairingheap.h"
 #include "ivfflat.h"
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "storage/bufmgr.h"
 #include "utils/memutils.h"
-#include "utils/rel.h"
-#include "utils/snapmgr.h"
-#include "utils/tuplesort.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 #define GetScanList(ptr) pairingheap_container(IvfflatScanList, ph_node, ptr)
 #define GetScanListConst(ptr) pairingheap_const_container(IvfflatScanList, ph_node, ptr)
@@ -125,6 +114,7 @@ GetScanItems(IndexScanDesc scan, Datum value)
 {
 	IvfflatScanOpaque so = (IvfflatScanOpaque) scan->opaque;
 	TupleDesc	tupdesc = RelationGetDescr(scan->indexRelation);
+	double		tuples = 0;
 	TupleTableSlot *slot = so->vslot;
 	int			batchProbes = 0;

@@ -171,6 +161,8 @@ GetScanItems(IndexScanDesc scan, Datum value)
 				ExecStoreVirtualTuple(slot);

 				tuplesort_puttupleslot(so->sortstate, slot);
+
+				tuples++;
 			}

 			searchPage = IvfflatPageGetOpaque(page)->nextblkno;
@@ -179,6 +171,12 @@ GetScanItems(IndexScanDesc scan, Datum value)
 		}
 	}

+	if (tuples < 100 && ivfflat_iterative_search == IVFFLAT_ITERATIVE_SEARCH_OFF)
+		ereport(DEBUG1,
+				(errmsg("index scan found few tuples"),
+				 errdetail("Index may have been created with little data."),
+				 errhint("Recreate the index and possibly decrease lists.")));
+
 	tuplesort_performsort(so->sortstate);

 #if defined(IVFFLAT_MEMORY)
@@ -265,8 +263,18 @@ ivfflatbeginscan(Relation index, int nkeys, int norderbys)
 	/* Get lists and dimensions from metapage */
 	IvfflatGetMetaPageInfo(index, &lists, &dimensions);

-	if (ivfflat_iterative_scan != IVFFLAT_ITERATIVE_SCAN_OFF)
-		maxProbes = Max(ivfflat_max_probes, probes);
+	if (ivfflat_iterative_search != IVFFLAT_ITERATIVE_SEARCH_OFF)
+	{
+		maxProbes = ivfflat_max_probes;
+
+		if (maxProbes < 0)
+			maxProbes = lists;
+		else if (maxProbes < probes)
+		{
+			/* TODO Show notice */
+			maxProbes = probes;
+		}
+	}
 	else
 		maxProbes = probes;

@@ -298,9 +306,6 @@ ivfflatbeginscan(Relation index, int nkeys, int norderbys)
 	so->tupdesc = CreateTemplateTupleDesc(2);
 	TupleDescInitEntry(so->tupdesc, (AttrNumber) 1, "distance", FLOAT8OID, -1, 0);
 	TupleDescInitEntry(so->tupdesc, (AttrNumber) 2, "heaptid", TIDOID, -1, 0);
-#if PG_VERSION_NUM >= 190000
-	TupleDescFinalize(so->tupdesc);
-#endif

 	/* Prep sort */
 	so->sortstate = InitScanSortState(so->tupdesc);
@@ -369,10 +374,6 @@ ivfflatgettuple(IndexScanDesc scan, ScanDirection dir)

 		/* Count index scan for stats */
 		pgstat_count_index_scan(scan->indexRelation);
-#if PG_VERSION_NUM >= 180000
-		if (scan->instrument)
-			scan->instrument->nsearches++;
-#endif

 		/* Safety check */
 		if (scan->orderByData == NULL)
--- a/src/ivfutils.c
+++ b/src/ivfutils.c
@@ -1,21 +1,13 @@
 #include "postgres.h"

-#include "access/genam.h"
 #include "access/generic_xlog.h"
+#include "bitvec.h"
+#include "catalog/pg_type.h"
 #include "fmgr.h"
 #include "halfutils.h"
 #include "halfvec.h"
 #include "ivfflat.h"
-#include "miscadmin.h"
 #include "storage/bufmgr.h"
-#include "utils/memutils.h"
-#include "utils/relcache.h"
-#include "utils/varbit.h"
-#include "vector.h"
-
-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif

 /*
 * Allocate a vector array
@@ -90,40 +82,6 @@ IvfflatCheckNorm(FmgrInfo *procinfo, Oid collation, Datum value)
 	return DatumGetFloat8(FunctionCall1Coll(procinfo, collation, value)) > 0;
 }

-/*
- * Normalize vectors
- */
-void
-IvfflatNormVectors(const IvfflatTypeInfo * typeInfo, Oid collation, VectorArray arr, MemoryContext tmpCtx)
-{
-	MemoryContext oldCtx = MemoryContextSwitchTo(tmpCtx);
-
-	for (int i = 0; i < arr->length; i++)
-	{
-		Datum		value = PointerGetDatum(VectorArrayGet(arr, i));
-		Datum		newValue = IvfflatNormValue(typeInfo, collation, value);
-
-		VectorArraySet(arr, i, DatumGetPointer(newValue));
-		MemoryContextReset(tmpCtx);
-	}
-
-	MemoryContextSwitchTo(oldCtx);
-}
-
-/*
- * Check memory usage
- */
-void
-IvfflatCheckMemoryUsage(Size totalSize)
-{
-	/* Add one to error message to ceil */
-	if (totalSize > maintenance_work_mem * (Size) 1024)
-		ereport(ERROR,
-				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-				 errmsg("memory required is %zu MB, maintenance_work_mem is %d MB",
-						totalSize / (1024 * 1024) + 1, maintenance_work_mem / 1024)));
-}
-
 /*
 * New buffer
 */
@@ -301,8 +259,8 @@ VectorUpdateCenter(Pointer v, int dimensions, float *x)
 	SET_VARSIZE(vec, VECTOR_SIZE(dimensions));
 	vec->dim = dimensions;

-	for (int i = 0; i < dimensions; i++)
-		vec->x[i] = x[i];
+	for (int k = 0; k < dimensions; k++)
+		vec->x[k] = x[k];
 }

 static void
@@ -313,8 +271,8 @@ HalfvecUpdateCenter(Pointer v, int dimensions, float *x)
 	SET_VARSIZE(vec, HALFVEC_SIZE(dimensions));
 	vec->dim = dimensions;

-	for (int i = 0; i < dimensions; i++)
-		vec->x[i] = Float4ToHalfUnchecked(x[i]);
+	for (int k = 0; k < dimensions; k++)
+		vec->x[k] = Float4ToHalfUnchecked(x[k]);
 }

 static void
@@ -326,33 +284,29 @@ BitUpdateCenter(Pointer v, int dimensions, float *x)
 	SET_VARSIZE(vec, VARBITTOTALLEN(dimensions));
 	VARBITLEN(vec) = dimensions;

-	for (uint32 i = 0; i < VARBITBYTES(vec); i++)
-		nx[i] = 0;
+	for (uint32 k = 0; k < VARBITBYTES(vec); k++)
+		nx[k] = 0;

-	for (int i = 0; i < dimensions; i++)
-		nx[i / 8] |= (x[i] > 0.5 ? 1 : 0) << (7 - (i % 8));
+	for (int k = 0; k < dimensions; k++)
+		nx[k / 8] |= (x[k] > 0.5 ? 1 : 0) << (7 - (k % 8));
 }

 static void
 VectorSumCenter(Pointer v, float *x)
 {
 	Vector	   *vec = (Vector *) v;
-	int			dim = vec->dim;

-	/* Auto-vectorized */
-	for (int i = 0; i < dim; i++)
-		x[i] += vec->x[i];
+	for (int k = 0; k < vec->dim; k++)
+		x[k] += vec->x[k];
 }

 static void
 HalfvecSumCenter(Pointer v, float *x)
 {
 	HalfVector *vec = (HalfVector *) v;
-	int			dim = vec->dim;

-	/* Auto-vectorized on aarch64 */
-	for (int i = 0; i < dim; i++)
-		x[i] += HalfToFloat4(vec->x[i]);
+	for (int k = 0; k < vec->dim; k++)
+		x[k] += HalfToFloat4(vec->x[k]);
 }

 static void
@@ -360,8 +314,8 @@ BitSumCenter(Pointer v, float *x)
 {
 	VarBit	   *vec = (VarBit *) v;

-	for (int i = 0; i < VARBITLEN(vec); i++)
-		x[i] += (float) (((VARBITS(vec)[i / 8]) >> (7 - (i % 8))) & 0x01);
+	for (int k = 0; k < VARBITLEN(vec); k++)
+		x[k] += (float) (((VARBITS(vec)[k / 8]) >> (7 - (k % 8))) & 0x01);
 }

 /*
@@ -401,7 +355,7 @@ ivfflat_halfvec_support(PG_FUNCTION_ARGS)
 	};

 	PG_RETURN_POINTER(&typeInfo);
-}
+};

 FUNCTION_PREFIX PG_FUNCTION_INFO_V1(ivfflat_bit_support);
 Datum
@@ -416,4 +370,4 @@ ivfflat_bit_support(PG_FUNCTION_ARGS)
 	};

 	PG_RETURN_POINTER(&typeInfo);
-}
+};
--- a/src/ivfvacuum.c
+++ b/src/ivfvacuum.c
@@ -1,16 +1,9 @@
 #include "postgres.h"

-#include "access/genam.h"
 #include "access/generic_xlog.h"
-#include "access/itup.h"
 #include "commands/vacuum.h"
 #include "ivfflat.h"
 #include "storage/bufmgr.h"
-#include "utils/relcache.h"
-
-#if PG_VERSION_NUM >= 180000
-#define vacuum_delay_point() vacuum_delay_point(false)
-#endif

 /*
 * Bulk delete tuples from the index
--- a/src/sparsevec.c
+++ b/src/sparsevec.c
@@ -4,26 +4,23 @@
 #include <math.h>

 #include "catalog/pg_type.h"
-#include "common/shortest_dec.h"
+#include "common/string.h"
 #include "fmgr.h"
 #include "halfutils.h"
 #include "halfvec.h"
-#include "lib/stringinfo.h"
 #include "libpq/pqformat.h"
 #include "sparsevec.h"
 #include "utils/array.h"
 #include "utils/builtins.h"
-#include "utils/float.h"
-#include "utils/fmgrprotos.h"
 #include "utils/lsyscache.h"
 #include "vector.h"

-#if PG_VERSION_NUM >= 160000
-#include "varatt.h"
-#endif
-
-#if PG_VERSION_NUM >= 170000
-#include "parser/scansup.h"
+#if PG_VERSION_NUM >= 120000
+#include "common/shortest_dec.h"
+#include "utils/float.h"
+#else
+#include <float.h>
+#include "utils/builtins.h"
 #endif

 typedef struct SparseInputElement
@@ -159,9 +156,9 @@ InitSparseVector(int dim, int nnz)
 	return result;
 }

-#if PG_VERSION_NUM >= 170000
-#define sparsevec_isspace(ch) scanner_isspace(ch)
-#else
+/*
+ * Check for whitespace, since array_isspace() is static
+ */
 static inline bool
 sparsevec_isspace(char ch)
 {
@@ -174,7 +171,6 @@ sparsevec_isspace(char ch)
 		return true;
 	return false;
 }
-#endif

 /*
 * Compare indices
@@ -182,10 +178,10 @@ sparsevec_isspace(char ch)
 static int
 CompareIndices(const void *a, const void *b)
 {
-	if (((const SparseInputElement *) a)->index < ((const SparseInputElement *) b)->index)
+	if (((SparseInputElement *) a)->index < ((SparseInputElement *) b)->index)
 		return -1;

-	if (((const SparseInputElement *) a)->index > ((const SparseInputElement *) b)->index)
+	if (((SparseInputElement *) a)->index > ((SparseInputElement *) b)->index)
 		return 1;

 	return 0;
--- a/src/vector.c
+++ b/src/vector.c
@@ -16,20 +16,16 @@
 #include "port.h"				/* for strtof() */
 #include "sparsevec.h"
 #include "utils/array.h"
+#include "utils/builtins.h"
 #include "utils/float.h"
-#include "utils/fmgrprotos.h"
 #include "utils/lsyscache.h"
-#include "utils/varbit.h"
+#include "utils/numeric.h"
 #include "vector.h"

 #if PG_VERSION_NUM >= 160000
 #include "varatt.h"
 #endif

-#if PG_VERSION_NUM >= 170000
-#include "parser/scansup.h"
-#endif
-
 #define STATE_DIMS(x) (ARR_DIMS(x)[0] - 1)
 #define CreateStateDatums(dim) palloc(sizeof(Datum) * (dim + 1))

@@ -39,11 +35,7 @@
 #define VECTOR_TARGET_CLONES
 #endif

-#if PG_VERSION_NUM >= 180000
-PG_MODULE_MAGIC_EXT(.name = "vector", .version = "0.8.4");
-#else
 PG_MODULE_MAGIC;
-#endif

 /*
 * Initialize index options and variables
@@ -133,9 +125,9 @@ InitVector(int dim)
 	return result;
 }

-#if PG_VERSION_NUM >= 170000
-#define vector_isspace(ch) scanner_isspace(ch)
-#else
+/*
+ * Check for whitespace, since array_isspace() is static
+ */
 static inline bool
 vector_isspace(char ch)
 {
@@ -148,7 +140,6 @@ vector_isspace(char ch)
 		return true;
 	return false;
 }
-#endif

 /*
 * Check state array
@@ -929,13 +920,11 @@ vector_concat(PG_FUNCTION_ARGS)
 	CheckDim(dim);
 	result = InitVector(dim);

-	/* Auto-vectorized */
-	for (int i = 0, imax = a->dim; i < imax; i++)
+	for (int i = 0; i < a->dim; i++)
 		result->x[i] = a->x[i];

-	/* Auto-vectorized */
-	for (int i = 0, imax = b->dim, start = a->dim; i < imax; i++)
-		result->x[i + start] = b->x[i];
+	for (int i = 0; i < b->dim; i++)
+		result->x[i + a->dim] = b->x[i];

 	PG_RETURN_POINTER(result);
 }
@@ -951,21 +940,8 @@ binary_quantize(PG_FUNCTION_ARGS)
 	float	   *ax = a->x;
 	VarBit	   *result = InitBitVector(a->dim);
 	unsigned char *rx = VARBITS(result);
-	int			i = 0;
-	int			count = (a->dim / 8) * 8;

-	/* Auto-vectorized */
-	for (; i < count; i += 8)
-	{
-		unsigned char result_byte = 0;
-
-		for (int j = 0; j < 8; j++)
-			result_byte |= (ax[i + j] > 0) << (7 - j);
-
-		rx[i / 8] = result_byte;
-	}
-
-	for (; i < a->dim; i++)
+	for (int i = 0; i < a->dim; i++)
 		rx[i / 8] |= (ax[i] > 0) << (7 - (i % 8));

 	PG_RETURN_VARBIT_P(result);
--- a/test/expected/cast.out
+++ b/test/expected/cast.out
@@ -140,6 +140,34 @@ SELECT '{1e-8,-1e-8}'::real[]::halfvec;
 [0,-0]
 (1 row)

+SELECT '[1,2,3]'::intvec::integer[];
+  int4   
+---------
+ {1,2,3}
+(1 row)
+
+SELECT '{1,2,3}'::integer[]::intvec;
+ intvec  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT '{1,2,3}'::integer[]::intvec(3);
+ intvec  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT '{1,2,3}'::integer[]::intvec(2);
+ERROR:  expected 2 dimensions, not 3
+SELECT '{127,-128}'::integer[]::intvec;
+   intvec   
+------------
+ [127,-128]
+(1 row)
+
+SELECT '{128,-129}'::integer[]::intvec;
+ERROR:  value "128" is out of range for type intvec
 SELECT '[0,1.5,0,3.5,0]'::vector::sparsevec;
    sparsevec    
 -----------------
--- a/test/expected/copy.out
+++ b/test/expected/copy.out
@@ -30,6 +30,23 @@ SELECT * FROM t2 ORDER BY val;
 
 (4 rows)

+DROP TABLE t;
+DROP TABLE t2;
+-- intvec
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE TABLE t2 (val intvec(3));
+\copy t TO 'results/intvec.bin' WITH (FORMAT binary)
+\copy t2 FROM 'results/intvec.bin' WITH (FORMAT binary)
+SELECT * FROM t2 ORDER BY val;
+   val   
+---------
+ [0,0,0]
+ [1,1,1]
+ [1,2,3]
+ 
+(4 rows)
+
 DROP TABLE t;
 DROP TABLE t2;
 -- sparsevec
--- a/test/expected/halfvec.out
+++ b/test/expected/halfvec.out
@@ -540,12 +540,6 @@ SELECT binary_quantize('[0,0.1,-0.2,-0.3,0.4,0.5,0.6,-0.7,0.8,-0.9,1]'::halfvec)
 01001110101
 (1 row)

-SELECT binary_quantize('[1,2,3,-4,5,6,-7,8,1,-2,-3,4,5,-6,7,8,-1,2,3]'::halfvec);
-   binary_quantize   
---------------------
- 1110110110011011011
-(1 row)
-
 SELECT subvector('[1,2,3,4,5]'::halfvec, 1, 3);
 subvector 
 -----------
--- a/test/expected/hnsw_intvec.out
+++ b/test/expected/hnsw_intvec.out
@@ -0,0 +1,102 @@
+SET enable_seqscan = off;
+-- L2
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_l2_ops);
+INSERT INTO t (val) VALUES ('[1,2,4]');
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+   val   
+---------
+ [1,2,3]
+ [1,2,4]
+ [1,1,1]
+ [0,0,0]
+(4 rows)
+
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <-> (SELECT NULL::intvec)) t2;
+ count 
+-------
+     4
+(1 row)
+
+SELECT COUNT(*) FROM t;
+ count 
+-------
+     5
+(1 row)
+
+TRUNCATE t;
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+ val 
+-----
+(0 rows)
+
+DROP TABLE t;
+-- inner product
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_ip_ops);
+INSERT INTO t (val) VALUES ('[1,2,4]');
+SELECT * FROM t ORDER BY val <#> '[3,3,3]';
+   val   
+---------
+ [1,2,4]
+ [1,2,3]
+ [1,1,1]
+ [0,0,0]
+(4 rows)
+
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <#> (SELECT NULL::intvec)) t2;
+ count 
+-------
+     4
+(1 row)
+
+DROP TABLE t;
+-- cosine
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_cosine_ops);
+INSERT INTO t (val) VALUES ('[1,2,4]');
+SELECT * FROM t ORDER BY val <=> '[3,3,3]';
+   val   
+---------
+ [1,1,1]
+ [1,2,3]
+ [1,2,4]
+(3 rows)
+
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> '[0,0,0]') t2;
+ count 
+-------
+     3
+(1 row)
+
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> (SELECT NULL::intvec)) t2;
+ count 
+-------
+     3
+(1 row)
+
+DROP TABLE t;
+-- L1
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_l1_ops);
+INSERT INTO t (val) VALUES ('[1,2,4]');
+SELECT * FROM t ORDER BY val <+> '[3,3,3]';
+   val   
+---------
+ [1,2,3]
+ [1,2,4]
+ [1,1,1]
+ [0,0,0]
+(4 rows)
+
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <+> (SELECT NULL::intvec)) t2;
+ count 
+-------
+     4
+(1 row)
+
+DROP TABLE t;
--- a/test/expected/hnsw_vector.out
+++ b/test/expected/hnsw_vector.out
@@ -104,7 +104,7 @@ DROP TABLE t;
 CREATE TABLE t (val vector(3));
 INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
 CREATE INDEX ON t USING hnsw (val vector_l2_ops);
-SET hnsw.iterative_scan = strict_order;
+SET hnsw.iterative_search = strict_order;
 SET hnsw.ef_search = 1;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';
   val   
@@ -114,7 +114,7 @@ SELECT * FROM t ORDER BY val <-> '[3,3,3]';
 [0,0,0]
 (3 rows)

-SET hnsw.iterative_scan = relaxed_order;
+SET hnsw.iterative_search = relaxed_order;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';
   val   
 ---------
@@ -123,13 +123,7 @@ SELECT * FROM t ORDER BY val <-> '[3,3,3]';
 [0,0,0]
 (3 rows)

-TRUNCATE t;
-SELECT * FROM t ORDER BY val <-> '[3,3,3]';
- val 
-----
-(0 rows)
-
-RESET hnsw.iterative_scan;
+RESET hnsw.iterative_search;
 RESET hnsw.ef_search;
 DROP TABLE t;
 -- unlogged
@@ -171,31 +165,21 @@ SET hnsw.ef_search = 0;
 ERROR:  0 is outside the valid range for parameter "hnsw.ef_search" (1 .. 1000)
 SET hnsw.ef_search = 1001;
 ERROR:  1001 is outside the valid range for parameter "hnsw.ef_search" (1 .. 1000)
-SHOW hnsw.iterative_scan;
- hnsw.iterative_scan 
---------------------
+SHOW hnsw.iterative_search;
+ hnsw.iterative_search 
+-----------------------
 off
 (1 row)

-SET hnsw.iterative_scan = on;
-ERROR:  invalid value for parameter "hnsw.iterative_scan": "on"
+SET hnsw.iterative_search = on;
+ERROR:  invalid value for parameter "hnsw.iterative_search": "on"
 HINT:  Available values: off, relaxed_order, strict_order.
-SHOW hnsw.max_scan_tuples;
- hnsw.max_scan_tuples 
----------------------
- 20000
+SHOW hnsw.max_search_tuples;
+ hnsw.max_search_tuples 
+------------------------
+ -1
 (1 row)

-SET hnsw.max_scan_tuples = 0;
-ERROR:  0 is outside the valid range for parameter "hnsw.max_scan_tuples" (1 .. 2147483647)
-SHOW hnsw.scan_mem_multiplier;
- hnsw.scan_mem_multiplier 
--------------------------
- 1
-(1 row)
-
-SET hnsw.scan_mem_multiplier = 0;
-ERROR:  0 is outside the valid range for parameter "hnsw.scan_mem_multiplier" (1 .. 1000)
-SET hnsw.scan_mem_multiplier = 1001;
-ERROR:  1001 is outside the valid range for parameter "hnsw.scan_mem_multiplier" (1 .. 1000)
+SET hnsw.max_search_tuples = -2;
+ERROR:  -2 is outside the valid range for parameter "hnsw.max_search_tuples" (-1 .. 2147483647)
 DROP TABLE t;
--- a/test/expected/intvec.out
+++ b/test/expected/intvec.out
@@ -0,0 +1,328 @@
+SELECT '[1,2,3]'::intvec;
+ intvec  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT '[-1,-2,-3]'::intvec;
+   intvec   
+------------
+ [-1,-2,-3]
+(1 row)
+
+SELECT ' [ 1,  2 ,    3  ] '::intvec;
+ intvec  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT '[1.23456]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1.23456]"
+LINE 1: SELECT '[1.23456]'::intvec;
+               ^
+SELECT '[hello,1]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[hello,1]"
+LINE 1: SELECT '[hello,1]'::intvec;
+               ^
+SELECT '[127,-128]'::intvec;
+   intvec   
+------------
+ [127,-128]
+(1 row)
+
+SELECT '[128,-129]'::intvec;
+ERROR:  "128" is out of range for type intvec
+LINE 1: SELECT '[128,-129]'::intvec;
+               ^
+SELECT '[1,2,3'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1,2,3"
+LINE 1: SELECT '[1,2,3'::intvec;
+               ^
+SELECT '[1,2,3]9'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1,2,3]9"
+LINE 1: SELECT '[1,2,3]9'::intvec;
+               ^
+DETAIL:  Junk after closing right brace.
+SELECT '1,2,3'::intvec;
+ERROR:  invalid input syntax for type intvec: "1,2,3"
+LINE 1: SELECT '1,2,3'::intvec;
+               ^
+DETAIL:  Vector contents must start with "[".
+SELECT ''::intvec;
+ERROR:  invalid input syntax for type intvec: ""
+LINE 1: SELECT ''::intvec;
+               ^
+DETAIL:  Vector contents must start with "[".
+SELECT '['::intvec;
+ERROR:  invalid input syntax for type intvec: "["
+LINE 1: SELECT '['::intvec;
+               ^
+SELECT '[,'::intvec;
+ERROR:  invalid input syntax for type intvec: "[,"
+LINE 1: SELECT '[,'::intvec;
+               ^
+SELECT '[]'::intvec;
+ERROR:  intvec must have at least 1 dimension
+LINE 1: SELECT '[]'::intvec;
+               ^
+SELECT '[1,]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1,]"
+LINE 1: SELECT '[1,]'::intvec;
+               ^
+SELECT '[1a]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1a]"
+LINE 1: SELECT '[1a]'::intvec;
+               ^
+SELECT '[1,,3]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1,,3]"
+LINE 1: SELECT '[1,,3]'::intvec;
+               ^
+SELECT '[1, ,3]'::intvec;
+ERROR:  invalid input syntax for type intvec: "[1, ,3]"
+LINE 1: SELECT '[1, ,3]'::intvec;
+               ^
+SELECT '[1,2,3]'::intvec(3);
+ intvec  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT '[1,2,3]'::intvec(2);
+ERROR:  expected 2 dimensions, not 3
+SELECT '[1,2,3]'::intvec(3, 2);
+ERROR:  invalid type modifier
+LINE 1: SELECT '[1,2,3]'::intvec(3, 2);
+                          ^
+SELECT '[1,2,3]'::intvec('a');
+ERROR:  invalid input syntax for type integer: "a"
+LINE 1: SELECT '[1,2,3]'::intvec('a');
+                          ^
+SELECT '[1,2,3]'::intvec(0);
+ERROR:  dimensions for type intvec must be at least 1
+LINE 1: SELECT '[1,2,3]'::intvec(0);
+                          ^
+SELECT '[1,2,3]'::intvec(16001);
+ERROR:  dimensions for type intvec cannot exceed 16000
+LINE 1: SELECT '[1,2,3]'::intvec(16001);
+                          ^
+SELECT unnest('{"[1,2,3]", "[4,5,6]"}'::intvec[]);
+ unnest  
+---------
+ [1,2,3]
+ [4,5,6]
+(2 rows)
+
+SELECT '{"[1,2,3]"}'::intvec(2)[];
+ERROR:  expected 2 dimensions, not 3
+SELECT '[1,2,3]'::intvec < '[1,2,3]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec < '[1,2]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec <= '[1,2,3]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,3]'::intvec <= '[1,2]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec = '[1,2,3]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,3]'::intvec = '[1,2]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec != '[1,2,3]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec != '[1,2]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,3]'::intvec >= '[1,2,3]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,3]'::intvec >= '[1,2]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,3]'::intvec > '[1,2,3]';
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT '[1,2,3]'::intvec > '[1,2]';
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT intvec_cmp('[1,2,3]', '[1,2,3]');
+ intvec_cmp 
+------------
+          0
+(1 row)
+
+SELECT intvec_cmp('[1,2,3]', '[0,0,0]');
+ intvec_cmp 
+------------
+          1
+(1 row)
+
+SELECT intvec_cmp('[0,0,0]', '[1,2,3]');
+ intvec_cmp 
+------------
+         -1
+(1 row)
+
+SELECT intvec_cmp('[1,2]', '[1,2,3]');
+ intvec_cmp 
+------------
+         -1
+(1 row)
+
+SELECT intvec_cmp('[1,2,3]', '[1,2]');
+ intvec_cmp 
+------------
+          1
+(1 row)
+
+SELECT intvec_cmp('[1,2]', '[2,3,4]');
+ intvec_cmp 
+------------
+         -1
+(1 row)
+
+SELECT intvec_cmp('[2,3]', '[1,2,3]');
+ intvec_cmp 
+------------
+          1
+(1 row)
+
+SELECT vector_dims('[1,2,3]'::intvec);
+ vector_dims 
+-------------
+           3
+(1 row)
+
+SELECT l2_distance('[0,0]'::intvec, '[3,4]');
+ l2_distance 
+-------------
+           5
+(1 row)
+
+SELECT l2_distance('[0,0]'::intvec, '[0,1]');
+ l2_distance 
+-------------
+           1
+(1 row)
+
+SELECT l2_distance('[1,2]'::intvec, '[3]');
+ERROR:  different intvec dimensions 2 and 1
+SELECT '[0,0]'::intvec <-> '[3,4]';
+ ?column? 
+----------
+        5
+(1 row)
+
+SELECT inner_product('[1,2]'::intvec, '[3,4]');
+ inner_product 
+---------------
+            11
+(1 row)
+
+SELECT inner_product('[1,2]'::intvec, '[3]');
+ERROR:  different intvec dimensions 2 and 1
+SELECT inner_product('[127]'::intvec, '[127]');
+ inner_product 
+---------------
+         16129
+(1 row)
+
+SELECT '[1,2]'::intvec <#> '[3,4]';
+ ?column? 
+----------
+      -11
+(1 row)
+
+SELECT cosine_distance('[1,2]'::intvec, '[2,4]');
+ cosine_distance 
+-----------------
+               0
+(1 row)
+
+SELECT cosine_distance('[1,2]'::intvec, '[0,0]');
+ cosine_distance 
+-----------------
+             NaN
+(1 row)
+
+SELECT cosine_distance('[1,1]'::intvec, '[1,1]');
+ cosine_distance 
+-----------------
+               0
+(1 row)
+
+SELECT cosine_distance('[1,0]'::intvec, '[0,2]');
+ cosine_distance 
+-----------------
+               1
+(1 row)
+
+SELECT cosine_distance('[1,1]'::intvec, '[-1,-1]');
+ cosine_distance 
+-----------------
+               2
+(1 row)
+
+SELECT cosine_distance('[1,2]'::intvec, '[3]');
+ERROR:  different intvec dimensions 2 and 1
+SELECT '[1,2]'::intvec <=> '[2,4]';
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT l1_distance('[0,0]'::intvec, '[3,4]');
+ l1_distance 
+-------------
+           7
+(1 row)
+
+SELECT l1_distance('[0,0]'::intvec, '[0,1]');
+ l1_distance 
+-------------
+           1
+(1 row)
+
+SELECT l1_distance('[1,2]'::intvec, '[3]');
+ERROR:  different intvec dimensions 2 and 1
--- a/test/expected/ivfflat_vector.out
+++ b/test/expected/ivfflat_vector.out
@@ -86,7 +86,7 @@ DROP TABLE t;
 CREATE TABLE t (val vector(3));
 INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
 CREATE INDEX ON t USING ivfflat (val vector_l2_ops) WITH (lists = 3);
-SET ivfflat.iterative_scan = relaxed_order;
+SET ivfflat.iterative_search = relaxed_order;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';
   val   
 ---------
@@ -95,6 +95,13 @@ SELECT * FROM t ORDER BY val <-> '[3,3,3]';
 [0,0,0]
 (3 rows)

+SET ivfflat.max_probes = 0;
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+   val   
+---------
+ [1,2,3]
+(1 row)
+
 SET ivfflat.max_probes = 1;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';
   val   
@@ -110,16 +117,7 @@ SELECT * FROM t ORDER BY val <-> '[3,3,3]';
 [1,1,1]
 (2 rows)

-TRUNCATE t;
-NOTICE:  ivfflat index created with little data
-DETAIL:  This will cause low recall.
-HINT:  Drop the index until the table has more data.
-SELECT * FROM t ORDER BY val <-> '[3,3,3]';
- val 
-----
-(0 rows)
-
-RESET ivfflat.iterative_scan;
+RESET ivfflat.iterative_search;
 RESET ivfflat.max_probes;
 DROP TABLE t;
 -- unlogged
@@ -153,23 +151,23 @@ SET ivfflat.probes = 0;
 ERROR:  0 is outside the valid range for parameter "ivfflat.probes" (1 .. 32768)
 SET ivfflat.probes = 32769;
 ERROR:  32769 is outside the valid range for parameter "ivfflat.probes" (1 .. 32768)
-SHOW ivfflat.iterative_scan;
- ivfflat.iterative_scan 
------------------------
+SHOW ivfflat.iterative_search;
+ ivfflat.iterative_search 
+--------------------------
 off
 (1 row)

-SET ivfflat.iterative_scan = on;
-ERROR:  invalid value for parameter "ivfflat.iterative_scan": "on"
+SET ivfflat.iterative_search = on;
+ERROR:  invalid value for parameter "ivfflat.iterative_search": "on"
 HINT:  Available values: off, relaxed_order.
 SHOW ivfflat.max_probes;
 ivfflat.max_probes 
 --------------------
- 32768
+ -1
 (1 row)

-SET ivfflat.max_probes = 0;
-ERROR:  0 is outside the valid range for parameter "ivfflat.max_probes" (1 .. 32768)
+SET ivfflat.max_probes = -2;
+ERROR:  -2 is outside the valid range for parameter "ivfflat.max_probes" (-1 .. 32768)
 SET ivfflat.max_probes = 32769;
-ERROR:  32769 is outside the valid range for parameter "ivfflat.max_probes" (1 .. 32768)
+ERROR:  32769 is outside the valid range for parameter "ivfflat.max_probes" (-1 .. 32768)
 DROP TABLE t;
--- a/test/expected/vector_type.out
+++ b/test/expected/vector_type.out
@@ -576,12 +576,6 @@ SELECT binary_quantize('[0,0.1,-0.2,-0.3,0.4,0.5,0.6,-0.7,0.8,-0.9,1]'::vector);
 01001110101
 (1 row)

-SELECT binary_quantize('[1,2,3,-4,5,6,-7,8,1,-2,-3,4,5,-6,7,8,-1,2,3]'::vector);
-   binary_quantize   
---------------------
- 1110110110011011011
-(1 row)
-
 SELECT subvector('[1,2,3,4,5]'::vector, 1, 3);
 subvector 
 -----------
--- a/test/sql/cast.sql
+++ b/test/sql/cast.sql
@@ -38,6 +38,14 @@ SELECT '{1,2,3}'::real[]::halfvec(2);
 SELECT '{65520,-65520}'::real[]::halfvec;
 SELECT '{1e-8,-1e-8}'::real[]::halfvec;

+SELECT '[1,2,3]'::intvec::integer[];
+
+SELECT '{1,2,3}'::integer[]::intvec;
+SELECT '{1,2,3}'::integer[]::intvec(3);
+SELECT '{1,2,3}'::integer[]::intvec(2);
+SELECT '{127,-128}'::integer[]::intvec;
+SELECT '{128,-129}'::integer[]::intvec;
+
 SELECT '[0,1.5,0,3.5,0]'::vector::sparsevec;
 SELECT '[0,1.5,0,3.5,0]'::vector::sparsevec(5);
 SELECT '[0,1.5,0,3.5,0]'::vector::sparsevec(4);
--- a/test/sql/copy.sql
+++ b/test/sql/copy.sql
@@ -28,6 +28,21 @@ SELECT * FROM t2 ORDER BY val;
 DROP TABLE t;
 DROP TABLE t2;

+-- intvec
+
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+
+CREATE TABLE t2 (val intvec(3));
+
+\copy t TO 'results/intvec.bin' WITH (FORMAT binary)
+\copy t2 FROM 'results/intvec.bin' WITH (FORMAT binary)
+
+SELECT * FROM t2 ORDER BY val;
+
+DROP TABLE t;
+DROP TABLE t2;
+
 -- sparsevec

 CREATE TABLE t (val sparsevec(3));
--- a/test/sql/halfvec.sql
+++ b/test/sql/halfvec.sql
@@ -121,7 +121,6 @@ SELECT l2_normalize('[65504]'::halfvec);

 SELECT binary_quantize('[1,0,-1]'::halfvec);
 SELECT binary_quantize('[0,0.1,-0.2,-0.3,0.4,0.5,0.6,-0.7,0.8,-0.9,1]'::halfvec);
-SELECT binary_quantize('[1,2,3,-4,5,6,-7,8,1,-2,-3,4,5,-6,7,8,-1,2,3]'::halfvec);

 SELECT subvector('[1,2,3,4,5]'::halfvec, 1, 3);
 SELECT subvector('[1,2,3,4,5]'::halfvec, 3, 2);
--- a/test/sql/hnsw_intvec.sql
+++ b/test/sql/hnsw_intvec.sql
@@ -0,0 +1,58 @@
+SET enable_seqscan = off;
+
+-- L2
+
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_l2_ops);
+
+INSERT INTO t (val) VALUES ('[1,2,4]');
+
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <-> (SELECT NULL::intvec)) t2;
+SELECT COUNT(*) FROM t;
+
+TRUNCATE t;
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+
+DROP TABLE t;
+
+-- inner product
+
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_ip_ops);
+
+INSERT INTO t (val) VALUES ('[1,2,4]');
+
+SELECT * FROM t ORDER BY val <#> '[3,3,3]';
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <#> (SELECT NULL::intvec)) t2;
+
+DROP TABLE t;
+
+-- cosine
+
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_cosine_ops);
+
+INSERT INTO t (val) VALUES ('[1,2,4]');
+
+SELECT * FROM t ORDER BY val <=> '[3,3,3]';
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> '[0,0,0]') t2;
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <=> (SELECT NULL::intvec)) t2;
+
+DROP TABLE t;
+
+-- L1
+
+CREATE TABLE t (val intvec(3));
+INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
+CREATE INDEX ON t USING hnsw (val intvec_l1_ops);
+
+INSERT INTO t (val) VALUES ('[1,2,4]');
+
+SELECT * FROM t ORDER BY val <+> '[3,3,3]';
+SELECT COUNT(*) FROM (SELECT * FROM t ORDER BY val <+> (SELECT NULL::intvec)) t2;
+
+DROP TABLE t;
--- a/test/sql/hnsw_vector.sql
+++ b/test/sql/hnsw_vector.sql
@@ -63,17 +63,14 @@ CREATE TABLE t (val vector(3));
 INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
 CREATE INDEX ON t USING hnsw (val vector_l2_ops);

-SET hnsw.iterative_scan = strict_order;
+SET hnsw.iterative_search = strict_order;
 SET hnsw.ef_search = 1;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';

-SET hnsw.iterative_scan = relaxed_order;
+SET hnsw.iterative_search = relaxed_order;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';

-TRUNCATE t;
-SELECT * FROM t ORDER BY val <-> '[3,3,3]';
-
-RESET hnsw.iterative_scan;
+RESET hnsw.iterative_search;
 RESET hnsw.ef_search;
 DROP TABLE t;

@@ -101,17 +98,12 @@ SHOW hnsw.ef_search;
 SET hnsw.ef_search = 0;
 SET hnsw.ef_search = 1001;

-SHOW hnsw.iterative_scan;
+SHOW hnsw.iterative_search;

-SET hnsw.iterative_scan = on;
+SET hnsw.iterative_search = on;

-SHOW hnsw.max_scan_tuples;
+SHOW hnsw.max_search_tuples;

-SET hnsw.max_scan_tuples = 0;
-
-SHOW hnsw.scan_mem_multiplier;
-
-SET hnsw.scan_mem_multiplier = 0;
-SET hnsw.scan_mem_multiplier = 1001;
+SET hnsw.max_search_tuples = -2;

 DROP TABLE t;
--- a/test/sql/intvec.sql
+++ b/test/sql/intvec.sql
@@ -0,0 +1,73 @@
+SELECT '[1,2,3]'::intvec;
+SELECT '[-1,-2,-3]'::intvec;
+SELECT ' [ 1,  2 ,    3  ] '::intvec;
+SELECT '[1.23456]'::intvec;
+SELECT '[hello,1]'::intvec;
+SELECT '[127,-128]'::intvec;
+SELECT '[128,-129]'::intvec;
+SELECT '[1,2,3'::intvec;
+SELECT '[1,2,3]9'::intvec;
+SELECT '1,2,3'::intvec;
+SELECT ''::intvec;
+SELECT '['::intvec;
+SELECT '[,'::intvec;
+SELECT '[]'::intvec;
+SELECT '[1,]'::intvec;
+SELECT '[1a]'::intvec;
+SELECT '[1,,3]'::intvec;
+SELECT '[1, ,3]'::intvec;
+
+SELECT '[1,2,3]'::intvec(3);
+SELECT '[1,2,3]'::intvec(2);
+SELECT '[1,2,3]'::intvec(3, 2);
+SELECT '[1,2,3]'::intvec('a');
+SELECT '[1,2,3]'::intvec(0);
+SELECT '[1,2,3]'::intvec(16001);
+
+SELECT unnest('{"[1,2,3]", "[4,5,6]"}'::intvec[]);
+SELECT '{"[1,2,3]"}'::intvec(2)[];
+
+SELECT '[1,2,3]'::intvec < '[1,2,3]';
+SELECT '[1,2,3]'::intvec < '[1,2]';
+SELECT '[1,2,3]'::intvec <= '[1,2,3]';
+SELECT '[1,2,3]'::intvec <= '[1,2]';
+SELECT '[1,2,3]'::intvec = '[1,2,3]';
+SELECT '[1,2,3]'::intvec = '[1,2]';
+SELECT '[1,2,3]'::intvec != '[1,2,3]';
+SELECT '[1,2,3]'::intvec != '[1,2]';
+SELECT '[1,2,3]'::intvec >= '[1,2,3]';
+SELECT '[1,2,3]'::intvec >= '[1,2]';
+SELECT '[1,2,3]'::intvec > '[1,2,3]';
+SELECT '[1,2,3]'::intvec > '[1,2]';
+
+SELECT intvec_cmp('[1,2,3]', '[1,2,3]');
+SELECT intvec_cmp('[1,2,3]', '[0,0,0]');
+SELECT intvec_cmp('[0,0,0]', '[1,2,3]');
+SELECT intvec_cmp('[1,2]', '[1,2,3]');
+SELECT intvec_cmp('[1,2,3]', '[1,2]');
+SELECT intvec_cmp('[1,2]', '[2,3,4]');
+SELECT intvec_cmp('[2,3]', '[1,2,3]');
+
+SELECT vector_dims('[1,2,3]'::intvec);
+
+SELECT l2_distance('[0,0]'::intvec, '[3,4]');
+SELECT l2_distance('[0,0]'::intvec, '[0,1]');
+SELECT l2_distance('[1,2]'::intvec, '[3]');
+SELECT '[0,0]'::intvec <-> '[3,4]';
+
+SELECT inner_product('[1,2]'::intvec, '[3,4]');
+SELECT inner_product('[1,2]'::intvec, '[3]');
+SELECT inner_product('[127]'::intvec, '[127]');
+SELECT '[1,2]'::intvec <#> '[3,4]';
+
+SELECT cosine_distance('[1,2]'::intvec, '[2,4]');
+SELECT cosine_distance('[1,2]'::intvec, '[0,0]');
+SELECT cosine_distance('[1,1]'::intvec, '[1,1]');
+SELECT cosine_distance('[1,0]'::intvec, '[0,2]');
+SELECT cosine_distance('[1,1]'::intvec, '[-1,-1]');
+SELECT cosine_distance('[1,2]'::intvec, '[3]');
+SELECT '[1,2]'::intvec <=> '[2,4]';
+
+SELECT l1_distance('[0,0]'::intvec, '[3,4]');
+SELECT l1_distance('[0,0]'::intvec, '[0,1]');
+SELECT l1_distance('[1,2]'::intvec, '[3]');
--- a/test/sql/ivfflat_vector.sql
+++ b/test/sql/ivfflat_vector.sql
@@ -50,7 +50,10 @@ CREATE TABLE t (val vector(3));
 INSERT INTO t (val) VALUES ('[0,0,0]'), ('[1,2,3]'), ('[1,1,1]'), (NULL);
 CREATE INDEX ON t USING ivfflat (val vector_l2_ops) WITH (lists = 3);

-SET ivfflat.iterative_scan = relaxed_order;
+SET ivfflat.iterative_search = relaxed_order;
+SELECT * FROM t ORDER BY val <-> '[3,3,3]';
+
+SET ivfflat.max_probes = 0;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';

 SET ivfflat.max_probes = 1;
@@ -59,10 +62,7 @@ SELECT * FROM t ORDER BY val <-> '[3,3,3]';
 SET ivfflat.max_probes = 2;
 SELECT * FROM t ORDER BY val <-> '[3,3,3]';

-TRUNCATE t;
-SELECT * FROM t ORDER BY val <-> '[3,3,3]';
-
-RESET ivfflat.iterative_scan;
+RESET ivfflat.iterative_search;
 RESET ivfflat.max_probes;
 DROP TABLE t;

@@ -87,13 +87,13 @@ SHOW ivfflat.probes;
 SET ivfflat.probes = 0;
 SET ivfflat.probes = 32769;

-SHOW ivfflat.iterative_scan;
+SHOW ivfflat.iterative_search;

-SET ivfflat.iterative_scan = on;
+SET ivfflat.iterative_search = on;

 SHOW ivfflat.max_probes;

-SET ivfflat.max_probes = 0;
+SET ivfflat.max_probes = -2;
 SET ivfflat.max_probes = 32769;

 DROP TABLE t;
--- a/test/sql/vector_type.sql
+++ b/test/sql/vector_type.sql
@@ -128,7 +128,6 @@ SELECT l2_normalize('[3e38]'::vector);

 SELECT binary_quantize('[1,0,-1]'::vector);
 SELECT binary_quantize('[0,0.1,-0.2,-0.3,0.4,0.5,0.6,-0.7,0.8,-0.9,1]'::vector);
-SELECT binary_quantize('[1,2,3,-4,5,6,-7,8,1,-2,-3,4,5,-6,7,8,-1,2,3]'::vector);

 SELECT subvector('[1,2,3,4,5]'::vector, 1, 3);
 SELECT subvector('[1,2,3,4,5]'::vector, 3, 2);
--- a/test/t/005_ivfflat_query_recall.pl
+++ b/test/t/005_ivfflat_query_recall.pl
@@ -16,19 +16,29 @@ $node->safe_psql("postgres",
 	"INSERT INTO tst SELECT i, ARRAY[random(), random(), random()] FROM generate_series(1, 100000) i;"
 );

-# Add index
-$node->safe_psql("postgres", "CREATE INDEX ON tst USING ivfflat (v vector_l2_ops);");
+# Check each index type
+my @operators = ("<->", "<#>", "<=>");
+my @opclasses = ("vector_l2_ops", "vector_ip_ops", "vector_cosine_ops");

-# Test 100% recall
-for (1 .. 20)
+for my $i (0 .. $#operators)
 {
-	my $id = int(rand() * 100000);
-	my $query = $node->safe_psql("postgres", "SELECT v FROM tst WHERE i = $id;");
-	my $res = $node->safe_psql("postgres", qq(
-		SET enable_seqscan = off;
-		SELECT v FROM tst ORDER BY v <-> '$query' LIMIT 1;
-	));
-	is($res, $query);
+	my $operator = $operators[$i];
+	my $opclass = $opclasses[$i];
+
+	# Add index
+	$node->safe_psql("postgres", "CREATE INDEX ON tst USING ivfflat (v $opclass);");
+
+	# Test 100% recall
+	for (1 .. 20)
+	{
+		my $id = int(rand() * 100000);
+		my $query = $node->safe_psql("postgres", "SELECT v FROM tst WHERE i = $id;");
+		my $res = $node->safe_psql("postgres", qq(
+			SET enable_seqscan = off;
+			SELECT v FROM tst ORDER BY v <-> '$query' LIMIT 1;
+		));
+		is($res, $query);
+	}
 }

 done_testing();
--- a/test/t/033_comparison.pl
+++ b/test/t/033_comparison.pl
@@ -40,6 +40,10 @@ for (1 .. 50)
 	$actual = $node->safe_psql("postgres", "SELECT halfvec_cmp(v::halfvec, '$query'::real[]::halfvec) FROM tst");
 	is($expected, $actual);

+	# Test intvec
+	$actual = $node->safe_psql("postgres", "SELECT intvec_cmp(v::integer[]::intvec, '$query'::integer[]::intvec) FROM tst");
+	is($expected, $actual);
+
 	# Test sparsevec
 	$actual = $node->safe_psql("postgres", "SELECT sparsevec_cmp(v::vector::sparsevec, '$query'::real[]::vector::sparsevec) FROM tst");
 	is($expected, $actual);
--- a/test/t/034_distance_functions.pl
+++ b/test/t/034_distance_functions.pl
@@ -45,6 +45,10 @@ for my $function (@functions)
 		my $actual = $node->safe_psql("postgres", "SELECT $function(v::halfvec, '$query'::vector::halfvec) FROM tst");
 		is($expected, $actual, "halfvec $function");

+		# Test intvec
+		$actual = $node->safe_psql("postgres", "SELECT $function(v::real[]::integer[]::intvec, '$query'::vector::real[]::integer[]::intvec) FROM tst");
+		is($expected, $actual, "intvec $function");
+
 		# Test sparsevec
 		$actual = $node->safe_psql("postgres", "SELECT $function(v::sparsevec, '$query'::vector::sparsevec) FROM tst");
 		is($expected, $actual, "sparsevec $function");
--- a/test/t/037_inputs.pl
+++ b/test/t/037_inputs.pl
@@ -12,8 +12,8 @@ $node->start;
 # Create extension
 $node->safe_psql("postgres", "CREATE EXTENSION vector;");

-my @types = ("vector", "halfvec", "sparsevec");
-my @inputs = ("[1.23,4.56,7.89]", "[1.23,4.56,7.89]", "{1:1.23,2:4.56,3:7.89}/3");
+my @types = ("vector", "halfvec", "intvec", "sparsevec");
+my @inputs = ("[1.23,4.56,7.89]", "[1.23,4.56,7.89]", "[1,2,3]", "{1:1.23,2:4.56,3:7.89}/3");
 my @subs = (" ", " ", ",", ":", "-", "1", "9", "\0", "2147483648", "-2147483649");

 for my $i (0 .. $#types)
--- a/test/t/041_ivfflat_iterative_search.pl
+++ b/test/t/041_ivfflat_iterative_search.pl
@@ -23,7 +23,7 @@ $node->safe_psql("postgres", "CREATE INDEX ON tst USING ivfflat (v vector_l2_ops
 my $count = $node->safe_psql("postgres", qq(
 	SET enable_seqscan = off;
 	SET ivfflat.probes = 10;
-	SET ivfflat.iterative_scan = relaxed_order;
+	SET ivfflat.iterative_search = relaxed_order;
 	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
 ));
 is($count, 10);
@@ -39,7 +39,7 @@ foreach ((30, 50, 70))
 		$count = $node->safe_psql("postgres", qq(
 			SET enable_seqscan = off;
 			SET ivfflat.probes = 10;
-			SET ivfflat.iterative_scan = relaxed_order;
+			SET ivfflat.iterative_search = relaxed_order;
 			SET ivfflat.max_probes = $max_probes;
 			SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst WHERE i = $i) LIMIT 11) t;
 		));
--- a/test/t/042_ivfflat_iterative_search_recall.pl
+++ b/test/t/042_ivfflat_iterative_search_recall.pl
@@ -19,7 +19,7 @@ sub test_recall
 	my $explain = $node->safe_psql("postgres", qq(
 		SET enable_seqscan = off;
 		SET ivfflat.probes = $probes;
-		SET ivfflat.iterative_scan = relaxed_order;
+		SET ivfflat.iterative_search = relaxed_order;
 		EXPLAIN ANALYZE SELECT i FROM tst WHERE i % $c = 0 ORDER BY v $operator '$queries[0]' LIMIT $limit;
 	));
 	like($explain, qr/Index Scan using idx on tst/);
@@ -29,7 +29,7 @@ sub test_recall
 		my $actual = $node->safe_psql("postgres", qq(
 			SET enable_seqscan = off;
 			SET ivfflat.probes = $probes;
-			SET ivfflat.iterative_scan = relaxed_order;
+			SET ivfflat.iterative_search = relaxed_order;
 			SELECT i FROM tst WHERE i % $c = 0 ORDER BY v $operator '$queries[$i]' LIMIT $limit;
 		));
 		my @actual_ids = split("\n", $actual);
--- a/test/t/043_hnsw_iterative_search.pl
+++ b/test/t/043_hnsw_iterative_search.pl
@@ -26,9 +26,8 @@ $node->safe_psql("postgres", qq(

 my $count = $node->safe_psql("postgres", qq(
 	SET enable_seqscan = off;
-	SET hnsw.iterative_scan = relaxed_order;
-	SET hnsw.max_scan_tuples = 100000;
-	SET hnsw.scan_mem_multiplier = 2;
+	SET hnsw.iterative_search = relaxed_order;
+	SET work_mem = '8MB';
 	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
 ));
 is($count, 10);
@@ -43,9 +42,9 @@ foreach ((30000, 50000, 70000))
 	{
 		$count = $node->safe_psql("postgres", qq(
 			SET enable_seqscan = off;
-			SET hnsw.iterative_scan = relaxed_order;
-			SET hnsw.max_scan_tuples = $max_tuples;
-			SET hnsw.scan_mem_multiplier = 2;
+			SET hnsw.iterative_search = relaxed_order;
+			SET hnsw.max_search_tuples = $max_tuples;
+			SET work_mem = '8MB';
 			SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst WHERE i = $i) LIMIT 11) t;
 		));
 		$sum += $count;
@@ -56,4 +55,13 @@ foreach ((30000, 50000, 70000))
 	cmp_ok($avg, '<', $expected + 2);
 }

+my ($ret, $stdout, $stderr) = $node->psql("postgres", qq(
+	SET enable_seqscan = off;
+	SET hnsw.iterative_search = relaxed_order;
+	SET client_min_messages = debug1;
+	SET work_mem = '2MB';
+	SELECT COUNT(*) FROM (SELECT v FROM tst WHERE i % 10000 = 0 ORDER BY v <-> (SELECT v FROM tst LIMIT 1) LIMIT 11) t;
+));
+like($stderr, qr/hnsw index scan exceeded work_mem after \d+ tuples/);
+
 done_testing();
--- a/test/t/044_hnsw_iterative_search_recall.pl
+++ b/test/t/044_hnsw_iterative_search_recall.pl
@@ -21,7 +21,7 @@ sub test_recall
 	my $explain = $node->safe_psql("postgres", qq(
 		SET enable_seqscan = off;
 		SET hnsw.ef_search = $ef_search;
-		SET hnsw.iterative_scan = $mode;
+		SET hnsw.iterative_search = $mode;
 		EXPLAIN ANALYZE SELECT i FROM tst WHERE i % $c = 0 ORDER BY v $operator '$queries[0]' LIMIT $limit;
 	));
 	like($explain, qr/Index Scan using idx on tst/);
@@ -31,7 +31,7 @@ sub test_recall
 		my $actual = $node->safe_psql("postgres", qq(
 			SET enable_seqscan = off;
 			SET hnsw.ef_search = $ef_search;
-			SET hnsw.iterative_scan = $mode;
+			SET hnsw.iterative_search = $mode;
 			SELECT i FROM tst WHERE i % $c = 0 ORDER BY v $operator '$queries[$i]' LIMIT $limit;
 		));
 		my @actual_ids = split("\n", $actual);
--- a/test/t/045_hnsw_intvec_build_recall.pl
+++ b/test/t/045_hnsw_intvec_build_recall.pl
@@ -0,0 +1,132 @@
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+my $node;
+my @queries = ();
+my @expected;
+my $limit = 20;
+my $dim = 10;
+my $array_sql = join(",", ('(random() * 255)::int - 128') x $dim);
+
+sub test_recall
+{
+	my ($min, $operator) = @_;
+	my $correct = 0;
+	my $total = 0;
+
+	my $explain = $node->safe_psql("postgres", qq(
+		SET enable_seqscan = off;
+		EXPLAIN ANALYZE SELECT i FROM tst ORDER BY v $operator '$queries[0]' LIMIT $limit;
+	));
+	like($explain, qr/Index Scan/);
+
+	for my $i (0 .. $#queries)
+	{
+		my $actual = $node->safe_psql("postgres", qq(
+			SET enable_seqscan = off;
+			SELECT i FROM tst ORDER BY v $operator '$queries[$i]' LIMIT $limit;
+		));
+		my @actual_ids = split("\n", $actual);
+		my %actual_set = map { $_ => 1 } @actual_ids;
+
+		my @expected_ids = split("\n", $expected[$i]);
+
+		foreach (@expected_ids)
+		{
+			if (exists($actual_set{$_}))
+			{
+				$correct++;
+			}
+			$total++;
+		}
+	}
+
+	cmp_ok($correct / $total, ">=", $min, $operator);
+}
+
+# Initialize node
+$node = PostgreSQL::Test::Cluster->new('node');
+$node->init;
+$node->start;
+
+# Create table
+$node->safe_psql("postgres", "CREATE EXTENSION vector;");
+$node->safe_psql("postgres", "CREATE TABLE tst (i int4, v intvec($dim));");
+$node->safe_psql("postgres",
+	"INSERT INTO tst SELECT i, ARRAY[$array_sql] FROM generate_series(1, 10000) i;"
+);
+
+# Generate queries
+for (1 .. 20)
+{
+	my @r = ();
+	for (1 .. $dim)
+	{
+		push(@r, int(rand(256)) - 128);
+	}
+	push(@queries, "[" . join(",", @r) . "]");
+}
+
+# Check each index type
+my @operators = ("<->", "<#>", "<=>", "<+>");
+my @opclasses = ("intvec_l2_ops", "intvec_ip_ops", "intvec_cosine_ops", "intvec_l1_ops");
+
+for my $i (0 .. $#operators)
+{
+	my $operator = $operators[$i];
+	my $opclass = $opclasses[$i];
+
+	# Get exact results
+	@expected = ();
+	foreach (@queries)
+	{
+		my $res = $node->safe_psql("postgres", "SELECT i FROM tst ORDER BY v $operator '$_' LIMIT $limit;");
+		push(@expected, $res);
+	}
+
+	# Build index serially
+	$node->safe_psql("postgres", qq(
+		SET max_parallel_maintenance_workers = 0;
+		CREATE INDEX idx ON tst USING hnsw (v $opclass);
+	));
+
+	# Test approximate results
+	my $min = 0.98;
+	test_recall($min, $operator);
+
+	$node->safe_psql("postgres", "DROP INDEX idx;");
+
+	# Build index in parallel in memory
+	my ($ret, $stdout, $stderr) = $node->psql("postgres", qq(
+		SET client_min_messages = DEBUG;
+		SET min_parallel_table_scan_size = 1;
+		CREATE INDEX idx ON tst USING hnsw (v $opclass);
+	));
+	is($ret, 0, $stderr);
+	like($stderr, qr/using \d+ parallel workers/);
+
+	# Test approximate results
+	test_recall($min, $operator);
+
+	$node->safe_psql("postgres", "DROP INDEX idx;");
+
+	# Build index in parallel on disk
+	# Set parallel_workers on table to use workers with low maintenance_work_mem
+	($ret, $stdout, $stderr) = $node->psql("postgres", qq(
+		ALTER TABLE tst SET (parallel_workers = 2);
+		SET client_min_messages = DEBUG;
+		SET maintenance_work_mem = '4MB';
+		CREATE INDEX idx ON tst USING hnsw (v $opclass);
+		ALTER TABLE tst RESET (parallel_workers);
+	));
+	is($ret, 0, $stderr);
+	like($stderr, qr/using \d+ parallel workers/);
+	like($stderr, qr/hnsw graph no longer fits into maintenance_work_mem/);
+
+	$node->safe_psql("postgres", "DROP INDEX idx;");
+}
+
+done_testing();
--- a/test/t/045_hnsw_low_memory_build.pl
+++ b/test/t/045_hnsw_low_memory_build.pl
@@ -1,29 +0,0 @@
-use strict;
-use warnings FATAL => 'all';
-use PostgreSQL::Test::Cluster;
-use PostgreSQL::Test::Utils;
-use Test::More;
-
-# Initialize node
-my $node = PostgreSQL::Test::Cluster->new('node');
-$node->init;
-$node->start;
-
-# Create table
-$node->safe_psql("postgres", "CREATE EXTENSION vector;");
-$node->safe_psql("postgres", "CREATE TABLE tst (v vector(3));");
-$node->safe_psql("postgres",
-	"INSERT INTO tst SELECT ARRAY[random(), random(), random()] FROM generate_series(1, 1000) i;"
-);
-
-my ($ret, $stdout, $stderr) = $node->psql("postgres", qq(
-	SET client_min_messages = DEBUG;
-	SET maintenance_work_mem = '3073kB';
-	ALTER TABLE tst SET (parallel_workers = 1);
-	CREATE INDEX ON tst USING hnsw (v vector_l2_ops);
-));
-is($ret, 0, $stderr);
-like($stderr, qr/using \d+ parallel workers/);
-like($stderr, qr/hnsw graph no longer fits into maintenance_work_mem after 0 tuples/);
-
-done_testing();
--- a/test/t/046_hnsw_intvec_insert_recall.pl
+++ b/test/t/046_hnsw_intvec_insert_recall.pl
@@ -0,0 +1,113 @@
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+my $node;
+my @queries = ();
+my @expected;
+my $limit = 20;
+my $dim = 10;
+my $array_sql = join(",", ('(random() * 255)::int - 128') x $dim);
+
+sub test_recall
+{
+	my ($min, $operator) = @_;
+	my $correct = 0;
+	my $total = 0;
+
+	my $explain = $node->safe_psql("postgres", qq(
+		SET enable_seqscan = off;
+		EXPLAIN ANALYZE SELECT i FROM tst ORDER BY v $operator '$queries[0]' LIMIT $limit;
+	));
+	like($explain, qr/Index Scan/);
+
+	for my $i (0 .. $#queries)
+	{
+		my $actual = $node->safe_psql("postgres", qq(
+			SET enable_seqscan = off;
+			SELECT i FROM tst ORDER BY v $operator '$queries[$i]' LIMIT $limit;
+		));
+		my @actual_ids = split("\n", $actual);
+		my %actual_set = map { $_ => 1 } @actual_ids;
+
+		my @expected_ids = split("\n", $expected[$i]);
+
+		foreach (@expected_ids)
+		{
+			if (exists($actual_set{$_}))
+			{
+				$correct++;
+			}
+			$total++;
+		}
+	}
+
+	cmp_ok($correct / $total, ">=", $min, $operator);
+}
+
+# Initialize node
+$node = PostgreSQL::Test::Cluster->new('node');
+$node->init;
+$node->start;
+
+# Create table
+$node->safe_psql("postgres", "CREATE EXTENSION vector;");
+$node->safe_psql("postgres", "CREATE TABLE tst (i serial, v intvec($dim));");
+
+# Generate queries
+for (1 .. 20)
+{
+	my @r = ();
+	for (1 .. $dim)
+	{
+		push(@r, int(rand(256)) - 128);
+	}
+	push(@queries, "[" . join(",", @r) . "]");
+}
+
+# Check each index type
+my @operators = ("<->", "<#>", "<=>", "<+>");
+my @opclasses = ("intvec_l2_ops", "intvec_ip_ops", "intvec_cosine_ops", "intvec_l1_ops");
+
+for my $i (0 .. $#operators)
+{
+	my $operator = $operators[$i];
+	my $opclass = $opclasses[$i];
+
+	# Add index
+	$node->safe_psql("postgres", "CREATE INDEX idx ON tst USING hnsw (v $opclass);");
+
+	# Use concurrent inserts
+	$node->pgbench(
+		"--no-vacuum --client=10 --transactions=1000",
+		0,
+		[qr{actually processed}],
+		[qr{^$}],
+		"concurrent INSERTs",
+		{
+			"040_hnsw_intvec_insert_recall_$opclass" => "INSERT INTO tst (v) VALUES (ARRAY[$array_sql]);"
+		}
+	);
+
+	# Get exact results
+	@expected = ();
+	foreach (@queries)
+	{
+		my $res = $node->safe_psql("postgres", qq(
+			SET enable_indexscan = off;
+			SELECT i FROM tst ORDER BY v $operator '$_' LIMIT $limit;
+		));
+		push(@expected, $res);
+	}
+
+	# Test approximate results
+	my $min = 0.98;
+	test_recall($min, $operator);
+
+	$node->safe_psql("postgres", "DROP INDEX idx;");
+	$node->safe_psql("postgres", "TRUNCATE tst;");
+}
+
+done_testing();
--- a/test/t/046_hnsw_vacuum_scan.pl
+++ b/test/t/046_hnsw_vacuum_scan.pl
@@ -1,38 +0,0 @@
-use strict;
-use warnings FATAL => 'all';
-use PostgreSQL::Test::Cluster;
-use PostgreSQL::Test::Utils;
-use Test::More;
-
-my $dim = 3;
-my $array_sql = join(",", ('random()') x $dim);
-
-# Initialize node
-my $node = PostgreSQL::Test::Cluster->new('node');
-$node->init;
-$node->start;
-
-# Create table and index
-$node->safe_psql("postgres", "CREATE EXTENSION vector;");
-$node->safe_psql("postgres", "CREATE TABLE tst (i serial, v vector($dim));");
-$node->safe_psql("postgres", "ALTER TABLE tst SET (autovacuum_enabled = false);");
-$node->safe_psql("postgres",
-    "INSERT INTO tst (v) SELECT ARRAY[$array_sql] FROM generate_series(1, 1000) i;"
-);
-$node->safe_psql("postgres", "CREATE INDEX ON tst USING hnsw (v vector_l2_ops);");
-$node->safe_psql("postgres", "DELETE FROM tst");
-
-# Test HNSW_SCAN_LOCK at the beginning of MarkDeleted is effective
-$node->pgbench(
-    "--no-vacuum --client=5 --transactions=1000",
-    0,
-    [qr{actually processed}],
-    [qr{^$}],
-    "concurrent SELECTs and VACUUM",
-    {
-        "046_hnsw_vacuum_scan_select\@1000" => "SELECT i FROM tst ORDER BY v <-> '[0,0,0]' LIMIT 10;",
-        "046_hnsw_vacuum_scan_vacuum\@1" => "VACUUM tst;"
-    }
-);
-
-done_testing();
--- a/test/t/047_hnsw_intvec_vacuum_recall.pl
+++ b/test/t/047_hnsw_intvec_vacuum_recall.pl
@@ -0,0 +1,101 @@
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+my $node;
+my @queries = ();
+my @expected;
+my $limit = 20;
+my $dim = 10;
+my $array_sql = join(",", ('(random() * 255)::int - 128') x $dim);
+
+sub test_recall
+{
+	my ($min, $ef_search, $test_name) = @_;
+	my $correct = 0;
+	my $total = 0;
+
+	my $explain = $node->safe_psql("postgres", qq(
+		SET enable_seqscan = off;
+		SET hnsw.ef_search = $ef_search;
+		EXPLAIN ANALYZE SELECT i FROM tst ORDER BY v <-> '$queries[0]' LIMIT $limit;
+	));
+	like($explain, qr/Index Scan/);
+
+	for my $i (0 .. $#queries)
+	{
+		my $actual = $node->safe_psql("postgres", qq(
+			SET enable_seqscan = off;
+			SET hnsw.ef_search = $ef_search;
+			SELECT i FROM tst ORDER BY v <-> '$queries[$i]' LIMIT $limit;
+		));
+		my @actual_ids = split("\n", $actual);
+		my %actual_set = map { $_ => 1 } @actual_ids;
+
+		my @expected_ids = split("\n", $expected[$i]);
+
+		foreach (@expected_ids)
+		{
+			if (exists($actual_set{$_}))
+			{
+				$correct++;
+			}
+			$total++;
+		}
+	}
+
+	cmp_ok($correct / $total, ">=", $min, $test_name);
+}
+
+# Initialize node
+$node = PostgreSQL::Test::Cluster->new('node');
+$node->init;
+$node->start;
+
+# Create table
+$node->safe_psql("postgres", "CREATE EXTENSION vector;");
+$node->safe_psql("postgres", "CREATE TABLE tst (i int4, v intvec($dim));");
+$node->safe_psql("postgres", "ALTER TABLE tst SET (autovacuum_enabled = false);");
+$node->safe_psql("postgres",
+	"INSERT INTO tst SELECT i, ARRAY[$array_sql] FROM generate_series(1, 10000) i;"
+);
+
+# Add index
+$node->safe_psql("postgres", "CREATE INDEX ON tst USING hnsw (v intvec_l2_ops) WITH (m = 4, ef_construction = 8);");
+
+# Delete data
+$node->safe_psql("postgres", "DELETE FROM tst WHERE i > 2500;");
+
+# Generate queries
+for (1 .. 20)
+{
+	my @r = ();
+	for (1 .. $dim)
+	{
+		push(@r, int(rand(256)) - 128);
+	}
+	push(@queries, "[" . join(",", @r) . "]");
+}
+
+# Get exact results
+@expected = ();
+foreach (@queries)
+{
+	my $res = $node->safe_psql("postgres", qq(
+		SET enable_indexscan = off;
+		SELECT i FROM tst ORDER BY v <-> '$_' LIMIT $limit;
+	));
+	push(@expected, $res);
+}
+
+test_recall(0.18, $limit, "before vacuum");
+test_recall(0.84, 100, "before vacuum");
+
+# TODO Test concurrent inserts with vacuum
+$node->safe_psql("postgres", "VACUUM tst;");
+
+test_recall(0.84, $limit, "after vacuum");
+
+done_testing();
--- a/test/t/047_hnsw_vacuum_insert.pl
+++ b/test/t/047_hnsw_vacuum_insert.pl
@@ -1,39 +0,0 @@
-use strict;
-use warnings FATAL => 'all';
-use PostgreSQL::Test::Cluster;
-use PostgreSQL::Test::Utils;
-use Test::More;
-
-my $dim = 3;
-my $array_sql = join(",", ('random()') x $dim);
-
-# Initialize node
-my $node = PostgreSQL::Test::Cluster->new('node');
-$node->init;
-$node->start;
-
-# Create table and index
-$node->safe_psql("postgres", "CREATE EXTENSION vector;");
-$node->safe_psql("postgres", "CREATE TABLE tst (i serial, v vector($dim));");
-$node->safe_psql("postgres", "ALTER TABLE tst SET (autovacuum_enabled = false);");
-$node->safe_psql("postgres",
-    "INSERT INTO tst (v) SELECT ARRAY[$array_sql] FROM generate_series(1, 1000) i;"
-);
-$node->safe_psql("postgres", "CREATE INDEX ON tst USING hnsw (v vector_l2_ops);");
-
-# Test no "hnsw graph not repaired" errors
-$node->pgbench(
-    "--no-vacuum --client=5 --transactions=1000",
-    0,
-    [qr{actually processed}],
-    [qr{^$}],
-    "concurrent INSERTs, DELETEs, SELECTs, and VACUUM",
-    {
-        "047_hnsw_vacuum_insert_insert\@500" => "INSERT INTO tst (v) VALUES (ARRAY[$array_sql]);",
-        "047_hnsw_vacuum_insert_delete\@500" => "DELETE FROM tst WHERE i = (SELECT i FROM tst LIMIT 1);",
-        "047_hnsw_vacuum_insert_select\@20" => "SELECT i FROM tst ORDER BY v <-> '[0,0,0]' LIMIT 10;",
-        "047_hnsw_vacuum_insert_vacuum\@1" => "VACUUM tst;"
-    }
-);
-
-done_testing();
--- a/test/t/048_hnsw_intvec_duplicates.pl
+++ b/test/t/048_hnsw_intvec_duplicates.pl
@@ -0,0 +1,58 @@
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+# Initialize node
+my $node = PostgreSQL::Test::Cluster->new('node');
+$node->init;
+$node->start;
+
+# Create table
+$node->safe_psql("postgres", "CREATE EXTENSION vector;");
+$node->safe_psql("postgres", "CREATE TABLE tst (v intvec(3));");
+
+sub insert_vectors
+{
+	for my $i (1 .. 20)
+	{
+		$node->safe_psql("postgres", "INSERT INTO tst VALUES ('[1,1,1]');");
+	}
+}
+
+sub test_duplicates
+{
+	my $res = $node->safe_psql("postgres", qq(
+		SET enable_seqscan = off;
+		SET hnsw.ef_search = 1;
+		SELECT COUNT(*) FROM (SELECT * FROM tst ORDER BY v <-> '[1,1,1]') t;
+	));
+	is($res, 10);
+}
+
+# Test duplicates with build
+insert_vectors();
+$node->safe_psql("postgres", "CREATE INDEX idx ON tst USING hnsw (v intvec_l2_ops);");
+test_duplicates();
+
+# Reset
+$node->safe_psql("postgres", "TRUNCATE tst;");
+
+# Test duplicates with inserts
+insert_vectors();
+test_duplicates();
+
+# Test fallback path for inserts
+$node->pgbench(
+	"--no-vacuum --client=5 --transactions=100",
+	0,
+	[qr{actually processed}],
+	[qr{^$}],
+	"concurrent INSERTs",
+	{
+		"042_hnsw_intvec_duplicates" => "INSERT INTO tst VALUES ('[1,1,1]');"
+	}
+);
+
+done_testing();
--- a/vector.control
+++ b/vector.control
@@ -1,4 +1,4 @@
 comment = 'vector data type and ivfflat and hnsw access methods'
-default_version = '0.8.4'
+default_version = '0.7.4'
 module_pathname = '$libdir/vector'
 relocatable = true
Author	SHA1	Message	Date
Andrew Kane	8d5631da72	Use integer[] for consistency [skip ci]	2024-10-13 21:15:46 -07:00
Andrew Kane	54d91e1116	Fixed CI	2024-10-13 19:52:17 -07:00
Andrew Kane	f298a72ada	Added casting [skip ci]	2024-10-13 19:46:16 -07:00
Andrew Kane	f5b225530f	Removed unneeded cast [skip ci]	2024-10-13 19:45:04 -07:00
Andrew Kane	05944f5a6f	Improved distance functions [skip ci]	2024-10-13 19:33:43 -07:00
Andrew Kane	a344ecb60d	Merge branch 'master' into intvec	2024-10-13 19:21:59 -07:00
Andrew Kane	67de46487e	Fixed flaky test [skip ci]	2024-10-13 19:20:02 -07:00
Andrew Kane	f52abfc26c	Added more TAP tests [skip ci]	2024-10-13 19:14:09 -07:00
Andrew Kane	1066b4be60	Added intvec to distance functions test [skip ci]	2024-10-13 19:01:04 -07:00
Andrew Kane	6221779f74	Added casting to int[] [skip ci]	2024-10-13 18:55:12 -07:00
Andrew Kane	4765df1c50	Updated upgrade script [skip ci]	2024-10-13 18:46:45 -07:00
Andrew Kane	9514a7ffcd	Added vector_dims [skip ci]	2024-10-13 18:46:09 -07:00
Andrew Kane	98deaa7407	Added intvec to inputs test [skip ci]	2024-10-13 18:41:57 -07:00
Andrew Kane	faa25d31f7	Added cast tests [skip ci]	2024-10-13 18:39:46 -07:00
Andrew Kane	39af767617	Fixed casting [skip ci]	2024-10-13 18:36:25 -07:00
Andrew Kane	3424f46298	Updated upgrade script [skip ci]	2024-10-13 18:27:27 -07:00
Andrew Kane	ab12f1622d	Added more intvec functions [skip ci]	2024-10-13 18:14:31 -07:00
Andrew Kane	2fb71a6183	Updated readme [skip ci]	2024-10-13 18:02:43 -07:00
Andrew Kane	67b4ba5a14	Updated readme [skip ci]	2024-09-27 21:30:53 -07:00
Andrew Kane	8597eb79aa	Restored isnan check [skip ci]	2024-09-23 13:44:29 -07:00
Andrew Kane	ffca8e720c	Exclude zero vectors for cosine distance to be consistent with other types [skip ci]	2024-09-23 13:35:36 -07:00
Andrew Kane	0296a08ccf	Added L1 distance to test [skip ci]	2024-09-23 13:25:22 -07:00
Andrew Kane	b067b5f073	Added intvec type	2024-09-23 13:20:49 -07:00