Added benchmarking for HNSW vacuuming [skip ci]

.github/workflows/build.yml

@@ -97,7 +97,7 @@ jobs:
         with:
           postgres-version: ${{ matrix.postgres }}
       - run: |
-          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
+          call "C:\Program Files\Microsoft Visual Studio\${{ matrix.os == 'windows-2025' && 18 || 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' || '' }} && ^

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.8.3 (unreleased)
+
+- 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)

README.md

@@ -1329,7 +1329,7 @@ make clean && PG_CFLAGS="-DUSE_ASSERT_CHECKING" make && make install
 To enable benchmarking:
 
 ```sh
-make clean && PG_CFLAGS="-DIVFFLAT_BENCH" make && make install
+make clean && PG_CFLAGS="-DHNSW_BENCH -DIVFFLAT_BENCH" make && make install
 ```
 
 To show memory usage:

src/bitutils.c

@@ -31,10 +31,12 @@
 #define BIT_TARGET_CLONES
 #endif
 
-/* Use built-ins when possible for inlining */
-#if defined(HAVE__BUILTIN_POPCOUNT) && defined(HAVE_LONG_INT_64)
+/* 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)
 #define popcount64(x) __builtin_popcountl(x)
-#elif defined(HAVE__BUILTIN_POPCOUNT) && defined(HAVE_LONG_LONG_INT_64)
+#elif defined(HAVE__BUILTIN_POPCOUNT) && (defined(HAVE_LONG_LONG_INT_64) || SIZEOF_LONG_LONG == 8)
 #define popcount64(x) __builtin_popcountll(x)
 #elif !defined(_MSC_VER)
 /* Fails to resolve with MSVC */

src/hnsw.c

@@ -279,7 +279,6 @@ hnswhandler(PG_FUNCTION_ARGS)
 		.amconsistentequality = false,
 		.amconsistentordering = false,
 		.amcanbackward = false,
-		.amcanmarkpos = false,
 		.amcanunique = false,
 		.amcanmulticol = false,
 		.amoptionalkey = true,
@@ -313,13 +312,10 @@ hnswhandler(PG_FUNCTION_ARGS)
 		.ambeginscan = hnswbeginscan,
 		.amrescan = hnswrescan,
 		.amgettuple = hnswgettuple,
-		.amgetbatch = NULL,
-		.amunguardbatch = NULL,
-		.amkillitemsbatch = NULL,
-		.amgettransform = NULL,
 		.amgetbitmap = NULL,
 		.amendscan = hnswendscan,
-		.amposreset = NULL,
+		.ammarkpos = NULL,
+		.amrestrpos = NULL,
 		.amestimateparallelscan = NULL,
 		.aminitparallelscan = NULL,
 		.amparallelrescan = NULL,

src/hnsw.h

@@ -18,6 +18,10 @@
 #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
@@ -78,6 +82,21 @@ 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)

src/hnswvacuum.c

@@ -634,13 +634,13 @@ hnswbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
 	InitVacuumState(&vacuumstate, info, stats, callback, callback_state);
 
 	/* Pass 1: Remove heap TIDs */
-	RemoveHeapTids(&vacuumstate);
+	HnswBench("RemoveHeapTids", RemoveHeapTids(&vacuumstate));
 
 	/* Pass 2: Repair graph */
-	RepairGraph(&vacuumstate);
+	HnswBench("RepairGraph", RepairGraph(&vacuumstate));
 
 	/* Pass 3: Mark as deleted */
-	MarkDeleted(&vacuumstate);
+	HnswBench("MarkDeleted", MarkDeleted(&vacuumstate));
 
 	FreeVacuumState(&vacuumstate);
 

src/ivfflat.c

@@ -196,7 +196,6 @@ ivfflathandler(PG_FUNCTION_ARGS)
 		.amconsistentequality = false,
 		.amconsistentordering = false,
 		.amcanbackward = false,
-		.amcanmarkpos = false,
 		.amcanunique = false,
 		.amcanmulticol = false,
 		.amoptionalkey = true,
@@ -230,13 +229,10 @@ ivfflathandler(PG_FUNCTION_ARGS)
 		.ambeginscan = ivfflatbeginscan,
 		.amrescan = ivfflatrescan,
 		.amgettuple = ivfflatgettuple,
-		.amgetbatch = NULL,
-		.amunguardbatch = NULL,
-		.amkillitemsbatch = NULL,
-		.amgettransform = NULL,
 		.amgetbitmap = NULL,
 		.amendscan = ivfflatendscan,
-		.amposreset = NULL,
+		.ammarkpos = NULL,
+		.amrestrpos = NULL,
 		.amestimateparallelscan = NULL,
 		.aminitparallelscan = NULL,
 		.amparallelrescan = NULL,