From 91fe2e62e7fc2095e8fde66197f0e03cd7ca214a Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Tue, 16 Jun 2026 09:53:47 -0700
Subject: [PATCH] Added benchmarking for HNSW vacuuming [skip ci]

---
 README.md        |  2 +-
 src/hnsw.h       | 19 +++++++++++++++++++
 src/hnswvacuum.c |  6 +++---
 3 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 30a4afb..b0cad60 100644
--- a/README.md
+++ b/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:
diff --git a/src/hnsw.h b/src/hnsw.h
index f4492b5..08293be 100644
--- a/src/hnsw.h
+++ b/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)
diff --git a/src/hnswvacuum.c b/src/hnswvacuum.c
index fe0e980..7ccd313 100644
--- a/src/hnswvacuum.c
+++ b/src/hnswvacuum.c
@@ -669,13 +669,13 @@ 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);