From bf28ed8176cd19edbe30f7ccbc25fa299a8b0298 Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Wed, 18 Jun 2025 10:57:18 -0700
Subject: [PATCH] Set random seed for IVFFLAT_BENCH [skip ci]

---
 src/ivfbuild.c | 4 ++++
 src/ivfflat.h  | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/src/ivfbuild.c b/src/ivfbuild.c
index 944f07b..c51f408 100644
--- a/src/ivfbuild.c
+++ b/src/ivfbuild.c
@@ -1023,6 +1023,10 @@ 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));
diff --git a/src/ivfflat.h b/src/ivfflat.h
index c296b66..76608f3 100644
--- a/src/ivfflat.h
+++ b/src/ivfflat.h
@@ -73,9 +73,11 @@
 #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 */