v11-0002-Use-fasthash-for-pgstat_hash_hash_key.patch
application/x-patch
Filename: v11-0002-Use-fasthash-for-pgstat_hash_hash_key.patch
Type: application/x-patch
Part: 7
Patch
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API reference →
Format: format-patch
Series: patch v11-0002
Subject: Use fasthash for pgstat_hash_hash_key
| File | + | − |
|---|---|---|
| src/include/utils/pgstat_internal.h | 2 | 7 |
From 04afcddc051abc2727cd413e9000ecaba4b38037 Mon Sep 17 00:00:00 2001
From: John Naylor <john.naylor@postgresql.org>
Date: Sat, 9 Dec 2023 16:24:56 +0700
Subject: [PATCH v11 2/8] Use fasthash for pgstat_hash_hash_key
Previously this called the 32-bit Murmur finalizer on the three elements,
then joined with hash_combine(). Fasthash is simpler, executes faster
and takes up less binary space. While the collision and bias behavior
were almost certainly fine with the previous coding, now we have
measurements to prove it.
Discussion:
---
src/include/utils/pgstat_internal.h | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 60fbf9394b..ecc46bef04 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -14,7 +14,7 @@
#define PGSTAT_INTERNAL_H
-#include "common/hashfn.h"
+#include "common/hashfn_unstable.h"
#include "lib/dshash.h"
#include "lib/ilist.h"
#include "pgstat.h"
@@ -777,15 +777,10 @@ static inline uint32
pgstat_hash_hash_key(const void *d, size_t size, void *arg)
{
const PgStat_HashKey *key = (PgStat_HashKey *) d;
- uint32 hash;
Assert(size == sizeof(PgStat_HashKey) && arg == NULL);
- hash = murmurhash32(key->kind);
- hash = hash_combine(hash, murmurhash32(key->dboid));
- hash = hash_combine(hash, murmurhash32(key->objoid));
-
- return hash;
+ return fasthash32((const char *) key, size, 0);
}
/*
--
2.43.0