From 7f1711f29dd6e44753d5845f707bda5fac6166a0 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 21 Nov 2004 22:48:01 +0000 Subject: [PATCH] Reduce the default size of the PortalHashTable in order to save a few cycles during transaction exit. A typical session probably wouldn't have as many as half a dozen portals open at once, so the original value of 64 seems far larger than needed. --- src/backend/utils/mmgr/portalmem.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c index 23afef4f41..e7fa2cdd18 100644 --- a/src/backend/utils/mmgr/portalmem.c +++ b/src/backend/utils/mmgr/portalmem.c @@ -12,7 +12,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/mmgr/portalmem.c,v 1.74 2004/10/12 01:50:04 neilc Exp $ + * $PostgreSQL: pgsql/src/backend/utils/mmgr/portalmem.c,v 1.75 2004/11/21 22:48:01 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -26,10 +26,13 @@ #include "utils/portal.h" /* - * estimate of the maximum number of open portals a user would have, - * used in initially sizing the PortalHashTable in EnablePortalManager() + * Estimate of the maximum number of open portals a user would have, + * used in initially sizing the PortalHashTable in EnablePortalManager(). + * Since the hash table can expand, there's no need to make this overly + * generous, and keeping it small avoids unnecessary overhead in the + * hash_seq_search() calls executed during transaction end. */ -#define PORTALS_PER_USER 64 +#define PORTALS_PER_USER 16 /* ----------------