From 0164a0f9ee12e0eff9e4c661358a272ecd65c2d4 Mon Sep 17 00:00:00 2001 From: Nathan Bossart Date: Thu, 20 Mar 2025 10:16:50 -0500 Subject: Add vacuum_truncate configuration parameter. This new parameter works just like the storage parameter of the same name: if set to true (which is the default), autovacuum and VACUUM attempt to truncate any empty pages at the end of the table. It is primarily intended to help users avoid locking issues on hot standbys. The setting can be overridden with the storage parameter or VACUUM's TRUNCATE option. Since there's presently no way to determine whether a Boolean storage parameter is explicitly set or has just picked up the default value, this commit also introduces an isset_offset member to relopt_parse_elt. Suggested-by: Will Storey Author: Nathan Bossart Co-authored-by: Gurjeet Singh Reviewed-by: Laurenz Albe Reviewed-by: Fujii Masao Reviewed-by: Robert Treat Discussion: https://postgr.es/m/Z2DE4lDX4tHqNGZt%40dev.null --- src/backend/commands/vacuum.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'src/backend/commands') diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c index e81c9a8aba3..f0a7b87808d 100644 --- a/src/backend/commands/vacuum.c +++ b/src/backend/commands/vacuum.c @@ -78,6 +78,7 @@ int vacuum_failsafe_age; int vacuum_multixact_failsafe_age; double vacuum_max_eager_freeze_failure_rate; bool track_cost_delay_timing; +bool vacuum_truncate; /* * Variables for cost-based vacuum delay. The defaults differ between @@ -2198,13 +2199,21 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params, ((StdRdOptions *) rel->rd_options)->vacuum_max_eager_freeze_failure_rate; /* - * Set truncate option based on truncate reloption if it wasn't specified - * in VACUUM command, or when running in an autovacuum worker + * Set truncate option based on truncate reloption or GUC if it wasn't + * specified in VACUUM command, or when running in an autovacuum worker */ if (params->truncate == VACOPTVALUE_UNSPECIFIED) { - if (rel->rd_options == NULL || - ((StdRdOptions *) rel->rd_options)->vacuum_truncate) + StdRdOptions *opts = (StdRdOptions *) rel->rd_options; + + if (opts && opts->vacuum_truncate_set) + { + if (opts->vacuum_truncate) + params->truncate = VACOPTVALUE_ENABLED; + else + params->truncate = VACOPTVALUE_DISABLED; + } + else if (vacuum_truncate) params->truncate = VACOPTVALUE_ENABLED; else params->truncate = VACOPTVALUE_DISABLED; -- cgit v1.2.3