Thread: pgsql: Change default of pg_stat_statements.track_planning to off.
Change default of pg_stat_statements.track_planning to off. Since v13 pg_stat_statements is allowed to track the planning time of statements when track_planning option is enabled. Its default was on. But this feature could cause more terrible spinlock contentions in pg_stat_statements. As a result of this, Robins Tharakan reported that v13 beta1 showed ~45% performance drop at high DB connection counts (when compared with v12.3) during fully-cached SELECT-only test using pgbench. To avoid this performance regression by the default setting, this commit changes default of pg_stat_statements.track_planning to off. Back-patch to v13 where pg_stat_statements.track_planning was introduced. Reported-by: Robins Tharakan Author: Fujii Masao Reviewed-by: Julien Rouhaud Discussion: https://postgr.es/m/2895b53b033c47ccb22972b589050dd9@EX13D05UWC001.ant.amazon.com Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/8d459762b10372e48845a49b305f4e1e165fe173 Modified Files -------------- .../pg_stat_statements/expected/pg_stat_statements.out | 1 + contrib/pg_stat_statements/pg_stat_statements.c | 2 +- contrib/pg_stat_statements/sql/pg_stat_statements.sql | 1 + doc/src/sgml/pgstatstatements.sgml | 17 +++++++++++++++-- 4 files changed, 18 insertions(+), 3 deletions(-)