From 05ce730978c9ee2d48599ffeaada98f69bd3be42 Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Fri, 27 Oct 2023 21:24:55 -0400 Subject: [PATCH] doc: improve text around consistency of statistics values Discussion: https://postgr.es/m/CAKFQuwZ4CXtTyR19vFbd9WwmW-4BvgAenmF2CfUpx0LWwRPGYg@mail.gmail.com Author: David G. Johnston Backpatch-through: master --- doc/src/sgml/maintenance.sgml | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index 9389eef973..2bfa05b8bc 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -924,10 +924,9 @@ vacuum insert threshold = vacuum base insert threshold + vacuum insert scale fac as this may allow tuples to be frozen by earlier vacuums. The number of obsolete tuples and the number of inserted tuples are obtained from the cumulative statistics system; - it is a semi-accurate count updated by each UPDATE, - DELETE and INSERT operation. (It is - only semi-accurate because some information might be lost under heavy - load.) If the relfrozenxid value of the table + it is an eventually-consistent count updated by each UPDATE, + DELETE and INSERT operation. + If the relfrozenxid value of the table is more than vacuum_freeze_table_age transactions old, an aggressive vacuum is performed to freeze old tuples and advance relfrozenxid; otherwise, only pages that have been modified