From 44fe6ceb51f001689048c19ea3ea53fbf2572581 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Thu, 27 Mar 2025 10:20:41 +0900 Subject: [PATCH] doc: Correct description of values used in FSM for indexes The implementation of FSM for indexes is simpler than heap, where 0 is used to track if a page is in-use and (BLCKSZ - 1) if a page is free. One comment in indexfsm.c and one description in the documentation of pg_freespacemap were incorrect about that. Author: Alex Friedman Discussion: https://postgr.es/m/71eef655-c192-453f-ac45-2772fec2cb04@gmail.com Backpatch-through: 13 --- doc/src/sgml/pgfreespacemap.sgml | 2 +- src/backend/storage/freespace/indexfsm.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/pgfreespacemap.sgml b/doc/src/sgml/pgfreespacemap.sgml index 829ad60f32f..3774a9f8c6b 100644 --- a/doc/src/sgml/pgfreespacemap.sgml +++ b/doc/src/sgml/pgfreespacemap.sgml @@ -67,7 +67,7 @@ For indexes, what is tracked is entirely-unused pages, rather than free space within pages. Therefore, the values are not meaningful, just - whether a page is full or empty. + whether a page is in-use or empty. diff --git a/src/backend/storage/freespace/indexfsm.c b/src/backend/storage/freespace/indexfsm.c index 1fc263892a7..614261e4e22 100644 --- a/src/backend/storage/freespace/indexfsm.c +++ b/src/backend/storage/freespace/indexfsm.c @@ -16,7 +16,7 @@ * This is similar to the FSM used for heap, in freespace.c, but instead * of tracking the amount of free space on pages, we only track whether * pages are completely free or in-use. We use the same FSM implementation - * as for heaps, using BLCKSZ - 1 to denote used pages, and 0 for unused. + * as for heaps, using 0 to denote used pages, and (BLCKSZ - 1) for unused. * *------------------------------------------------------------------------- */