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commit    2f70871c2bc18d103d5dd25ff9d91e0da29412ee
Author:   Michael Paquier <michael@paquier.xyz>
Date:     Thu Feb 20 04:55:00 2025 +0000
First released in: 18.0

    doc: Recommend pg_stat_io rather than pg_stat_wal in WAL configuration
    
    Since a051e71e28a1, pg_stat_io is able to track statistics for the WAL
    activity, providing an equivalent of pg_stat_wal with more granularity
    for the fsyncs/writes counts and timings, as the data is split across
    backend types.
    
    This commit now recommends pg_stat_io rather than pg_stat_wal in the
    section "WAL configuration", some of the latter's attributes being
    candidate for removal in a follow-up commit.
    
    Extracted from a larger patch by the same author.
    
    Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
    Discussion: https://postgr.es/m/Z7RkQ0EfYaqqjgz/@ip-10-97-1-34.eu-west-3.compute.internal


 doc/src/sgml/wal.sgml | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/doc/src/sgml/wal.sgml b/doc/src/sgml/wal.sgml
index b908720adea..4c0bf710dda 100644
--- a/doc/src/sgml/wal.sgml
+++ b/doc/src/sgml/wal.sgml
@@ -810,11 +810,12 @@
   <para>
    There are two internal functions to write WAL data to disk:
    <function>XLogWrite</function> and <function>issue_xlog_fsync</function>.
-   When <xref linkend="guc-track-wal-io-timing"/> is enabled, the total
+   When <xref linkend="guc-track-io-timing"/> is enabled, the total
    amounts of time <function>XLogWrite</function> writes and
    <function>issue_xlog_fsync</function> syncs WAL data to disk are counted as
-   <literal>wal_write_time</literal> and <literal>wal_sync_time</literal> in
-   <xref linkend="pg-stat-wal-view"/>, respectively.
+   <varname>write_time</varname> and <varname>sync_time</varname> in
+   <xref linkend="pg-stat-io-view"/> for the <varname>object</varname>
+   <literal>wal</literal>, respectively.
    <function>XLogWrite</function> is normally called by
    <function>XLogInsertRecord</function> (when there is no space for the new
    record in WAL buffers), <function>XLogFlush</function> and the WAL writer,
@@ -829,11 +830,12 @@
    <literal>fsync</literal>, or <literal>fsync_writethrough</literal>,
    the write operation moves WAL buffers to kernel cache and
    <function>issue_xlog_fsync</function> syncs them to disk. Regardless
-   of the setting of <varname>track_wal_io_timing</varname>, the number
+   of the setting of <varname>track_io_timing</varname>, the number
    of times <function>XLogWrite</function> writes and
    <function>issue_xlog_fsync</function> syncs WAL data to disk are also
-   counted as <literal>wal_write</literal> and <literal>wal_sync</literal>
-   in <structname>pg_stat_wal</structname>, respectively.
+   counted as <varname>writes</varname> and <varname>fsyncs</varname>
+   in <structname>pg_stat_io</structname> for the <varname>object</varname>
+   <literal>wal</literal>, respectively.
   </para>
 
   <para>


[parent: 71f17823ba01]