diff options
| author | Fujii Masao <fujii@postgresql.org> | 2025-10-17 14:03:42 +0900 |
|---|---|---|
| committer | Fujii Masao <fujii@postgresql.org> | 2025-10-17 14:03:42 +0900 |
| commit | e64aa1a39d4b8a9502be8ed8dfd67efd6f6acf28 (patch) | |
| tree | 84b784924823f12f873dbdb9f2f0b387e03dbe55 | |
| parent | d1b80a31ed6dc185108af74f363bd6baad98104f (diff) | |
doc: Clarify when backend_xmin in pg_stat_replication can be NULL.
Improve the documentation of pg_stat_replication to explain when
the backend_xmin column becomes NULL. This happens when
a replication slot is used (the xmin is then shown in pg_replication_slots)
or when hot_standby_feedback is disabled.
Author: Renzo Dani <arons7@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CA+XOKQAMXzskpdUmj2sg03_5fmiXc2Gs0r3TX1_rmcFcqh+=xQ@mail.gmail.com
| -rw-r--r-- | doc/src/sgml/monitoring.sgml | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index dc4fc29466d..d5f0fb7ba7c 100644 --- a/doc/src/sgml/monitoring.sgml +++ b/doc/src/sgml/monitoring.sgml @@ -1287,6 +1287,10 @@ description | Waiting for a newly initialized WAL file to reach durable storage <para> This standby's <literal>xmin</literal> horizon reported by <xref linkend="guc-hot-standby-feedback"/>. + This field will be null if a replication slot is used (in this case, + the standby's <literal>xmin</literal> is shown in + <link linkend="view-pg-replication-slots">pg_replication_slots</link>) + or if <varname>hot_standby_feedback</varname> is disabled. </para></entry> </row> |