diff options
| author | John Naylor <john.naylor@postgresql.org> | 2025-03-07 10:22:56 +0700 |
|---|---|---|
| committer | John Naylor <john.naylor@postgresql.org> | 2025-03-07 10:24:06 +0700 |
| commit | 5c8dcf9483349f39ee8da965c3acd3a61cf242fe (patch) | |
| tree | 39271fd7e2ceedc1d2903a2b9449a8d2adad2f7e | |
| parent | 9094eb25b7d956307677f9ff26c8a3fc900ca1c0 (diff) | |
Doc: correct aggressive vacuum threshold for multixact members storage
The threshold is two billion members, which was interpreted as 2GB
in the documentation. Fix to reflect that each member takes up five
bytes, which translates to about 10GB. This is not exact, because of
page boundaries. While at it, mention the maximum size 20GB.
This has been wrong since commit c552e171d16e, so backpatch to
version 14.
Author: Alex Friedman <alexf01@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CACbFw60UOk6fCC02KsyT3OfU9Dnuq5roYxdw2aFisiN_p1L0bg@mail.gmail.com
Backpatch-through: 14
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index 0be90bdc7ef..89040942be2 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -793,10 +793,11 @@ HINT: Execute a database-wide VACUUM in that database. As a safety device, an aggressive vacuum scan will occur for any table whose multixact-age is greater than <xref linkend="guc-autovacuum-multixact-freeze-max-age"/>. Also, if the - storage occupied by multixacts members exceeds 2GB, aggressive vacuum + storage occupied by multixacts members exceeds about 10GB, aggressive vacuum scans will occur more often for all tables, starting with those that have the oldest multixact-age. Both of these kinds of aggressive - scans will occur even if autovacuum is nominally disabled. + scans will occur even if autovacuum is nominally disabled. The members storage + area can grow up to about 20GB before reaching wraparound. </para> <para> |