diff options
Diffstat (limited to 'doc/src/sgml/maintenance.sgml')
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index 8764e0091ac..211ad03d954 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -628,6 +628,9 @@ HINT: Stop the postmaster and vacuum that database in single-user mode. Like transaction IDs, multixact IDs are implemented as a 32-bit counter and corresponding storage, all of which requires careful aging management, storage cleanup, and wraparound handling. + There is a separate storage area which holds the list of members in + each multixact, which also uses a 32-bit counter and which must also + be managed. </para> <para> @@ -656,7 +659,10 @@ HINT: Stop the postmaster and vacuum that database in single-user mode. As a safety device, a whole-table vacuum scan will occur for any table whose multixact-age is greater than <xref linkend="guc-autovacuum-multixact-freeze-max-age">. - This will occur even if autovacuum is nominally disabled. + This will occur even if autovacuum is nominally disabled. Whole-table + vacuum scans will also occur progressively for all tables, starting with + those that have the oldest multixact-age, if the amount of used member + storage space exceeds the amount 25% of the addressible storage space. </para> </sect3> </sect2> |