diff options
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index 9389eef973d..2bfa05b8bc0 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -924,10 +924,9 @@ vacuum insert threshold = vacuum base insert threshold + vacuum insert scale fac <xref linkend="reloption-autovacuum-freeze-min-age"/> as this may allow tuples to be frozen by earlier vacuums. The number of obsolete tuples and the number of inserted tuples are obtained from the cumulative statistics system; - it is a semi-accurate count updated by each <command>UPDATE</command>, - <command>DELETE</command> and <command>INSERT</command> operation. (It is - only semi-accurate because some information might be lost under heavy - load.) If the <structfield>relfrozenxid</structfield> value of the table + it is an eventually-consistent count updated by each <command>UPDATE</command>, + <command>DELETE</command> and <command>INSERT</command> operation. + If the <structfield>relfrozenxid</structfield> value of the table is more than <varname>vacuum_freeze_table_age</varname> transactions old, an aggressive vacuum is performed to freeze old tuples and advance <structfield>relfrozenxid</structfield>; otherwise, only pages that have been modified |