↑↓ select↵ open⌫ change scopeOpen full search

PG.CENTER connects PostgreSQL documentation, reference, and ecosystem knowledge. Maintained by Pigsty.

Wiki / Configuration Parameters

vacuum_multixact_freeze_table_age

VACUUM performs an aggressive scan if the table's pg_class.relminmxid field has reached the age specified by this setting. An aggressive scan differs from a regular VACUUM in that it visits every page that might contain unfrozen XIDs or MXIDs, not just those that might contain dead tuples. The default is 150 million multixacts. Although users can set this value anywhere from zero to two billion, VACUUM will silently limit the effective value to 95% of autovacuum_multixact_freeze_max_age, so that a periodic manual VACUUM has a chance to run before an anti-wraparound is launched for the table. For more information see Section 24.1.5.1.

English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.

Reading PG 18·Select a recorded version

boot val
150000000
category
Vacuuming / Freezing
context
user
doc same as
Unknown
documented
true
enumvals
Unknown
extra desc
Unknown
lang
en
max val
2000000000
metadata version
18
min val
0
name
vacuum_multixact_freeze_table_age
short desc
Multixact age at which VACUUM should scan whole table to freeze tuples.
source
pg-settings-source-snapshot
unit
Unknown
vartype
integer

Definition PG 18

VACUUM performs an aggressive scan if the table's pg_class.relminmxid field has reached the age specified by this setting. An aggressive scan differs from a regular VACUUM in that it visits every page that might contain unfrozen XIDs or MXIDs, not just those that might contain dead tuples. The default is 150 million multixacts. Although users can set this value anywhere from zero to two billion, VACUUM will silently limit the effective value to 95% of autovacuum_multixact_freeze_max_age, so that a periodic manual VACUUM has a chance to run before an anti-wraparound is launched for the table. For more information see Section 24.1.5.1.

Compare versions

Complete source facts

doc html

<p>
<code class="command">VACUUM</code> performs an aggressive scan if the table's
         <code class="structname">pg_class</code>.<code class="structfield">relminmxid</code> field has reached
         the age specified by this setting.  An aggressive scan differs from
         a regular <code class="command">VACUUM</code> in that it visits every page that might
         contain unfrozen XIDs or MXIDs, not just those that might contain dead
         tuples.  The default is 150 million multixacts.
         Although users can set this value anywhere from zero to two billion,
         <code class="command">VACUUM</code> will silently limit the effective value to 95% of
         <a class="xref" href="/docs/18/runtime-config-vacuum.html#GUC-AUTOVACUUM-MULTIXACT-FREEZE-MAX-AGE">autovacuum_multixact_freeze_max_age</a>, so that a
         periodic manual <code class="command">VACUUM</code> has a chance to run before an
         anti-wraparound is launched for the table.
         For more information see <a class="xref" href="/docs/18/routine-vacuuming.html#VACUUM-FOR-MULTIXACT-WRAPAROUND" title="24.1.5.1. Multixacts and Wraparound">Section 24.1.5.1</a>.
        </p>

documentation revision

{"inputs":[{"file":"runtime-config-vacuum.html","kind":"same-version-reviewed-manual","locale":"en","sha256":"599d3819c5fa60f160ba633df604ee9afd85549ffad2ae2fb0c3132a00d47417","version":"18.7"},{"file":"runtime-config-vacuum.html","kind":"same-version-reviewed-manual","locale":"zh-Hans","sha256":"b835e4b6c446cfdaf673750aba29ba28fc55ef6cc0c531558c1e394fdc05a140","version":"18.7"}],"release":"18.7","runtime_remeasured":false,"source_revision":"pgdoc:b9f0e7232f60f380d642ac9b99226606c254b552"}

Source references

Full definition and evidence JSON

Definition sources

center · PostgreSQL 18 · wiki-repair-20261023:e2e9a26d829957cd969d1c3f313b56bbb5e5005094d2742dc808d83c201b6921

Text language: en · wiki-repair-20261023:e2e9a26d829957cd969d1c3f313b56bbb5e5005094d2742dc808d83c201b6921