From 00d1e88d36687ceae1be2317fac90e967941c085 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Thu, 31 Jan 2019 13:06:51 +0900
Subject: Add --min-xid-age and --min-mxid-age options to vacuumdb

These two new options can be used to improve the selectivity of
relations to vacuum or analyze even further depending on the age of
respectively their transaction ID or multixact ID, so as it is possible
to prioritize tables to prevent wraparound of one or the other.
Combined with --table, it is possible to target a subset of tables to
choose as potential processing targets.

Author: Nathan Bossart
Reviewed-by: Michael Paquier, Masahiko Sawada
Discussion: https://postgr.es/m/FFE5373C-E26A-495B-B5C8-911EC4A41C5E@amazon.com
---
 doc/src/sgml/ref/vacuumdb.sgml | 54 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

(limited to 'doc/src')

diff --git a/doc/src/sgml/ref/vacuumdb.sgml b/doc/src/sgml/ref/vacuumdb.sgml
index f304627802e..41c7f3df793 100644
--- a/doc/src/sgml/ref/vacuumdb.sgml
+++ b/doc/src/sgml/ref/vacuumdb.sgml
@@ -172,6 +172,60 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--min-mxid-age <replaceable class="parameter">mxid_age</replaceable></option></term>
+      <listitem>
+       <para>
+        Only execute the vacuum or analyze commands on tables with a multixact
+        ID age of at least <replaceable class="parameter">mxid_age</replaceable>.
+        This setting is useful for prioritizing tables to process to prevent
+        multixact ID wraparound (see
+        <xref linkend="vacuum-for-multixact-wraparound"/>).
+       </para>
+       <para>
+        For the purposes of this option, the multixact ID age of a relation is
+        the greatest of the ages of the main relation and its associated
+        <acronym>TOAST</acronym> table, if one exists.  Since the commands
+        issued by <application>vacuumdb</application> will also process the
+        <acronym>TOAST</acronym> table for the relation if necessary, it does
+        not need to be considered separately.
+       </para>
+       <note>
+        <para>
+         This option is only available for servers running
+         <productname>PostgreSQL</productname> 9.6 and later.
+        </para>
+       </note>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><option>--min-xid-age <replaceable class="parameter">xid_age</replaceable></option></term>
+      <listitem>
+       <para>
+        Only execute the vacuum or analyze commands on tables with a
+        transaction ID age of at least
+        <replaceable class="parameter">xid_age</replaceable>.  This setting
+        is useful for prioritizing tables to process to prevent transaction
+        ID wraparound (see <xref linkend="vacuum-for-wraparound"/>).
+       </para>
+       <para>
+        For the purposes of this option, the transaction ID age of a relation
+        is the greatest of the ages of the main relation and its associated
+        <acronym>TOAST</acronym> table, if one exists.  Since the commands
+        issued by <application>vacuumdb</application> will also process the
+        <acronym>TOAST</acronym> table for the relation if necessary, it does
+        not need to be considered separately.
+       </para>
+       <note>
+        <para>
+         This option is only available for servers running
+         <productname>PostgreSQL</productname> 9.6 and later.
+        </para>
+       </note>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>-q</option></term>
       <term><option>--quiet</option></term>
-- 
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