vacuum-index-cleanup-doc-rmh.patch

diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index 166078410c..2ce7a0cdbc 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -1344,6 +1344,21 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><literal>vacuum_index_cleanup</literal> (<type>boolean</type>)</term>
+    <listitem>
+     <para>
+     Enables or disables index cleanup when <command>VACUUM</command> is
+     run on this table.  The default value is <literal>true</literal>.
+     Disabling index cleanup can speed of <command>VACUUM</command> very
+     significantly, but may also lead to severely bloated indexes if table
+     modifications are frequent.  The <literal>INDEX_CLEANUP</literal>
+     parameter to <xref linkend="sql-vacuum"/>, if specified, overrides
+     the value of this option.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term><literal>autovacuum_vacuum_threshold</literal>, <literal>toast.autovacuum_vacuum_threshold</literal> (<type>integer</type>)</term>
     <listitem>
diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml
index 906d0c2ad7..13b9735c22 100644
--- a/doc/src/sgml/ref/vacuum.sgml
+++ b/doc/src/sgml/ref/vacuum.sgml
@@ -32,6 +32,7 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ <replaceable class="paramet
     ANALYZE [ <replaceable class="parameter">boolean</replaceable> ]
     DISABLE_PAGE_SKIPPING [ <replaceable class="parameter">boolean</replaceable> ]
     SKIP_LOCKED [ <replaceable class="parameter">boolean</replaceable> ]
+    INDEX_CLEANUP [ <replaceable class="parameter">boolean</replaceable> ]
 
 <phrase>and <replaceable class="parameter">table_and_columns</replaceable> is:</phrase>
 
@@ -181,6 +182,28 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ <replaceable class="paramet
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><literal>INDEX_CLEANUP</literal></term>
+    <listitem>
+     <para>
+      Specifies that <command>VACUUM</command> should attempt to remove
+      index entries pointing to dead tuples.  This is normally the desired
+      behavior and is the default unless the
+      <literal>vacuum_index_cleanup</literal> option has been set to false
+      for the table to be vacuumed.  Setting this option to false may be
+      useful when it is necessary to make vacuum run as quickly as possible,
+      for example to avoid imminent transaction ID wraparond
+      (see <xref linkend="vacuum-for-wraparound"/>).  However, if index
+      cleanup is not performed regularly, performance may suffer, because
+      as the table is modified, indexes will accumulate dead line pointers
+      and the table itself will accumulate dead line pointers that cannot be
+      removed until index cleanup is completed.  This option has no effect
+      when <literal>FULL</literal> is used or for tables that do not have
+      an index.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term><replaceable class="parameter">boolean</replaceable></term>
     <listitem>