DOC: fix renaming of pg_clog to pg_xact

Author: Liudmila Mantrova

doc/src/sgml/config.sgml

@@ -5938,7 +5938,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
        <para>
         Note that even when this parameter is disabled, the system
         will launch autovacuum processes if necessary to shrink
-        <literal>pg_clog</> and <literal>pg_multixact</>.  See <xref
+        <literal>pg_xact</> and <literal>pg_multixact</>.  See <xref
         linkend="vacuum-for-wraparound"> for more information.
        </para>
       </listitem>
@@ -6092,7 +6092,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         Specifies the maximum age (in transactions) that a table's
         <structname>pg_class</>.<structfield>relfrozenxid</> field can
         attain before a <command>VACUUM</> operation is forced
-        to shrink <literal>pg_clog</>.
+        to shrink <literal>pg_xact</>.
         Note that the system will launch autovacuum processes for this purpose
         even when autovacuum is otherwise disabled.
        </para>
@@ -6626,7 +6626,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         will silently limit the effective value to 95% of
         <xref linkend="guc-autovacuum-freeze-max-age">, so that a
         periodical manual <command>VACUUM</> has a chance to run before an
-        autovacuum to shrink <literal>pg_clog</> and <literal>pg_multixact</>
+        autovacuum to shrink <literal>pg_xact</> and <literal>pg_multixact</>
         is launched for the table. For more information see
         <xref linkend="vacuum-for-wraparound">.
        </para>
@@ -6673,7 +6673,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         <command>VACUUM</> will silently limit the effective value to 95% of
         <xref linkend="guc-autovacuum-multixact-freeze-max-age">, so that a
         periodical manual <command>VACUUM</> has a chance to run before an
-        autovacuum to shrink <literal>pg_clog</> and <literal>pg_multixact</>
+        autovacuum to shrink <literal>pg_xact</> and <literal>pg_multixact</>
         is launched for the table.
         For more information see <xref linkend="vacuum-for-multixact-wraparound">.
        </para>

doc/src/sgml/maintenance.sgml

@@ -108,7 +108,7 @@
      </listitem>
 
      <listitem>
-      <simpara>To shrink <literal>pg_clog</> and
+      <simpara>To shrink <literal>pg_xact</> and
       <literal>pg_multixact</>.</simpara>
      </listitem>
     </orderedlist>
@@ -375,7 +375,7 @@
   </sect2>
 
   <sect2 id="vacuum-for-wraparound">
-   <title>Forced shrinking <literal>pg_clog</> and <literal>pg_multixact</></title>
+   <title>Forced shrinking <literal>pg_xact</> and <literal>pg_multixact</></title>
 
    <indexterm zone="vacuum-for-wraparound">
     <primary>transaction ID</primary>
@@ -437,9 +437,9 @@
     Freezing data by <command>VACUUM</> is not needed anymore for preventing
     wraparound, since page-level freeze happens "on the fly".  However,
     freezing data by <command>VACUUM</> is still needed for shrink
-    <literal>pg_clog</> and <literal>pg_multixact</>.  For historical reasons,
+    <literal>pg_xact</> and <literal>pg_multixact</>.  For historical reasons,
     wording "autovacuum to prevent wraparound" is preserved for forced
-    autovacuum for shrink <literal>pg_clog</> and <literal>pg_multixact</>.
+    autovacuum for shrink <literal>pg_xact</> and <literal>pg_multixact</>.
    </para>
 
    <note>
@@ -517,15 +517,15 @@
     <varname>autovacuum_freeze_max_age</>; a setting higher than that will be
     capped to the maximum. A value higher than
     <varname>autovacuum_freeze_max_age</> wouldn't make sense because an
-    autovacuum to shrink <literal>pg_clog</> and <literal>pg_multixact</>
+    autovacuum to shrink <literal>pg_xact</> and <literal>pg_multixact</>
     would be triggered at that point anyway, and
     the 0.95 multiplier leaves some breathing room to run a manual
     <command>VACUUM</> before that happens.  As a rule of thumb,
     <command>vacuum_freeze_table_age</> should be set to a value somewhat
     below <varname>autovacuum_freeze_max_age</>, leaving enough gap so that
     a regularly scheduled <command>VACUUM</> or an autovacuum triggered by
     normal delete and update activity is run in that window.  Setting it too
-    close could lead to autovacuums to shrink <literal>pg_clog</> and
+    close could lead to autovacuums to shrink <literal>pg_xact</> and
     <literal>pg_multixact</>, even though the table
     was recently vacuumed to reclaim space, whereas lower values lead to more
     frequent aggressive vacuuming.

doc/src/sgml/ref/create_table.sgml

@@ -1225,10 +1225,10 @@ FROM ( { <replaceable class="PARAMETER">numeric_literal</replaceable> | <replace
      and/or <command>ANALYZE</> operations on this table following the rules
      discussed in <xref linkend="autovacuum">.
      If false, this table will not be autovacuumed, except to shrink
-     <literal>pg_clog</> and <literal>pg_multixact</>.
+     <literal>pg_xact</> and <literal>pg_multixact</>.
      See <xref linkend="vacuum-for-wraparound"> for more about that.
      Note that the autovacuum daemon does not run at all (except to shrink
-     <literal>pg_clog</> and <literal>pg_multixact</>) if the
+     <literal>pg_xact</> and <literal>pg_multixact</>) if the
      <xref linkend="guc-autovacuum">
      parameter is false; setting individual tables' storage parameters does
      not override that.  Therefore there is seldom much point in explicitly