postgres/doc/src/sgml/ref/pgarchivecleanup.sgml

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doc/src/sgml/ref/pgarchivecleanup.sgml
PostgreSQL documentation
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<refentry id="pgarchivecleanup">
 <indexterm zone="pgarchivecleanup">
  <primary>pg_archivecleanup</primary>
 </indexterm>

 <refmeta>
  <refentrytitle><application>pg_archivecleanup</application></refentrytitle>
  <manvolnum>1</manvolnum>
  <refmiscinfo>Application</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>pg_archivecleanup</refname>
  <refpurpose>clean up <productname>PostgreSQL</productname> WAL archive files</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
  <cmdsynopsis>
   <command>pg_archivecleanup</command>
   <arg rep="repeat"><replaceable>option</replaceable></arg>
   <arg choice="plain"><replaceable>archivelocation</replaceable></arg>
   <arg choice="plain"><replaceable>oldestkeptwalfile</replaceable></arg>
  </cmdsynopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

 <para>
  <application>pg_archivecleanup</application> is designed to be used as an
  <literal>archive_cleanup_command</literal> to clean up WAL file archives when
  running as a standby server (see <xref linkend="warm-standby"/>).
  <application>pg_archivecleanup</application> can also be used as a standalone program to
  clean WAL file archives.
 </para>

  <para>
   To configure a standby
   server to use <application>pg_archivecleanup</application>, put this into its
   <filename>postgresql.conf</filename> configuration file:
<programlisting>
archive_cleanup_command = 'pg_archivecleanup <replaceable>archivelocation</replaceable> %r'
</programlisting>
   where <replaceable>archivelocation</replaceable> is the directory from which WAL segment
   files should be removed.
  </para>
  <para>
   When used within <xref linkend="guc-archive-cleanup-command"/>, all WAL files
   logically preceding the value of the <literal>%r</literal> argument will be removed
   from <replaceable>archivelocation</replaceable>. This minimizes the number of files
   that need to be retained, while preserving crash-restart capability.  Use of
   this parameter is appropriate if the <replaceable>archivelocation</replaceable> is a
   transient staging area for this particular standby server, but
   <emphasis>not</emphasis> when the <replaceable>archivelocation</replaceable> is intended as a
   long-term WAL archive area, or when multiple standby servers are recovering
   from the same archive location.
  </para>
  <para>
   When used as a standalone program all WAL files logically preceding the
   <replaceable>oldestkeptwalfile</replaceable> will be removed from <replaceable>archivelocation</replaceable>.
   In this mode, if you specify a <filename>.partial</filename> or <filename>.backup</filename>
   file name, then only the file prefix will be used as the
   <replaceable>oldestkeptwalfile</replaceable>. This treatment of <filename>.backup</filename>
   file name allows you to remove
   all WAL files archived prior to a specific base backup without error.
   For example, the following example will remove all files older than
   WAL file name <filename>000000010000003700000010</filename>:
<programlisting>
pg_archivecleanup -d archive 000000010000003700000010.00000020.backup

pg_archivecleanup:  keep WAL file "archive/000000010000003700000010" and later
pg_archivecleanup:  removing file "archive/00000001000000370000000F"
pg_archivecleanup:  removing file "archive/00000001000000370000000E"
</programlisting>
  </para>
  <para>
   <application>pg_archivecleanup</application> assumes that
   <replaceable>archivelocation</replaceable> is a directory readable and writable by the
   server-owning user.
  </para>
 </refsect1>

 <refsect1>
  <title>Options</title>

   <para>
    <application>pg_archivecleanup</application> accepts the following command-line arguments:

    <variablelist>

     <varlistentry>
      <term><option>-b</option></term>
      <term><option>--clean-backup-history</option></term>
      <listitem>
       <para>
         Remove backup history files as well.
         See <xref linkend="backup-base-backup"/> for details about backup
         history files.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-d</option></term>
      <term><option>--debug</option></term>
      <listitem>
       <para>
        Print lots of debug logging output on <filename>stderr</filename>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-n</option></term>
      <term><option>--dry-run</option></term>
      <listitem>
       <para>
        Print the names of the files that would have been removed on <filename>stdout</filename> (performs a dry run).
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-V</option></term>
      <term><option>--version</option></term>
      <listitem>
       <para>
        Print the <application>pg_archivecleanup</application> version and exit.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-x <replaceable class="parameter">extension</replaceable></option></term>
      <term><option>--strip-extension=<replaceable class="parameter">extension</replaceable></option></term>
      <listitem>
       <para>
        Provide an extension
        that will be stripped from all file names before deciding if they
        should be deleted.  This is typically useful for cleaning up archives
        that have been compressed during storage, and therefore have had an
        extension added by the compression program.  For example: <literal>-x
        .gz</literal>.
       </para>

      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-?</option></term>
      <term><option>--help</option></term>
      <listitem>
       <para>
        Show help about <application>pg_archivecleanup</application> command line
        arguments, and exit.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
   </para>
 </refsect1>

 <refsect1>
  <title>Environment</title>

  <para>
   The environment variable <envar>PG_COLOR</envar> specifies whether to use
   color in diagnostic messages. Possible values are
   <literal>always</literal>, <literal>auto</literal> and
   <literal>never</literal>.
  </para>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   <application>pg_archivecleanup</application> is designed to work with
   <productname>PostgreSQL</productname> 8.0 and later when used as a standalone utility,
   or with <productname>PostgreSQL</productname> 9.0 and later when used as an
   archive cleanup command.
  </para>

  <para>
   <application>pg_archivecleanup</application> is written in C and has an
   easy-to-modify source code, with specifically designated sections to modify
   for your own needs
  </para>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>On Linux or Unix systems, you might use:
<programlisting>
archive_cleanup_command = 'pg_archivecleanup -d /mnt/standby/archive %r 2>>cleanup.log'
</programlisting>
   where the archive directory is physically located on the standby server,
   so that the <varname>archive_command</varname> is accessing it across NFS,
   but the files are local to the standby.
   This will:
  </para>
  <itemizedlist>
   <listitem>
    <para>
     produce debugging output in <filename>cleanup.log</filename>
    </para>
   </listitem>
   <listitem>
    <para>
     remove no-longer-needed files from the archive directory
    </para>
   </listitem>
  </itemizedlist>
 </refsect1>

</refentry>