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-$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.36 2004/12/02 19:28:48 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.37 2005/07/30 15:45:49 momjian Exp $
PostgreSQL documentation
-->
to occupy less disk space. <command>VACUUM FULL</command> will usually
shrink the table more than a plain <command>VACUUM</command> would.
</para>
+
+ <para>
+ During <command>VACUUM</command> execution, there can be a substantial
+ increase in I/O traffic, which cause poor performance for other active
+ sessions. Therefore, it is sometimes advisable to use
+ the cost-based vacuum delay feature. See <xref
+ linkend="runtime" endterm="runtime-config-resource-vacuum-cost"> for more
+ details.
+ </para>
</refsect1>
<refsect1>
<simplelist type="inline">
<member><xref linkend="app-vacuumdb" endterm="app-vacuumdb-title"></member>
+ <member><xref linkend="runtime" endterm="runtime-config-resource-vacuum-cost"></member>
</simplelist>
</refsect1>
</refentry>