Update documentation to mention that autovacuum also does analyze so we

don't need to recommend nightly analyzes anymore unless autovacuum is off.
This commit is contained in:
Bruce Momjian 2007-09-14 13:43:03 +00:00
parent fc79628641
commit 13e26073bd

View File

@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.80 2007/09/14 02:43:18 momjian Exp $ --> <!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.81 2007/09/14 13:43:03 momjian Exp $ -->
<chapter id="maintenance"> <chapter id="maintenance">
<title>Routine Database Maintenance Tasks</title> <title>Routine Database Maintenance Tasks</title>
@ -262,12 +262,19 @@
</tip> </tip>
<para> <para>
Recommended practice for most sites is to schedule a database-wide Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table
<command>ANALYZE</> once a day at a low-usage time of day; this can activity and performs <command>ANALYZE</command>s when necessary. This
usefully be combined with a nightly <command>VACUUM</>. However, eliminates the need for administrators to manually schedule
sites with relatively slowly changing table statistics might find that <command>ANALYZE</command>.
this is overkill, and that less-frequent <command>ANALYZE</> runs </para>
are sufficient.
<para>
For those not using autovacuum, one approach is to schedule a
database-wide <command>ANALYZE</> once a day at a low-usage time of
day; this can usefully be combined with a nightly <command>VACUUM</>.
However, sites with relatively slowly changing table statistics might
find that this is overkill, and that less-frequent <command>ANALYZE</>
runs are sufficient.
</para> </para>
</sect2> </sect2>