diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 24 | ||||
| -rw-r--r-- | doc/src/sgml/ref/analyze.sgml | 22 | ||||
| -rw-r--r-- | doc/src/sgml/ref/vacuum.sgml | 3 |
3 files changed, 35 insertions, 14 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index a7b740af1a7..33b86818ca2 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.83 2007/10/06 17:45:49 alvherre Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.84 2007/10/07 01:16:42 alvherre Exp $ --> <chapter id="maintenance"> <title>Routine Database Maintenance Tasks</title> @@ -59,9 +59,9 @@ </indexterm> <para> - <productname>PostgreSQL</productname>'s <command>VACUUM</> (<xref - linkend="sql-vacuum">) command has to run on a regular basis for several - reasons: + <productname>PostgreSQL</productname>'s + <xref linkend="sql-vacuum" endterm="sql-vacuum-title"> command has to run on + a regular basis for several reasons: <orderedlist> <listitem> @@ -96,7 +96,8 @@ </para> <para> - Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table + Fortunately, <xref linkend="autovacuum" endterm="autovacuum-title"> + monitors table activity and performs <command>VACUUM</command>s when necessary. Autovacuum works dynamically so it is often better administration-scheduled vacuuming. @@ -150,7 +151,8 @@ </para> <para> - Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table + Fortunately, <xref linkend="autovacuum" endterm="autovacuum-title"> + monitors table activity and performs <command>VACUUM</command>s when necessary. This eliminates the need for administrators to worry about disk space recovery in all but the most unusual cases. @@ -218,7 +220,8 @@ The <productname>PostgreSQL</productname> query planner relies on statistical information about the contents of tables in order to generate good plans for queries. These statistics are gathered by - the <command>ANALYZE</> command, which can be invoked by itself or + the <xref linkend="sql-analyze" endterm="sql-analyze-title"> command, + which can be invoked by itself or as an optional step in <command>VACUUM</>. It is important to have reasonably accurate statistics, otherwise poor choices of plans might degrade database performance. @@ -262,7 +265,8 @@ </tip> <para> - Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table + Fortunately, <xref linkend="autovacuum" endterm="autovacuum-title"> + monitors table activity and performs <command>ANALYZE</command>s when necessary. This eliminates the need for administrators to manually schedule <command>ANALYZE</command>. @@ -341,8 +345,8 @@ when it was last vacuumed. If it were to go unvacuumed for longer than that, data loss could result. To ensure that this does not - happen, the <firstterm>autovacuum</> facility described in - <xref linkend="autovacuum"> is invoked on any table + happen, <xref linkend="autovacuum" endterm="autovacuum-title"> + is invoked on any table that might contain XIDs older than the age specified by the configuration parameter <xref linkend="guc-autovacuum-freeze-max-age">. (This will happen diff --git a/doc/src/sgml/ref/analyze.sgml b/doc/src/sgml/ref/analyze.sgml index bb293af03cc..f84999b03fe 100644 --- a/doc/src/sgml/ref/analyze.sgml +++ b/doc/src/sgml/ref/analyze.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/ref/analyze.sgml,v 1.22 2007/05/15 19:13:55 neilc Exp $ +$PostgreSQL: pgsql/doc/src/sgml/ref/analyze.sgml,v 1.23 2007/10/07 01:16:42 alvherre Exp $ PostgreSQL documentation --> @@ -92,7 +92,12 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ ( <re <title>Notes</title> <para> - It is a good idea to run <command>ANALYZE</command> periodically, or + In the default <productname>PostgreSQL</productname> configuration, + <xref linkend="autovacuum" endterm="autovacuum-title"> + takes care of automatic analyzing of tables when they are first loaded + with data, and as they change throughout regular operation. + When autovacuum is disabled, + it is a good idea to run <command>ANALYZE</command> periodically, or just after making major changes in the contents of a table. Accurate statistics will help the planner to choose the most appropriate query plan, and thereby improve the speed of query processing. A common @@ -101,7 +106,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ ( <re </para> <para> - Unlike <command>VACUUM FULL</command>, <command>ANALYZE</command> + <command>ANALYZE</command> requires only a read lock on the target table, so it can run in parallel with other activity on the table. </para> @@ -168,4 +173,15 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ ( <re There is no <command>ANALYZE</command> statement in the SQL standard. </para> </refsect1> + + <refsect1> + <title>See Also</title> + + <simplelist type="inline"> + <member><xref linkend="sql-vacuum" endterm="sql-vacuum-title"></member> + <member><xref linkend="app-vacuumdb" endterm="app-vacuumdb-title"></member> + <member><xref linkend="runtime-config-resource-vacuum-cost" endterm="runtime-config-resource-vacuum-cost-title"></member> + <member><xref linkend="autovacuum" endterm="autovacuum-title"></member> + </simplelist> + </refsect1> </refentry> diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml index 60bd2ff73e7..013b75f0927 100644 --- a/doc/src/sgml/ref/vacuum.sgml +++ b/doc/src/sgml/ref/vacuum.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.48 2007/05/30 19:45:01 momjian Exp $ +$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.49 2007/10/07 01:16:42 alvherre Exp $ PostgreSQL documentation --> @@ -242,6 +242,7 @@ VACUUM <simplelist type="inline"> <member><xref linkend="app-vacuumdb" endterm="app-vacuumdb-title"></member> <member><xref linkend="runtime-config-resource-vacuum-cost" endterm="runtime-config-resource-vacuum-cost-title"></member> + <member><xref linkend="autovacuum" endterm="autovacuum-title"></member> </simplelist> </refsect1> </refentry> |