mirrors/postgres
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Use "dead" rather than "expired" for vacuumable rows.

Browse Source
This commit is contained in:
Bruce Momjian 2006-12-27 14:55:17 +00:00
parent 0cbc5b1ed4
commit 4f1e49119e
2 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
doc/src/sgml/maintenance.sgml
View File

@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.64 2006/11/05 22:42:07 tgl Exp $ --> <!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.65 2006/12/27 14:55:17 momjian Exp $ -->
<chapter id="maintenance"> <chapter id="maintenance">
<title>Routine Database Maintenance Tasks</title> <title>Routine Database Maintenance Tasks</title>
@ -142,9 +142,9 @@
<para> <para>
There are two variants of the <command>VACUUM</command> There are two variants of the <command>VACUUM</command>
command. The first form, known as <quote>lazy vacuum</quote> or command. The first form, known as <quote>lazy vacuum</quote> or
just <command>VACUUM</command>, marks expired data in tables and just <command>VACUUM</command>, marks dead data in tables and
indexes for future reuse; it does <emphasis>not</emphasis> attempt indexes for future reuse; it does <emphasis>not</emphasis> attempt
to reclaim the space used by this expired data unless the space is to reclaim the space used by this dead data unless the space is
at the end of the table and an exclusive table lock can be easily at the end of the table and an exclusive table lock can be easily
obtained. Unused space at the start or middle of the file does obtained. Unused space at the start or middle of the file does
not result in the file being shortened and space returned to the not result in the file being shortened and space returned to the
@ -155,7 +155,7 @@
<para> <para>
The second form is the <command>VACUUM FULL</command> The second form is the <command>VACUUM FULL</command>
command. This uses a more aggressive algorithm for reclaiming the command. This uses a more aggressive algorithm for reclaiming the
space consumed by expired row versions. Any space that is freed by space consumed by dead row versions. Any space that is freed by
<command>VACUUM FULL</command> is immediately returned to the <command>VACUUM FULL</command> is immediately returned to the
operating system. Unfortunately, this variant of the operating system. Unfortunately, this variant of the
<command>VACUUM</command> command acquires an exclusive lock on <command>VACUUM</command> command acquires an exclusive lock on

6
doc/src/sgml/ref/vacuum.sgml
View File

@ -1,5 +1,5 @@
<!-- <!--
$PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.44 2006/12/23 01:58:40 momjian Exp $ $PostgreSQL: pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.45 2006/12/27 14:55:17 momjian Exp $
PostgreSQL documentation PostgreSQL documentation
--> -->
@ -29,7 +29,7 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">
<title>Description</title> <title>Description</title>
<para> <para>
<command>VACUUM</command> reclaims storage occupied by expired tuples. <command>VACUUM</command> reclaims storage occupied by dead tuples.
In normal <productname>PostgreSQL</productname> operation, tuples that In normal <productname>PostgreSQL</productname> operation, tuples that
are deleted or obsoleted by an update are not physically removed from are deleted or obsoleted by an update are not physically removed from
their table; they remain present until a <command>VACUUM</command> is their table; they remain present until a <command>VACUUM</command> is
@ -152,7 +152,7 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">
<para> <para>
We recommend that active production databases be We recommend that active production databases be
vacuumed frequently (at least nightly), in order to vacuumed frequently (at least nightly), in order to
remove expired rows. After adding or deleting a large number remove dead rows. After adding or deleting a large number
of rows, it may be a good idea to issue a <command>VACUUM of rows, it may be a good idea to issue a <command>VACUUM
ANALYZE</command> command for the affected table. This will update the ANALYZE</command> command for the affected table. This will update the
system catalogs with system catalogs with