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* Lazy vacuum space reclaiming
@ 2005-10-14 18:51 Jim C. Nasby <[email protected]>
2005-12-07 05:36 ` Re: Lazy vacuum space reclaiming Bruce Momjian <[email protected]>
0 siblings, 1 reply; 2+ messages in thread
From: Jim C. Nasby @ 2005-10-14 18:51 UTC (permalink / raw)
To: pgsql-docs
From http://www.postgresql.org/docs/8.0/interactive/maintenance.html:
"The first form, known as "lazy vacuum" or just VACUUM, marks expired
data in tables and indexes for future reuse; it does not attempt to
reclaim the space used by this expired data immediately. Therefore, the
table file is not shortened, and any unused space in the file is not
returned to the operating system."
This isn't completely accurate, though I'm not sure what a good wording
would be. Maybe:
"The first form, known as "lazy vacuum" or just VACUUM, marks expired
data in tables and indexes for future reuse. It only reclaims expired
space from tables if it is at the end of the table, and no empty space
is reclaimed from indexes."
--
Jim C. Nasby, Sr. Engineering Consultant [email protected]
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: Lazy vacuum space reclaiming
2005-10-14 18:51 Lazy vacuum space reclaiming Jim C. Nasby <[email protected]>
@ 2005-12-07 05:36 ` Bruce Momjian <[email protected]>
0 siblings, 0 replies; 2+ messages in thread
From: Bruce Momjian @ 2005-12-07 05:36 UTC (permalink / raw)
To: Jim C. Nasby <[email protected]>; +Cc: pgsql-docs
Adjustment patch applied. Thanks.
---------------------------------------------------------------------------
Jim C. Nasby wrote:
> >From http://www.postgresql.org/docs/8.0/interactive/maintenance.html:
>
> "The first form, known as "lazy vacuum" or just VACUUM, marks expired
> data in tables and indexes for future reuse; it does not attempt to
> reclaim the space used by this expired data immediately. Therefore, the
> table file is not shortened, and any unused space in the file is not
> returned to the operating system."
>
> This isn't completely accurate, though I'm not sure what a good wording
> would be. Maybe:
>
> "The first form, known as "lazy vacuum" or just VACUUM, marks expired
> data in tables and indexes for future reuse. It only reclaims expired
> space from tables if it is at the end of the table, and no empty space
> is reclaimed from indexes."
> --
> Jim C. Nasby, Sr. Engineering Consultant [email protected]
> Pervasive Software http://pervasive.com work: 512-231-6117
> vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
>
> ---------------------------(end of broadcast)---------------------------
> TIP 3: Have you checked our extensive FAQ?
>
> http://www.postgresql.org/docs/faq
>
--
Bruce Momjian | http://candle.pha.pa.us
[email protected] | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
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Index: doc/src/sgml/maintenance.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/maintenance.sgml,v
retrieving revision 1.51
diff -c -c -r1.51 maintenance.sgml
*** doc/src/sgml/maintenance.sgml 4 Nov 2005 23:14:00 -0000 1.51
--- doc/src/sgml/maintenance.sgml 7 Dec 2005 05:35:08 -0000
***************
*** 141,151 ****
command. The first form, known as <quote>lazy vacuum</quote> or
just <command>VACUUM</command>, marks expired data in tables and
indexes for future reuse; it does <emphasis>not</emphasis> attempt
! to reclaim the space used by this expired data
! immediately. Therefore, the table file is not shortened, and any
! unused space in the file is not returned to the operating
! system. This variant of <command>VACUUM</command> can be run
! concurrently with normal database operations.
</para>
<para>
--- 141,152 ----
command. The first form, known as <quote>lazy vacuum</quote> or
just <command>VACUUM</command>, marks expired data in tables and
indexes for future reuse; it does <emphasis>not</emphasis> attempt
! to reclaim the space used by this expired data unless the space is
! at the end of the table and an exclusive lock can be obtained easily
! on the table. Unused space at the start or middle of the file does
! not result in the file being shortened and space returned to the
! operating system. This variant of <command>VACUUM</command> can be
! run concurrently with normal database operations.
</para>
<para>
Attachments:
[text/plain] /bjm/diff (1.6K, 2-%2Fbjm%2Fdiff)
download | inline:
Index: doc/src/sgml/maintenance.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/maintenance.sgml,v
retrieving revision 1.51
diff -c -c -r1.51 maintenance.sgml
*** doc/src/sgml/maintenance.sgml 4 Nov 2005 23:14:00 -0000 1.51
--- doc/src/sgml/maintenance.sgml 7 Dec 2005 05:35:08 -0000
***************
*** 141,151 ****
command. The first form, known as <quote>lazy vacuum</quote> or
just <command>VACUUM</command>, marks expired data in tables and
indexes for future reuse; it does <emphasis>not</emphasis> attempt
! to reclaim the space used by this expired data
! immediately. Therefore, the table file is not shortened, and any
! unused space in the file is not returned to the operating
! system. This variant of <command>VACUUM</command> can be run
! concurrently with normal database operations.
</para>
<para>
--- 141,152 ----
command. The first form, known as <quote>lazy vacuum</quote> or
just <command>VACUUM</command>, marks expired data in tables and
indexes for future reuse; it does <emphasis>not</emphasis> attempt
! to reclaim the space used by this expired data unless the space is
! at the end of the table and an exclusive lock can be obtained easily
! on the table. Unused space at the start or middle of the file does
! not result in the file being shortened and space returned to the
! operating system. This variant of <command>VACUUM</command> can be
! run concurrently with normal database operations.
</para>
<para>
^ permalink raw reply [nested|flat] 2+ messages in thread
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