Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit4347cc2

Browse files
committed
Allow background writing to be shut down by setting limit values to zero.
This does not disable the bgwriter process: it still has to wake up oftenenough to collect fsync requests from backends in a timely fashion. Butit responds to the recent gripe about not being able to prevent the diskfrom being spun up constantly.
1 parentbdbe9c9 commit4347cc2

File tree

4 files changed

+20
-12
lines changed

4 files changed

+20
-12
lines changed

‎doc/src/sgml/runtime.sgml

Lines changed: 4 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.288 2004/10/15 16:50:29 momjian Exp $
2+
$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.289 2004/10/17 22:01:49 tgl Exp $
33
-->
44

55
<Chapter Id="runtime">
@@ -1305,7 +1305,9 @@ SET ENABLE_SEQSCAN TO OFF;
13051305
<varname>bgwriter_maxpages</varname> reduce the extra I/O load
13061306
caused by the background writer, but leave more work to be done
13071307
at checkpoint time. To reduce load spikes at checkpoints,
1308-
increase the values.
1308+
increase the values. To disable background writing entirely,
1309+
set <varname>bgwriter_percent</varname> and/or
1310+
<varname>bgwriter_maxpages</varname> to zero.
13091311
</para>
13101312
</sect3>
13111313

‎src/backend/storage/buffer/bufmgr.c

Lines changed: 9 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.180 2004/10/16 18:57:23 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.181 2004/10/17 22:01:50 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -671,8 +671,10 @@ UnpinBuffer(BufferDesc *buf, bool fixOwner)
671671
*
672672
* This is called at checkpoint time to write out all dirty shared buffers,
673673
* and by the background writer process to write out some of the dirty blocks.
674-
* percent/maxpages should be zero in the former case, and nonzero limit
675-
* values in the latter.
674+
* percent/maxpages should be -1 in the former case, and limit values (>= 0)
675+
* in the latter.
676+
*
677+
* Returns the number of buffers written.
676678
*/
677679
int
678680
BufferSync(intpercent,intmaxpages)
@@ -682,6 +684,10 @@ BufferSync(int percent, int maxpages)
682684
intnum_buffer_dirty;
683685
inti;
684686

687+
/* If either limit is zero then we are disabled from doing anything... */
688+
if (percent==0||maxpages==0)
689+
return0;
690+
685691
/*
686692
* Get a list of all currently dirty buffers and how many there are.
687693
* We do not flush buffers that get dirtied after we started. They

‎src/backend/utils/misc/guc.c

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
* Written by Peter Eisentraut <peter_e@gmx.net>.
1111
*
1212
* IDENTIFICATION
13-
* $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.244 2004/10/16 19:08:38 tgl Exp $
13+
* $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.245 2004/10/17 22:01:51 tgl Exp $
1414
*
1515
*--------------------------------------------------------------------
1616
*/
@@ -1248,7 +1248,7 @@ static struct config_int ConfigureNamesInt[] =
12481248
NULL
12491249
},
12501250
&BgWriterDelay,
1251-
200,10,5000,NULL,NULL
1251+
200,10,10000,NULL,NULL
12521252
},
12531253

12541254
{
@@ -1257,7 +1257,7 @@ static struct config_int ConfigureNamesInt[] =
12571257
NULL
12581258
},
12591259
&BgWriterPercent,
1260-
1,1,100,NULL,NULL
1260+
1,0,100,NULL,NULL
12611261
},
12621262

12631263
{
@@ -1266,7 +1266,7 @@ static struct config_int ConfigureNamesInt[] =
12661266
NULL
12671267
},
12681268
&BgWriterMaxPages,
1269-
100,1,1000,NULL,NULL
1269+
100,0,1000,NULL,NULL
12701270
},
12711271

12721272
{

‎src/backend/utils/misc/postgresql.conf.sample

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -98,9 +98,9 @@
9898

9999
# - Background writer -
100100

101-
#bgwriter_delay = 200# 10-5000 milliseconds
102-
#bgwriter_percent = 1#1-100% of dirty buffers
103-
#bgwriter_maxpages = 100#1-1000 buffers maxat once
101+
#bgwriter_delay = 200# 10-10000 milliseconds between rounds
102+
#bgwriter_percent = 1#0-100% of dirty buffers in each round
103+
#bgwriter_maxpages = 100#0-1000 buffers maxper round
104104

105105

106106
#---------------------------------------------------------------------------

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp