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

Commite2d394d

Browse files
committed
Use WaitLatch() for condition variables.
Previously, condition_variable.c created a long lived WaitEventSet toavoid extra system calls. WaitLatch() now uses something similarinternally, so there is no point in wasting an extra kernel descriptor.Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>Discussion:https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com
1 parent3347c98 commite2d394d

File tree

1 file changed

+5
-23
lines changed

1 file changed

+5
-23
lines changed

‎src/backend/storage/lmgr/condition_variable.c

Lines changed: 5 additions & 23 deletions
Original file line numberDiff line numberDiff line change
@@ -30,9 +30,6 @@
3030
/* Initially, we are not prepared to sleep on any condition variable. */
3131
staticConditionVariable*cv_sleep_target=NULL;
3232

33-
/* Reusable WaitEventSet. */
34-
staticWaitEventSet*cv_wait_event_set=NULL;
35-
3633
/*
3734
* Initialize a condition variable.
3835
*/
@@ -62,23 +59,6 @@ ConditionVariablePrepareToSleep(ConditionVariable *cv)
6259
{
6360
intpgprocno=MyProc->pgprocno;
6461

65-
/*
66-
* If first time through in this process, create a WaitEventSet, which
67-
* we'll reuse for all condition variable sleeps.
68-
*/
69-
if (cv_wait_event_set==NULL)
70-
{
71-
WaitEventSet*new_event_set;
72-
73-
new_event_set=CreateWaitEventSet(TopMemoryContext,2);
74-
AddWaitEventToSet(new_event_set,WL_LATCH_SET,PGINVALID_SOCKET,
75-
MyLatch,NULL);
76-
AddWaitEventToSet(new_event_set,WL_EXIT_ON_PM_DEATH,PGINVALID_SOCKET,
77-
NULL,NULL);
78-
/* Don't set cv_wait_event_set until we have a correct WES. */
79-
cv_wait_event_set=new_event_set;
80-
}
81-
8262
/*
8363
* If some other sleep is already prepared, cancel it; this is necessary
8464
* because we have just one static variable tracking the prepared sleep,
@@ -135,6 +115,7 @@ ConditionVariableTimedSleep(ConditionVariable *cv, long timeout,
135115
longcur_timeout=-1;
136116
instr_timestart_time;
137117
instr_timecur_time;
118+
intwait_events;
138119

139120
/*
140121
* If the caller didn't prepare to sleep explicitly, then do so now and
@@ -166,19 +147,20 @@ ConditionVariableTimedSleep(ConditionVariable *cv, long timeout,
166147
INSTR_TIME_SET_CURRENT(start_time);
167148
Assert(timeout >=0&&timeout <=INT_MAX);
168149
cur_timeout=timeout;
150+
wait_events=WL_LATCH_SET |WL_TIMEOUT |WL_EXIT_ON_PM_DEATH;
169151
}
152+
else
153+
wait_events=WL_LATCH_SET |WL_EXIT_ON_PM_DEATH;
170154

171155
while (true)
172156
{
173-
WaitEventevent;
174157
booldone= false;
175158

176159
/*
177160
* Wait for latch to be set. (If we're awakened for some other
178161
* reason, the code below will cope anyway.)
179162
*/
180-
(void)WaitEventSetWait(cv_wait_event_set,cur_timeout,&event,1,
181-
wait_event_info);
163+
(void)WaitLatch(MyLatch,wait_events,cur_timeout,wait_event_info);
182164

183165
/* Reset latch before examining the state of the wait list. */
184166
ResetLatch(MyLatch);

0 commit comments

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