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Create a standard function pg_sleep() to sleep for a specified amount of time.

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Replace the former ad-hoc implementation used in the regression tests.
Joachim Wieland
This commit is contained in:
Tom Lane
2006-01-11 20:12:43 +00:00
parent fb627b76cc
commit 782eefc580
10 changed files with 112 additions and 35 deletions
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51
src/backend/utils/adt/misc.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/misc.c,v 1.49 2005/10/15 02:49:29 momjian Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/misc.c,v 1.50 2006/01/11 20:12:39 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -17,6 +17,7 @@
#include <sys/file.h>
#include <signal.h>
#include <dirent.h>
#include <math.h>
#include "catalog/pg_tablespace.h"
#include "catalog/pg_type.h"
@ -259,3 +260,51 @@ pg_tablespace_databases(PG_FUNCTION_ARGS)
FreeDir(fctx->dirdesc);
SRF_RETURN_DONE(funcctx);
}
/*
* pg_sleep - delay for N seconds
*/
Datum
pg_sleep(PG_FUNCTION_ARGS)
{
float8 secs = PG_GETARG_FLOAT8(0);
float8 endtime;
/*
* We break the requested sleep into segments of no more than 1 second,
* to put an upper bound on how long it will take us to respond to a
* cancel or die interrupt. (Note that pg_usleep is interruptible by
* signals on some platforms but not others.) Also, this method avoids
* exposing pg_usleep's upper bound on allowed delays.
*
* By computing the intended stop time initially, we avoid accumulation
* of extra delay across multiple sleeps. This also ensures we won't
* delay less than the specified time if pg_usleep is interrupted
* by other signals such as SIGHUP.
*/
#ifdef HAVE_INT64_TIMESTAMP
#define GetNowFloat() ((float8) GetCurrentTimestamp() / 1000000.0)
#else
#define GetNowFloat() GetCurrentTimestamp()
#endif
endtime = GetNowFloat() + secs;
for (;;)
{
float8 delay;
CHECK_FOR_INTERRUPTS();
delay = endtime - GetNowFloat();
if (delay >= 1.0)
pg_usleep(1000000L);
else if (delay > 0.0)
pg_usleep((long) ceil(delay * 1000000.0));
else
break;
}
PG_RETURN_VOID();
}