[PATCHES] pg_postmaster_reload_time() patch
I've done a quick write up for reload time reporting from the
administration TODO. I was a little paranoid with the locking, but
didn't want problems to occur with signals on the postmaster and the
read side.
-George
*** ./doc/src/sgml/func.sgml.orig 2008-04-29 23:47:39.378726574 -0400
--- ./doc/src/sgml/func.sgml 2008-04-29 23:51:12.346237119 -0400
***
*** 10892,10897
--- 10892,10903
/row
row
+entryliteralfunctionpg_postmaster_reload_time/function()/literal/entry
+entrytypetimestamp with time zone/type/entry
+entryserver last reload time/entry
+ /row
+
+ row
entryliteralfunctionsession_user/function/literal/entry
entrytypename/type/entry
entrysession user name/entry
***
*** 11037,11042
--- 11043,11062
/para
indexterm
+ primarypg_postmaster_reload_time/primary
+/indexterm
+
+para
+ functionpg_postmaster_reload_time/function returns the
+ typetimestamp with time zone/type when the
+ server was last reloaded.
+/para
+
+indexterm
+ primaryversion/primary
+/indexterm
+
+indexterm
primaryversion/primary
/indexterm
*** ./src/backend/postmaster/postmaster.c.orig 2008-04-29 23:48:07.374455697 -0400
--- ./src/backend/postmaster/postmaster.c 2008-04-29 23:51:12.346237119 -0400
***
*** 112,117
--- 112,118
#include storage/pg_shmem.h
#include storage/pmsignal.h
#include storage/proc.h
+ #include storage/spin.h
#include tcop/tcopprot.h
#include utils/builtins.h
#include utils/datetime.h
***
*** 390,395
--- 391,398
InheritableSocket pgStatSock;
pid_t PostmasterPid;
TimestampTz PgStartTime;
+ TimestampTz PgReloadTime;
+ slock_t PgReloadTimeLock;
bool redirection_done;
#ifdef WIN32
HANDLE PostmasterHandle;
***
*** 1008,1013
--- 1011,1018
* Remember postmaster startup time
*/
PgStartTime = GetCurrentTimestamp();
+ PgReloadTime = PgStartTime;
+ SpinLockInit(PgReloadTimeLock);
/* PostmasterRandom wants its own copy */
gettimeofday(random_start_time, NULL);
***
*** 1931,1936
--- 1936,1948
/* Update the starting-point file for future children */
write_nondefault_variables(PGC_SIGHUP);
#endif
+
+ /*
+ * Remember postmaster reload time
+ */
+ SpinLockAcquire(PgReloadTimeLock);
+ PgReloadTime = GetCurrentTimestamp();
+ SpinLockRelease(PgReloadTimeLock);
}
PG_SETMASK(UnBlockSig);
***
*** 4263,4268
--- 4275,4282
param-PostmasterPid = PostmasterPid;
param-PgStartTime = PgStartTime;
+ param-PgReloadTime = PgReloadTime;
+ param-PgReloadTimeLock = PgReloadTimeLock;
param-redirection_done = redirection_done;
*** ./src/backend/tcop/postgres.c.orig 2008-04-29 23:48:58.866600196 -0400
--- ./src/backend/tcop/postgres.c 2008-04-29 23:51:12.346237119 -0400
***
*** 58,63
--- 58,64
#include storage/ipc.h
#include storage/proc.h
#include storage/sinval.h
+ #include storage/spin.h
#include tcop/fastpath.h
#include tcop/pquery.h
#include tcop/tcopprot.h
***
*** 3373,3380
/*
* Remember stand-alone backend startup time
*/
! if (!IsUnderPostmaster)
PgStartTime = GetCurrentTimestamp();
/*
* POSTGRES main processing loop begins here
--- 3374,3384
/*
* Remember stand-alone backend startup time
*/
! if (!IsUnderPostmaster) {
PgStartTime = GetCurrentTimestamp();
+ PgReloadTime = PgStartTime;
+ SpinLockInit(PgReloadTimeLock);
+ }
/*
* POSTGRES main processing loop begins here
***
*** 3550,3555
--- 3554,3566
{
got_SIGHUP = false;
ProcessConfigFile(PGC_SIGHUP);
+
+ /*
+ * Remember postmaster reload time
+ */
+ SpinLockAcquire(PgReloadTimeLock);
+ PgReloadTime = GetCurrentTimestamp();
+ SpinLockRelease(PgReloadTimeLock);
}
/*
*** ./src/backend/utils/adt/timestamp.c.orig 2008-04-29 23:49:46.359354923 -0400
--- ./src/backend/utils/adt/timestamp.c 2008-04-29 23:51:12.346237119 -0400
***
*** 27,32
--- 27,33
#include libpq/pqformat.h
#include miscadmin.h
#include parser/scansup.h
+ #include storage/spin.h
#include utils/array.h
#include utils/builtins.h
#include utils/datetime.h
***
*** 42,47
--- 43,50
/* Set at postmaster start */
TimestampTz PgStartTime;
+ TimestampTz PgReloadTime;
+ slock_t PgReloadTimeLock;
static TimeOffset time2t(const int hour, const int min, const int sec, const fsec_t fsec);
***
*** 1162,1167
--- 1165,1180
PG_RETURN_TIMESTAMPTZ(PgStartTime);
}
+ Datum
+ pgsql_postmaster_reload_time(PG_FUNCTION_ARGS)
+ {
+ TimestampTz timestamp;
+ SpinLockAcquire(PgReloadTimeLock);
+ timestamp = PgReloadTime;
+ SpinLockRelease(PgReloadTimeLock);
+
Re: [PATCHES] pg_postmaster_reload_time() patch
On Wed, Apr 30, 2008 at 8:16 AM, Alvaro Herrera
[EMAIL PROTECTED] wrote:
George Gensure escribió:
I've done a quick write up for reload time reporting from the
administration TODO. I was a little paranoid with the locking, but
didn't want problems to occur with signals on the postmaster and the
read side.
I'd say too much -- postmaster runs with signals blocked all the time
(except during select()) so this is not necessary there.
Regarding the locking on backends, I admit I am not sure if this is
really a problem enough that you need a spinlock for it. Anyway we tend
not to use spinlocks too much -- probably an LWLock would be more
apropos, if a lock is really needed. (A bigger question is whether the
reload time should be local for each backend, or exposed globally
through MyProc. I don't think it's interesting enough to warrant that,
but perhaps others think differently.)
Lastly, I didn't read the patch close enough to tell if it would work on
both the EXEC_BACKEND case and the regular one.
--
Alvaro Herrerahttp://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.
I've reworked the patch in response to comments.
The new function name is pg_conf_load_time()
I'm now using LWLocks only on the backend in order to protect the
PgReloadTime from mid copy reads. This may prove to be unnecessary,
since the code to handle HUPs seems to be executed synchronously on
the backend, but I'll let someone else tell me its safe before
removing it.
-George
*** ./doc/src/sgml/func.sgml.orig 2008-04-29 23:47:39.378726574 -0400
--- ./doc/src/sgml/func.sgml 2008-04-30 11:31:38.434893712 -0400
***
*** 10892,10897
--- 10892,10903
/row
row
+entryliteralfunctionpg_conf_load_time/function()/literal/entry
+entrytypetimestamp with time zone/type/entry
+entryconfig load time/entry
+ /row
+
+ row
entryliteralfunctionsession_user/function/literal/entry
entrytypename/type/entry
entrysession user name/entry
***
*** 11037,11042
--- 11043,11062
/para
indexterm
+ primarypg_conf_load_time/primary
+/indexterm
+
+para
+ functionpg_conf_load_time/function returns the
+ typetimestamp with time zone/type when the
+ config was last loaded for this session.
+/para
+
+indexterm
+ primaryversion/primary
+/indexterm
+
+indexterm
primaryversion/primary
/indexterm
*** ./src/backend/postmaster/postmaster.c.orig 2008-04-29 23:48:07.374455697 -0400
--- ./src/backend/postmaster/postmaster.c 2008-04-30 12:02:05.156215936 -0400
***
*** 390,395
--- 390,396
InheritableSocket pgStatSock;
pid_t PostmasterPid;
TimestampTz PgStartTime;
+ TimestampTz PgReloadTime;
bool redirection_done;
#ifdef WIN32
HANDLE PostmasterHandle;
***
*** 1008,1013
--- 1009,1015
* Remember postmaster startup time
*/
PgStartTime = GetCurrentTimestamp();
+ PgReloadTime = PgStartTime;
/* PostmasterRandom wants its own copy */
gettimeofday(random_start_time, NULL);
***
*** 1931,1936
--- 1933,1943
/* Update the starting-point file for future children */
write_nondefault_variables(PGC_SIGHUP);
#endif
+
+ /*
+ * Remember config load time
+ */
+ PgReloadTime = GetCurrentTimestamp();
}
PG_SETMASK(UnBlockSig);
***
*** 4263,4268
--- 4270,4276
param-PostmasterPid = PostmasterPid;
param-PgStartTime = PgStartTime;
+ param-PgReloadTime = PgReloadTime;
param-redirection_done = redirection_done;
*** ./src/backend/tcop/postgres.c.orig 2008-04-29 23:48:58.866600196 -0400
--- ./src/backend/tcop/postgres.c 2008-04-30 12:21:40.476913468 -0400
***
*** 58,63
--- 58,64
#include storage/ipc.h
#include storage/proc.h
#include storage/sinval.h
+ #include storage/spin.h
#include tcop/fastpath.h
#include tcop/pquery.h
#include tcop/tcopprot.h
***
*** 3375,3380
--- 3376,3382
*/
if (!IsUnderPostmaster)
PgStartTime = GetCurrentTimestamp();
+ PgReloadTime = PgStartTime;
/*
* POSTGRES main processing loop begins here
***
*** 3550,3555
--- 3552,3564
{
got_SIGHUP = false;
ProcessConfigFile(PGC_SIGHUP);
+
+ /*
+ * Remember config load time
+ */
+ LWLockAcquire(ReloadTimeLock, LW_EXCLUSIVE);
+ PgReloadTime = GetCurrentTimestamp();
+ LWLockRelease(ReloadTimeLock);
}
/*
*** ./src/backend/utils/adt/timestamp.c.orig 2008-04-29 23:49:46.359354923 -0400
--- ./src/backend/utils/adt/timestamp.c 2008-04-30 12:23:52.456779063 -0400
***
*** 42,47
--- 42,49
/* Set at postmaster start */
TimestampTz PgStartTime;
+ /* Set at configuration reload */
+ TimestampTz PgReloadTime;
static
Re: [PATCHES] pg_postmaster_reload_time() patch
On Wed, Apr 30, 2008 at 12:58 PM, George Gensure [EMAIL PROTECTED] wrote: On Wed, Apr 30, 2008 at 8:16 AM, Alvaro Herrera [EMAIL PROTECTED] wrote: George Gensure escribió: I've done a quick write up for reload time reporting from the administration TODO. I was a little paranoid with the locking, but didn't want problems to occur with signals on the postmaster and the read side. I'd say too much -- postmaster runs with signals blocked all the time (except during select()) so this is not necessary there. Regarding the locking on backends, I admit I am not sure if this is really a problem enough that you need a spinlock for it. Anyway we tend not to use spinlocks too much -- probably an LWLock would be more apropos, if a lock is really needed. (A bigger question is whether the reload time should be local for each backend, or exposed globally through MyProc. I don't think it's interesting enough to warrant that, but perhaps others think differently.) Lastly, I didn't read the patch close enough to tell if it would work on both the EXEC_BACKEND case and the regular one. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. I've reworked the patch in response to comments. The new function name is pg_conf_load_time() I'm now using LWLocks only on the backend in order to protect the PgReloadTime from mid copy reads. This may prove to be unnecessary, since the code to handle HUPs seems to be executed synchronously on the backend, but I'll let someone else tell me its safe before removing it. -George So if nobody's got any further objections, could this patch be applied? -George -- Sent via pgsql-patches mailing list (pgsql-patches@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches
Re: [PATCHES] pg_postmaster_reload_time() patch
On Fri, May 2, 2008 at 10:31 AM, Alvaro Herrera [EMAIL PROTECTED] wrote: George Gensure escribió: So if nobody's got any further objections, could this patch be applied? It's in the queue: http://wiki.postgresql.org/wiki/CommitFest:May -- Alvaro Herrerahttp://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. Thanks! -George -- Sent via pgsql-patches mailing list (pgsql-patches@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches
