From 686956375a84f4ac9f214e402e9922b49813784a Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Thu, 22 Mar 2007 19:53:31 +0000
Subject: [PATCH] Allow the pgstat process to restart immediately after a
 receiving SIGQUIT signal, rather than waiting for PGSTAT_RESTART_INTERVAL.

---
 src/backend/postmaster/pgstat.c     |  6 +++++-
 src/backend/postmaster/postmaster.c | 15 ++++++++++++++-
 src/include/pgstat.h                |  4 ++--
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 378e165707..26e6ff4ca0 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -13,7 +13,7 @@
  *
  *	Copyright (c) 2001-2007, PostgreSQL Global Development Group
  *
- *	$PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.149 2007/03/16 17:57:36 mha Exp $
+ *	$PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.150 2007/03/22 19:53:30 momjian Exp $
  * ----------
  */
 #include "postgres.h"
@@ -572,6 +572,10 @@ pgstat_start(void)
 	return 0;
 }
 
+void allow_immediate_pgstat_restart(void)
+{
+		last_pgstat_start_time = 0;
+}
 
 /* ------------------------------------------------------------
  * Public functions used by backends follow
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 261b957043..385185eddb 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -37,7 +37,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.526 2007/03/07 13:35:02 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.527 2007/03/22 19:53:30 momjian Exp $
  *
  * NOTES
  *
@@ -1896,7 +1896,10 @@ pmdie(SIGNAL_ARGS)
 				signal_child(PgArchPID, SIGQUIT);
 			/* Tell pgstat to shut down too; nothing left for it to do */
 			if (PgStatPID != 0)
+			{
 				signal_child(PgStatPID, SIGQUIT);
+				allow_immediate_pgstat_restart();
+			}
 			/* Tell autovac launcher to shut down too */
 			if (AutoVacPID != 0)
 				signal_child(AutoVacPID, SIGTERM);
@@ -1952,7 +1955,10 @@ pmdie(SIGNAL_ARGS)
 				signal_child(PgArchPID, SIGQUIT);
 			/* Tell pgstat to shut down too; nothing left for it to do */
 			if (PgStatPID != 0)
+			{
 				signal_child(PgStatPID, SIGQUIT);
+				allow_immediate_pgstat_restart();
+			}
 			/* Tell autovac launcher to shut down too */
 			if (AutoVacPID != 0)
 				signal_child(AutoVacPID, SIGTERM);
@@ -1977,7 +1983,10 @@ pmdie(SIGNAL_ARGS)
 			if (PgArchPID != 0)
 				signal_child(PgArchPID, SIGQUIT);
 			if (PgStatPID != 0)
+			{
 				signal_child(PgStatPID, SIGQUIT);
+				allow_immediate_pgstat_restart();
+			}
 			if (DLGetHead(BackendList))
 				SignalChildren(SIGQUIT);
 			ExitPostmaster(0);
@@ -2241,7 +2250,10 @@ reaper(SIGNAL_ARGS)
 			signal_child(PgArchPID, SIGQUIT);
 		/* Tell pgstat to shut down too; nothing left for it to do */
 		if (PgStatPID != 0)
+		{
 			signal_child(PgStatPID, SIGQUIT);
+			allow_immediate_pgstat_restart();
+		}
 		/* Tell autovac launcher to shut down too */
 		if (AutoVacPID != 0)
 			signal_child(AutoVacPID, SIGTERM);
@@ -2404,6 +2416,7 @@ HandleChildCrash(int pid, int exitstatus, const char *procname)
 								 "SIGQUIT",
 								 (int) PgStatPID)));
 		signal_child(PgStatPID, SIGQUIT);
+		allow_immediate_pgstat_restart();
 	}
 
 	/* We do NOT restart the syslogger */
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ce0333a787..8e08db4c17 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -5,7 +5,7 @@
  *
  *	Copyright (c) 2001-2007, PostgreSQL Global Development Group
  *
- *	$PostgreSQL: pgsql/src/include/pgstat.h,v 1.55 2007/03/16 17:57:36 mha Exp $
+ *	$PostgreSQL: pgsql/src/include/pgstat.h,v 1.56 2007/03/22 19:53:31 momjian Exp $
  * ----------
  */
 #ifndef PGSTAT_H
@@ -369,7 +369,7 @@ extern void CreateSharedBackendStatus(void);
 extern void pgstat_init(void);
 extern int	pgstat_start(void);
 extern void pgstat_reset_all(void);
-
+extern void allow_immediate_pgstat_restart(void);
 #ifdef EXEC_BACKEND
 extern void PgstatCollectorMain(int argc, char *argv[]);
 #endif