[pgpool-general-jp: 251] Re: pgpoolの縮退運転について

[Yoshiyuki Asaba]

浅羽です。

From: "吉元良史" <y-yoshi ＠ wit.co.jp>
Subject: [pgpool-general-jp: 250] pgpoolの縮退運転について
Date: Thu, 13 Sep 2007 15:25:38 +0900

> テストにて手動でpc2のPostgreSQLを停止した後、最初にSELECT文を発行した時にフリーズしてしまいます。

手元でも再現させることができました。
添付のパッチで症状は改善されるでしょうか？

configure のあるディレクトリにコピーして

  % patch < diff
  % make install

してみてください。よろしくお願いします。
--
Yoshiyuki Asaba
y-asaba ＠ sraoss.co.jp
-------------- next part --------------
Index: child.c
===================================================================
RCS file: /cvsroot/pgpool/pgpool-II/child.c,v
retrieving revision 1.5.2.4
diff -u -r1.5.2.4 child.c
--- child.c	10 Sep 2007 13:34:38 -0000	1.5.2.4
+++ child.c	14 Sep 2007 06:49:48 -0000
@@ -66,7 +66,6 @@
 static int send_params(POOL_CONNECTION *frontend, POOL_CONNECTION_POOL *backend);
 static void send_frontend_exits(void);
 static int s_do_auth(POOL_CONNECTION_POOL_SLOT *cp, char *password);
-static int select_load_balancing_node(void);
 
 /*
  * non 0 means SIGTERM(smart shutdown) or SIGINT(fast shutdown) has arrived
@@ -1646,7 +1645,7 @@
 /*
  * Select load balancing node
  */
-static int select_load_balancing_node(void)
+int select_load_balancing_node(void)
 {
 	double total_weight,r;
 	int i;
Index: pool.h
===================================================================
RCS file: /cvsroot/pgpool/pgpool-II/pool.h,v
retrieving revision 1.5.2.5
diff -u -r1.5.2.5 pool.h
--- pool.h	26 Jul 2007 09:03:04 -0000	1.5.2.5
+++ pool.h	14 Sep 2007 06:49:48 -0000
@@ -383,6 +383,7 @@
 extern int pool_get_config(char *confpath);
 extern void do_child(int unix_fd, int inet_fd);
 extern void pcp_do_child(int unix_fd, int inet_fd, char *pcp_conf_file);
+extern int select_load_balancing_node(void);
 extern int pool_init_cp(void);
 extern POOL_STATUS pool_process_query(POOL_CONNECTION *frontend,
 									  POOL_CONNECTION_POOL *backend,
Index: pool_process_query.c
===================================================================
RCS file: /cvsroot/pgpool/pgpool-II/pool_process_query.c,v
retrieving revision 1.23.2.14
diff -u -r1.23.2.14 pool_process_query.c
--- pool_process_query.c	29 Aug 2007 05:53:41 -0000	1.23.2.14
+++ pool_process_query.c	14 Sep 2007 06:49:51 -0000
@@ -283,6 +283,12 @@
 
 			num_fds = 0;
 
+			if (!VALID_BACKEND(backend->info->load_balancing_node))
+			{
+				/* select load balancing node */
+				backend->info->load_balancing_node = select_load_balancing_node();
+			}
+
 			for (i=0;i<NUM_BACKENDS;i++)
 			{
 				if (VALID_BACKEND(i))
@@ -322,6 +328,8 @@
 					if (detect_postmaster_down_error(CONNECTION(backend, i), MAJOR(backend)))
 					{
 						was_error = 1;
+						if (!VALID_BACKEND(i))
+							break;
 						notice_backend_error(i);
 						sleep(5);
 						break;
@@ -346,9 +354,9 @@
 					status = ProcessFrontendResponse(frontend, backend);
 					if (status != POOL_CONTINUE)
 						return status;
-
-					continue;
 				}
+				if (kind == 0)
+					continue;
 			}
 			
 			if (FD_ISSET(MASTER(backend)->fd, &exceptmask))