In a bootstrap process or standalone backend, set MaxBackends = 1

tglsfdc · tglsfdc · commit 565c97bea549 · 2002-10-03T19:19:09.000Z
to avoid unnecessary consumption of semaphores.
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.116 2002/09/04 20:31:31 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.117 2002/10/03 19:19:09 tgl Exp $
  *
  *
  *-------------------------------------------------------------------------
@@ -172,11 +172,14 @@ InitCommunication(void)
 	if (!IsUnderPostmaster)		/* postmaster already did this */
 	{
 		/*
-		 * we're running a postgres backend by itself with no front end or
-		 * postmaster.	Create private "shmem" and semaphores.	Setting
-		 * MaxBackends = 16 is arbitrary.
+		 * We're running a postgres bootstrap process or a standalone backend.
+		 * Create private "shmem" and semaphores.  Force MaxBackends to 1 so
+		 * that we don't allocate more resources than necessary.
 		 */
-		CreateSharedMemoryAndSemaphores(true, 16, 0);
+		SetConfigOption("max_connections", "1",
+						PGC_POSTMASTER, PGC_S_OVERRIDE);
+
+		CreateSharedMemoryAndSemaphores(true, MaxBackends, 0);
 	}
 }
 

Original file line number	Diff line number	Diff line change
`@@ -8,7 +8,7 @@`
`8`	`8`	`*`
`9`	`9`	`*`
`10`	`10`	`* IDENTIFICATION`
`11`		`- * $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.116 2002/09/04 20:31:31 momjian Exp $`
	`11`	`+ * $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.117 2002/10/03 19:19:09 tgl Exp $`
`12`	`12`	`*`
`13`	`13`	`*`
`14`	`14`	`*-------------------------------------------------------------------------`
`@@ -172,11 +172,14 @@ InitCommunication(void)`
`172`	`172`	`if (!IsUnderPostmaster) /* postmaster already did this */`
`173`	`173`	`{`
`174`	`174`	`/*`
`175`		`- * we're running a postgres backend by itself with no front end or`
`176`		`- * postmaster. Create private "shmem" and semaphores. Setting`
`177`		`- * MaxBackends = 16 is arbitrary.`
	`175`	`+ * We're running a postgres bootstrap process or a standalone backend.`
	`176`	`+ * Create private "shmem" and semaphores. Force MaxBackends to 1 so`
	`177`	`+ * that we don't allocate more resources than necessary.`
`178`	`178`	`*/`
`179`		`- CreateSharedMemoryAndSemaphores(true, 16, 0);`
	`179`	`+ SetConfigOption("max_connections", "1",`
	`180`	`+ PGC_POSTMASTER, PGC_S_OVERRIDE);`
	`181`	`+`
	`182`	`+ CreateSharedMemoryAndSemaphores(true, MaxBackends, 0);`
`180`	`183`	`}`
`181`	`184`	`}`
`182`	`185`