Refer to max_wal_senders in a more consistent fashion.

The error message now makes explicit reference to the GUC that must be changed
to fix the problem, using wording suggested by Tom Lane.  Along the way,
rename the GUC from MaxWalSenders to max_wal_senders for consistency and
grep-ability.

3 files changed, 13 insertions, 11 deletions

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 94003c0ce2..dfe2593c99 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.385 2010/03/30 16:23:57 heikki Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.386 2010/04/01 00:43:29 rhaas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -7092,7 +7092,7 @@ CreateCheckPoint(int flags)
 	 * disconnected (e.g because of network problems), but at least it avoids
 	 * an open replication connection from failing because of that.
 	 */
-	if ((_logId || _logSeg) && MaxWalSenders > 0)
+	if ((_logId || _logSeg) && max_wal_senders > 0)
 	{
 		XLogRecPtr	oldest;
 		uint32		log;
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 21058d10ba..e04e5ba65c 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -30,7 +30,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/replication/walsender.c,v 1.13 2010/03/26 12:23:34 heikki Exp $
+ *	  $PostgreSQL: pgsql/src/backend/replication/walsender.c,v 1.14 2010/04/01 00:43:29 rhaas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,7 +64,7 @@ static WalSnd *MyWalSnd = NULL;
 bool		am_walsender = false;		/* Am I a walsender process ? */
 
 /* User-settable parameters for walsender */
-int			MaxWalSenders = 0;	/* the maximum number of concurrent walsenders */
+int			max_wal_senders = 0;	/* the maximum number of concurrent walsenders */
 int			WalSndDelay = 200;	/* max sleep time between some actions */
 
 #define NAPTIME_PER_CYCLE 100000L	/* max sleep time between cycles (100ms) */
@@ -452,7 +452,7 @@ InitWalSnd(void)
 	 * Find a free walsender slot and reserve it. If this fails, we must be
 	 * out of WalSnd structures.
 	 */
-	for (i = 0; i < MaxWalSenders; i++)
+	for (i = 0; i < max_wal_senders; i++)
 	{
 		volatile WalSnd *walsnd = &WalSndCtl->walsnds[i];
 
@@ -476,7 +476,9 @@ InitWalSnd(void)
 	if (MyWalSnd == NULL)
 		ereport(FATAL,
 				(errcode(ERRCODE_TOO_MANY_CONNECTIONS),
-				 errmsg("sorry, too many standbys already")));
+				 errmsg("number of requested standby connections "
+					"exceeds max_wal_senders (currently %d)",
+					max_wal_senders)));
 
 	/* Arrange to clean up at walsender exit */
 	on_shmem_exit(WalSndKill, 0);
@@ -766,7 +768,7 @@ WalSndShmemSize(void)
 	Size		size = 0;
 
 	size = offsetof(WalSndCtlData, walsnds);
-	size = add_size(size, mul_size(MaxWalSenders, sizeof(WalSnd)));
+	size = add_size(size, mul_size(max_wal_senders, sizeof(WalSnd)));
 
 	return size;
 }
@@ -791,7 +793,7 @@ WalSndShmemInit(void)
 	/* Initialize the data structures */
 	MemSet(WalSndCtl, 0, WalSndShmemSize());
 
-	for (i = 0; i < MaxWalSenders; i++)
+	for (i = 0; i < max_wal_senders; i++)
 	{
 		WalSnd	   *walsnd = &WalSndCtl->walsnds[i];
 
@@ -810,7 +812,7 @@ GetOldestWALSendPointer(void)
 	int			i;
 	bool		found = false;
 
-	for (i = 0; i < MaxWalSenders; i++)
+	for (i = 0; i < max_wal_senders; i++)
 	{
 		/* use volatile pointer to prevent code rearrangement */
 		volatile WalSnd *walsnd = &WalSndCtl->walsnds[i];
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ea43b4171b..5f8cc49489 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.545 2010/03/25 14:44:33 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.546 2010/04/01 00:43:29 rhaas Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -1705,7 +1705,7 @@ static struct config_int ConfigureNamesInt[] =
 			gettext_noop("Sets the maximum number of simultaneously running WAL sender processes."),
 			NULL
 		},
-		&MaxWalSenders,
+		&max_wal_senders,
 		0, 0, INT_MAX / 4, NULL, NULL
 	},