diff --git a/ChangeLog b/ChangeLog
index 500a7435c..927332d6f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2009-09-07 Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSRunLoop.m:
+	* Source/GSRunLoopCtxt.h:
+	Add some logging to help debug problems where code is adding too
+	many events into a run loop.
+
 2009-09-06 Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/NSLock.m: Fix the ([-tryLock]) and [(-lockBeforeDate:])
diff --git a/Source/GSRunLoopCtxt.h b/Source/GSRunLoopCtxt.h
index 76ffe362f..091c9859e 100644
--- a/Source/GSRunLoopCtxt.h
+++ b/Source/GSRunLoopCtxt.h
@@ -62,8 +62,11 @@ typedef struct{
   void		*extra;		/** Copy of the RunLoop ivar.		*/
   NSString	*mode;		/** The mode for this context.		*/
   GSIArray	performers;	/** The actions to perform regularly.	*/
+  unsigned	maxPerformers;
   GSIArray	timers;		/** The timers set for the runloop mode */
+  unsigned	maxTimers;
   GSIArray	watchers;	/** The inputs set for the runloop mode */
+  unsigned	maxWatchers;
   NSTimer	*housekeeper;	/** Housekeeping timer for loop.	*/
 @private
 #if	defined(__MINGW32__)
diff --git a/Source/NSRunLoop.m b/Source/NSRunLoop.m
index f7255b8e1..5e461e692 100644
--- a/Source/NSRunLoop.m
+++ b/Source/NSRunLoop.m
@@ -405,6 +405,7 @@ static inline BOOL timerInvalidated(NSTimer *t)
 {
   GSRunLoopCtxt	*context;
   GSIArray	watchers;
+  unsigned	i;
 
   context = NSMapGet(_contextMap, mode);
   if (context == nil)
@@ -415,6 +416,13 @@ static inline BOOL timerInvalidated(NSTimer *t)
     }
   watchers = context->watchers;
   GSIArrayAddItem(watchers, (GSIArrayItem)((id)item));
+  i = GSIArrayCount(watchers);
+  if (i % 1000 == 0 && i > context->maxWatchers)
+    {
+      context->maxWatchers = i;
+      NSLog(@"WARNING ... there are %u watchers scheduled in mode %@ of %@",
+	i, mode, self);
+    }
 }
 
 - (void) _checkPerformers: (GSRunLoopCtxt*)context
@@ -840,6 +848,13 @@ static inline BOOL timerInvalidated(NSTimer *t)
    * all each time -limitDateForMode: is called.
    */
   GSIArrayAddItem(timers, (GSIArrayItem)((id)timer));
+  i = GSIArrayCount(timers);
+  if (i % 1000 == 0 && i > context->maxTimers)
+    {
+      context->maxTimers = i;
+      NSLog(@"WARNING ... there are %u timers scheduled in mode %@ of %@",
+	i, mode, self);
+    }
 }
 
 
@@ -1484,6 +1499,13 @@ static inline BOOL timerInvalidated(NSTimer *t)
 	    {
 	      GSIArrayInsertItem(performers, (GSIArrayItem)((id)item), i);
 	    }
+	  i = GSIArrayCount(performers);
+	  if (i % 1000 == 0 && i > context->maxPerformers)
+	    {
+	      context->maxPerformers = i;
+	      NSLog(@"WARNING ... there are %u performers scheduled"
+		@" in mode %@ of %@", i, mode, self);
+	    }
 	}
       RELEASE(item);
     }