Index: linux-2.6.21-rc1/mm/slub.c
===================================================================
--- linux-2.6.21-rc1.orig/mm/slub.c	2007-02-25 22:26:15.000000000 -0800
+++ linux-2.6.21-rc1/mm/slub.c	2007-02-26 15:34:11.000000000 -0800
@@ -534,6 +534,12 @@
 	putback_slab(s, page);
 }
 
+static void flush_slab(struct kmem_cache *s, struct page *page, int cpu)
+{
+	slab_lock(page);
+	deactivate_slab(s, page, cpu);
+}
+
 /*
  * Flush cpu slab.
  * Called from IPI handler with interrupts disabled.
@@ -542,10 +548,8 @@
 {
 	struct page *page = s->cpu_slab[cpu];
 
-	if (likely(page)) {
-		slab_lock(page);
-		deactivate_slab(s, page, cpu);
-	}
+	if (likely(page))
+		flush_slab(s, page, cpu);
 }
 
 static void flush_cpu_slab(void *d)
@@ -560,22 +564,18 @@
 /*
  * Called from IPI to check and flush cpu slabs.
  */
-static void check_flush_cpu_slab(void *d)
+static void check_flush_cpu_slab(void *private)
 {
-	struct kmem_cache *s = d;
+	struct kmem_cache *s = private;
 	int cpu = smp_processor_id();
 	struct page *page = s->cpu_slab[cpu];
 
-	if (!page)
-		return;
-
-	if (PageReferenced(page)) {
-		ClearPageReferenced(page);
-		atomic_inc(&s->cpu_slabs);
-	} else {
-		slab_lock(page);
-		deactivate_slab(s, page, cpu);
+	if (page) {
+		if (!TestClearPageReferenced(page))
+			return;
+		flush_slab(s, page, cpu);
 	}
+	atomic_dec(&s->cpu_slabs);
 }
 
 /*
@@ -591,7 +591,7 @@
 	atomic_set(&s->cpu_slabs, num_online_cpus());
 	on_each_cpu(check_flush_cpu_slab, s, 1, 1);
 	if (atomic_read(&s->cpu_slabs))
-		schedule_delayed_work(&s->flush, 2 * HZ);
+		schedule_delayed_work(&s->flush, 30 * HZ);
 	mutex_unlock(&s->flushing);
 }
 
@@ -687,7 +687,7 @@
 #ifdef CONFIG_SMP
 	if (keventd_up() && !atomic_read(&s->cpu_slabs)) {
 		atomic_inc(&s->cpu_slabs);
-		schedule_delayed_work(&s->flush, 2 * HZ);
+		schedule_delayed_work(&s->flush, 30 * HZ);
 	}
 #endif
 	goto redo;
Index: linux-2.6.21-rc1/include/linux/slub_def.h
===================================================================
--- linux-2.6.21-rc1.orig/include/linux/slub_def.h	2007-02-25 22:00:05.000000000 -0800
+++ linux-2.6.21-rc1/include/linux/slub_def.h	2007-02-26 13:49:17.000000000 -0800
@@ -38,10 +38,15 @@
 	struct list_head list;	/* List of slabs */
 #ifdef CONFIG_SMP
 	struct mutex flushing;
-	atomic_t cpu_slabs;	/* if >0 then flusher is scheduled */
+	atomic_t cpu_slabs;	/*
+				 *if >0 then flusher is scheduled. Also used
+				 * to count remaining cpus if flushing
+				 */
 	struct delayed_work flush;
 #endif
+#ifdef CONFIG_NUMA
 	struct kmem_cache_node *node[MAX_NUMNODES];
+#endif
 	struct page *cpu_slab[NR_CPUS];
 };