diff -urN oldtree/include/linux/mmzone.h newtree/include/linux/mmzone.h
--- oldtree/include/linux/mmzone.h	2006-09-26 15:14:49.000000000 -0400
+++ newtree/include/linux/mmzone.h	2006-09-26 15:16:46.000000000 -0400
@@ -400,7 +400,7 @@
 			unsigned long *free);
 unsigned long nr_free_inactive_pages_node(int nid);
 void build_all_zonelists(void);
-void wakeup_kswapd(struct zone *zone, int order);
+void wakeup_kswapd(struct zone *zone, int order, struct task_struct *p);
 int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
 		int classzone_idx, int alloc_flags);
 
diff -urN oldtree/mm/page_alloc.c newtree/mm/page_alloc.c
--- oldtree/mm/page_alloc.c	2006-09-26 15:14:49.000000000 -0400
+++ newtree/mm/page_alloc.c	2006-09-26 15:16:46.000000000 -0400
@@ -1069,7 +1069,7 @@
 		goto got_pg;
 
 	do {
-		wakeup_kswapd(*z, order);
+		wakeup_kswapd(*z, order, p);
 	} while (*(++z));
 
 	/*
diff -urN oldtree/mm/vmscan.c newtree/mm/vmscan.c
--- oldtree/mm/vmscan.c	2006-09-26 15:14:49.000000000 -0400
+++ newtree/mm/vmscan.c	2006-09-26 15:16:46.000000000 -0400
@@ -945,6 +945,39 @@
 }
 
 /*
+ * Helper functions to adjust nice level of kswapd, based on the priority of
+ * the task (p) that called it. If it is already higher priority we do not
+ * demote its nice level since it is still working on behalf of a higher
+ * priority task. With kernel threads we leave it at nice 0.
+ *
+ * We don't ever run kswapd real time, so if a real time task calls kswapd we
+ * set it to highest SCHED_NORMAL priority.
+ */
+static int effective_sc_prio(struct task_struct *p)
+{
+	if (likely(p->mm)) {
+		if (rt_task(p))
+			return -20;
+		return task_nice(p);
+	}
+	return 0;
+}
+
+static void set_kswapd_nice(struct task_struct *kswapd, struct task_struct *p,
+			    int active)
+{
+	long nice = effective_sc_prio(p);
+
+	if (task_nice(kswapd) > nice || !active)
+		set_user_nice(kswapd, nice);
+}
+
+static int sc_priority(struct task_struct *p)
+{
+	return (DEF_PRIORITY + (DEF_PRIORITY * effective_sc_prio(p) / 40));
+}
+
+/*
  * This is the direct reclaim path, for page-allocating processes.  We only
  * try to reclaim pages from zones which will satisfy the caller's allocation
  * request.
@@ -1315,6 +1348,7 @@
 			 */
 			order = new_order;
 		} else {
+			set_user_nice(tsk, 0);
 			schedule();
 			order = pgdat->kswapd_max_order;
 		}
@@ -1328,9 +1362,10 @@
 /*
  * A zone is low on free memory, so wake its kswapd task to service it.
  */
-void wakeup_kswapd(struct zone *zone, int order)
+void wakeup_kswapd(struct zone *zone, int order, struct task_struct *p)
 {
 	pg_data_t *pgdat;
+	int active;
 
 	if (!populated_zone(zone))
 		return;
@@ -1342,7 +1377,9 @@
 		pgdat->kswapd_max_order = order;
 	if (!cpuset_zone_allowed(zone, __GFP_HARDWALL))
 		return;
-	if (!waitqueue_active(&pgdat->kswapd_wait))
+	active = waitqueue_active(&pgdat->kswapd_wait);
+	set_kswapd_nice(pgdat->kswapd, p, active);
+	if (!active)
 		return;
 	wake_up_interruptible(&pgdat->kswapd_wait);
 }