diff -Naurp --exclude-from=/home/con/kernel/dontdiff linux-2.6.7-rc3-base/include/linux/swap.h linux-2.6.7-rc3-as2/include/linux/swap.h
--- linux-2.6.7-rc3-base/include/linux/swap.h	2004-06-10 23:29:04.000000000 +1000
+++ linux-2.6.7-rc3-as2/include/linux/swap.h	2004-06-14 01:39:51.503649893 +1000
@@ -175,6 +175,7 @@ extern void swap_setup(void);
 extern int try_to_free_pages(struct zone **, unsigned int, unsigned int);
 extern int shrink_all_memory(int);
 extern int vm_swappiness;
+extern int vm_autoregulate;
 
 #ifdef CONFIG_MMU
 /* linux/mm/shmem.c */
diff -Naurp --exclude-from=/home/con/kernel/dontdiff linux-2.6.7-rc3-base/include/linux/sysctl.h linux-2.6.7-rc3-as2/include/linux/sysctl.h
--- linux-2.6.7-rc3-base/include/linux/sysctl.h	2004-06-10 23:29:04.000000000 +1000
+++ linux-2.6.7-rc3-as2/include/linux/sysctl.h	2004-06-14 01:39:22.565122113 +1000
@@ -164,6 +164,7 @@ enum
 	VM_LAPTOP_MODE=23,	/* vm laptop mode */
 	VM_BLOCK_DUMP=24,	/* block dump mode */
 	VM_HUGETLB_GROUP=25,	/* permitted hugetlb group */
+	VM_AUTOREGULATE=26,	/* swappiness and inactivation autoregulated */
 };
 
 
diff -Naurp --exclude-from=/home/con/kernel/dontdiff linux-2.6.7-rc3-base/kernel/sysctl.c linux-2.6.7-rc3-as2/kernel/sysctl.c
--- linux-2.6.7-rc3-base/kernel/sysctl.c	2004-06-10 23:29:04.000000000 +1000
+++ linux-2.6.7-rc3-as2/kernel/sysctl.c	2004-06-14 01:40:55.567749225 +1000
@@ -727,6 +727,14 @@ static ctl_table vm_table[] = {
 		.extra1		= &zero,
 		.extra2		= &one_hundred,
 	},
+	{
+		.ctl_name	= VM_AUTOREGULATE,
+		.procname	= "autoregulate",
+		.data		= &vm_autoregulate,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec,
+	},
 #ifdef CONFIG_HUGETLB_PAGE
 	 {
 		.ctl_name	= VM_HUGETLB_PAGES,
diff -Naurp --exclude-from=/home/con/kernel/dontdiff linux-2.6.7-rc3-base/mm/vmscan.c linux-2.6.7-rc3-as2/mm/vmscan.c
--- linux-2.6.7-rc3-base/mm/vmscan.c	2004-06-10 23:29:04.000000000 +1000
+++ linux-2.6.7-rc3-as2/mm/vmscan.c	2004-06-14 01:40:28.433942581 +1000
@@ -42,7 +42,9 @@
 /*
  * From 0 .. 100.  Higher means more swappy.
  */
-int vm_swappiness = 60;
+int vm_swappiness = 0;
+int vm_autoregulate = 1;
+static int app_percent = 1;
 static long total_memory;
 
 #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
@@ -588,11 +590,13 @@ refill_inactive_zone(struct zone *zone, 
 	LIST_HEAD(l_active);	/* Pages to go onto the active_list */
 	struct page *page;
 	struct pagevec pvec;
-	int reclaim_mapped = 0;
+	int reclaim_mapped = 0;
 	long mapped_ratio;
 	long distress;
 	long swap_tendency;
+	struct sysinfo i;
 
+	si_meminfo(&i);
 	lru_add_drain();
 	pgmoved = 0;
 	spin_lock_irq(&zone->lru_lock);
@@ -635,6 +639,37 @@ refill_inactive_zone(struct zone *zone, 
 	mapped_ratio = (ps->nr_mapped * 100) / total_memory;
 
 	/*
+	 * app_percent is the percentage of physical ram used
+	 * by application pages.
+	 */
+	app_percent = 100 - ((i.freeram + get_page_cache_size() -
+		swapper_space.nrpages) / (i.totalram / 100));
+
+#ifdef CONFIG_SWAP
+	if (vm_autoregulate) {
+		si_swapinfo(&i);
+			
+		if (likely(i.totalswap >= 100)) {
+			int swap_centile;
+	
+			/*
+			 * swap_centile is the percentage of the last (sizeof physical
+			 * ram) of swap free.
+			 */
+			swap_centile = i.freeswap / 
+				(min(i.totalswap, i.totalram) / 100);
+			/*
+			 * Autoregulate vm_swappiness to be equal to the lowest of
+			 * app_percent and swap_centile.  Bias it downwards -ck
+			 */
+			vm_swappiness = min(app_percent, swap_centile);
+			vm_swappiness = vm_swappiness * vm_swappiness / 100;
+		} else 
+			vm_swappiness = 0;
+	}
+#endif
+
+	/*
 	 * Now decide how much we really want to unmap some pages.  The mapped
 	 * ratio is downgraded - just because there's a lot of mapped memory
 	 * doesn't necessarily mean that page reclaim isn't succeeding.
@@ -743,9 +778,13 @@ static int
 shrink_zone(struct zone *zone, int max_scan, unsigned int gfp_mask,
 		int *total_scanned, struct page_state *ps, int do_writepage)
 {
-	unsigned long scan_active;
+	unsigned long scan_active, biased_active;
 	int count;
 
+	if (vm_autoregulate)
+		biased_active = zone->nr_active / (101 - app_percent) * 100;
+	else
+		biased_active = zone->nr_active;
 	/*
 	 * Try to keep the active list 2/3 of the size of the cache.  And
 	 * make sure that refill_inactive is given a decent number of pages.
@@ -756,7 +795,7 @@ shrink_zone(struct zone *zone, int max_s
 	 * `scan_active' just to make sure that the kernel will slowly sift
 	 * through the active list.
 	 */
-	if (zone->nr_active >= 4*(zone->nr_inactive*2 + 1)) {
+	if (biased_active >= 4*(zone->nr_inactive*2 + 1)) {
 		/* Don't scan more than 4 times the inactive list scan size */
 		scan_active = 4*max_scan;
 	} else {
@@ -764,7 +803,7 @@ shrink_zone(struct zone *zone, int max_s
 
 		/* Cast to long long so the multiply doesn't overflow */
 
-		tmp = (unsigned long long)max_scan * zone->nr_active;
+		tmp = (unsigned long long)max_scan * biased_active;
 		do_div(tmp, zone->nr_inactive*2 + 1);
 		scan_active = (unsigned long)tmp;
 	}