[PATCH] high/low water mark -- correct

[Rik van Riel <H.H.vanRiel@phys.uu.nl>]

Hi Linus,

after doing some arithmetic, I decided that the previous
patch was a little too much for small systems...
Please apply this one instead.

I will change the freepages struct to use these values
RSN...

Rik.
+-------------------------------------------+--------------------------+
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+-------------------------------------------+--------------------------+

--- linux/mm/page_alloc.c.2196	Tue Apr 14 23:27:23 1998
+++ linux/mm/page_alloc.c	Wed Apr 15 02:04:39 1998
@@ -134,8 +134,9 @@
 	 * It may not be, due to fragmentation, but we
 	 * don't want to keep on forever trying to find
 	 * free unfragmented memory.
+	 * Added low/high water marks to avoid thrashing -- Rik.
 	 */
-	if (nr_free_pages > num_physpages >> 4)
+	if (nr_free_pages > (num_physpages >> 5) + (nr ? 0 : SWAP_CLUSTER_MAX))
 		return nr+1;
 
 	list = free_area + NR_MEM_LISTS;