Re: [PATCH] - Taming OOM killer, 2.4.17-rc1

["M.H.VanLeeuwen" <vanl@megsinet.net>]

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Denis,

This patch was a feeble attempt at fixing a real VM problem by masking what was
really going on.

There are many "better" solution than this old patch

AA has a great VM patch
Rik has an rmap patch that looks promising

and my latest "simple" fix is attached for 2.4.17 but should apply to 2.4.18-pre

Thanks for looking at this old one though.

Martin

BTW: w/ this patch you no longer need to Tame the OOM killer

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--- linux.virgin/mm/vmscan.c	Mon Dec 31 12:46:25 2001
+++ linux/mm/vmscan.c	Fri Jan 11 18:03:05 2002
@@ -394,9 +394,9 @@
 		if (PageDirty(page) && is_page_cache_freeable(page) && page->mapping) {
 			/*
 			 * It is not critical here to write it only if
-			 * the page is unmapped beause any direct writer
+			 * the page is unmapped because any direct writer
 			 * like O_DIRECT would set the PG_dirty bitflag
-			 * on the phisical page after having successfully
+			 * on the physical page after having successfully
 			 * pinned it and after the I/O to the page is finished,
 			 * so the direct writes to the page cannot get lost.
 			 */
@@ -480,11 +480,14 @@
 
 			/*
 			 * Alert! We've found too many mapped pages on the
-			 * inactive list, so we start swapping out now!
+			 * inactive list.
+			 * Move referenced pages to the active list.
 			 */
-			spin_unlock(&pagemap_lru_lock);
-			swap_out(priority, gfp_mask, classzone);
-			return nr_pages;
+			if (PageReferenced(page) && !PageLocked(page)) {
+				del_page_from_inactive_list(page);
+				add_page_to_active_list(page);
+			}
+			continue;
 		}
 
 		/*
@@ -521,6 +524,9 @@
 	}
 	spin_unlock(&pagemap_lru_lock);
 
+	if (max_mapped <= 0 && (nr_pages > 0 || priority < DEF_PRIORITY))
+		swap_out(priority, gfp_mask, classzone);
+
 	return nr_pages;
 }