From adea02a1bea71a508da32c04d715485a1fe62029 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Mon, 21 Sep 2009 17:01:42 -0700 Subject: mm: count only reclaimable lru pages global_lru_pages() / zone_lru_pages() can be used in two ways: - to estimate max reclaimable pages in determine_dirtyable_memory() - to calculate the slab scan ratio When swap is full or not present, the anon lru lists are not reclaimable and also won't be scanned. So the anon pages shall not be counted in both usage scenarios. Also rename to _reclaimable_pages: now they are counting the possibly reclaimable lru pages. It can greatly (and correctly) increase the slab scan rate under high memory pressure (when most file pages have been reclaimed and swap is full/absent), thus reduce false OOM kills. Acked-by: Peter Zijlstra Reviewed-by: Rik van Riel Reviewed-by: Christoph Lameter Reviewed-by: Minchan Kim Cc: KOSAKI Motohiro Signed-off-by: Wu Fengguang Acked-by: Johannes Weiner Reviewed-by: Minchan Kim Reviewed-by: Jesse Barnes Cc: David Howells Cc: "Li, Ming Chun" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page-writeback.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index d1ba46441053..5f378dd58802 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -380,7 +380,8 @@ static unsigned long highmem_dirtyable_memory(unsigned long total) struct zone *z = &NODE_DATA(node)->node_zones[ZONE_HIGHMEM]; - x += zone_page_state(z, NR_FREE_PAGES) + zone_lru_pages(z); + x += zone_page_state(z, NR_FREE_PAGES) + + zone_reclaimable_pages(z); } /* * Make sure that the number of highmem pages is never larger @@ -404,7 +405,7 @@ unsigned long determine_dirtyable_memory(void) { unsigned long x; - x = global_page_state(NR_FREE_PAGES) + global_lru_pages(); + x = global_page_state(NR_FREE_PAGES) + global_reclaimable_pages(); if (!vm_highmem_is_dirtyable) x -= highmem_dirtyable_memory(x); -- cgit v1.2.3-55-g7522