diff options
| author | Nick Piggin <npiggin@suse.de> | 2006-09-25 23:31:28 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 08:48:48 -0700 |
| commit | 4ff1ffb4870b007b86f21e5f27eeb11498c4c077 (patch) | |
| tree | f168408f90214873e1fa36733d29f2ba002fae46 | |
| parent | 408d85441cd5a9bd6bc851d677a10c605ed8db5f (diff) | |
| download | lwn-4ff1ffb4870b007b86f21e5f27eeb11498c4c077.tar.gz lwn-4ff1ffb4870b007b86f21e5f27eeb11498c4c077.zip | |
[PATCH] oom: reclaim_mapped on oom
Potentially it takes several scans of the lru lists before we can even start
reclaiming pages.
mapped pages, with young ptes can take 2 passes on the active list + one on
the inactive list. But reclaim_mapped may not always kick in instantly, so it
could take even more than that.
Raise the threshold for marking a zone as all_unreclaimable from a factor of 4
time the pages in the zone to 6. Introduce a mechanism to force
reclaim_mapped if we've reached a factor 3 and still haven't made progress.
Previously, a customer doing stress testing was able to easily OOM the box
after using only a small fraction of its swap (~100MB). After the patches, it
would only OOM after having used up all swap (~800MB).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | mm/vmscan.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index ba18d0c36b83..8f35d7d585cb 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -697,6 +697,11 @@ done: return nr_reclaimed; } +static inline int zone_is_near_oom(struct zone *zone) +{ + return zone->pages_scanned >= (zone->nr_active + zone->nr_inactive)*3; +} + /* * This moves pages from the active list to the inactive list. * @@ -732,6 +737,9 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, long distress; long swap_tendency; + if (zone_is_near_oom(zone)) + goto force_reclaim_mapped; + /* * `distress' is a measure of how much trouble we're having * reclaiming pages. 0 -> no problems. 100 -> great trouble. @@ -767,6 +775,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, * memory onto the inactive list. */ if (swap_tendency >= 100) +force_reclaim_mapped: reclaim_mapped = 1; } @@ -1161,7 +1170,7 @@ scan: if (zone->all_unreclaimable) continue; if (nr_slab == 0 && zone->pages_scanned >= - (zone->nr_active + zone->nr_inactive) * 4) + (zone->nr_active + zone->nr_inactive) * 6) zone->all_unreclaimable = 1; /* * If we've done a decent amount of scanning and |