diff options
| author | Rik van Riel <riel@redhat.com> | 2012-03-21 16:33:52 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-21 17:54:56 -0700 |
| commit | aff622495c9a0b56148192e53bdec539f5e147f2 (patch) | |
| tree | 78f6400d8b6bec3279483006a0e9543e47aa833e /mm/compaction.c | |
| parent | 7be62de99adcab4449d416977b4274985c5fe023 (diff) | |
| download | lwn-aff622495c9a0b56148192e53bdec539f5e147f2.tar.gz lwn-aff622495c9a0b56148192e53bdec539f5e147f2.zip | |
vmscan: only defer compaction for failed order and higher
Currently a failed order-9 (transparent hugepage) compaction can lead to
memory compaction being temporarily disabled for a memory zone. Even if
we only need compaction for an order 2 allocation, eg. for jumbo frames
networking.
The fix is relatively straightforward: keep track of the highest order at
which compaction is succeeding, and only defer compaction for orders at
which compaction is failing.
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 36f0f61f4a24..c4b344a95032 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -695,9 +695,19 @@ static int __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc) INIT_LIST_HEAD(&cc->freepages); INIT_LIST_HEAD(&cc->migratepages); - if (cc->order < 0 || !compaction_deferred(zone)) + if (cc->order < 0 || !compaction_deferred(zone, cc->order)) compact_zone(zone, cc); + if (cc->order > 0) { + int ok = zone_watermark_ok(zone, cc->order, + low_wmark_pages(zone), 0, 0); + if (ok && cc->order > zone->compact_order_failed) + zone->compact_order_failed = cc->order + 1; + /* Currently async compaction is never deferred. */ + else if (!ok && cc->sync) + defer_compaction(zone, cc->order); + } + VM_BUG_ON(!list_empty(&cc->freepages)); VM_BUG_ON(!list_empty(&cc->migratepages)); } |