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/page_alloc.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/page_alloc.c')
-rw-r--r-- | mm/page_alloc.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a13ded1938f0..572b93ea475c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1990,7 +1990,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, if (!order) return NULL; - if (compaction_deferred(preferred_zone)) { + if (compaction_deferred(preferred_zone, order)) { *deferred_compaction = true; return NULL; } @@ -2012,6 +2012,8 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, if (page) { preferred_zone->compact_considered = 0; preferred_zone->compact_defer_shift = 0; + if (order >= preferred_zone->compact_order_failed) + preferred_zone->compact_order_failed = order + 1; count_vm_event(COMPACTSUCCESS); return page; } @@ -2028,7 +2030,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, * defer if the failure was a sync compaction failure. */ if (sync_migration) - defer_compaction(preferred_zone); + defer_compaction(preferred_zone, order); cond_resched(); } |