If allocation fails after compaction then compaction may be deferred for a number of allocation attempts. If there are subsequent failures, compact_defer_shift is increased to defer for longer periods. This patch uses that information to scale the number of pages reclaimed with compact_defer_shift until allocations succeed again.
Signed-off-by: Mel Gorman <mgor...@suse.de> Acked-by: Rik van Riel <r...@redhat.com> --- mm/vmscan.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/mm/vmscan.c b/mm/vmscan.c index 66e4310..0cb2593 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1708,6 +1708,7 @@ static inline bool should_continue_reclaim(struct lruvec *lruvec, { unsigned long pages_for_compaction; unsigned long inactive_lru_pages; + struct zone *zone; /* If not in reclaim/compaction mode, stop */ if (!in_reclaim_compaction(sc)) @@ -1741,6 +1742,15 @@ static inline bool should_continue_reclaim(struct lruvec *lruvec, * inactive lists are large enough, continue reclaiming */ pages_for_compaction = (2UL << sc->order); + + /* + * If compaction is deferred for this order then scale the number of + * pages reclaimed based on the number of consecutive allocation + * failures + */ + zone = lruvec_zone(lruvec); + if (zone->compact_order_failed >= sc->order) + pages_for_compaction <<= zone->compact_defer_shift; inactive_lru_pages = get_lru_size(lruvec, LRU_INACTIVE_FILE); if (nr_swap_pages > 0) inactive_lru_pages += get_lru_size(lruvec, LRU_INACTIVE_ANON); -- 1.7.9.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/