If we're in the fast path and we succeeded zone_reclaim(), it means we freed enough memory and we can use the min watermark to have some margin against concurrent allocations from other CPUs or interrupts. Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> --- mm/page_alloc.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0519181..3690c2e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1961,8 +1961,26 @@ zonelist_scan: case ZONE_RECLAIM_FULL: /* scanned but unreclaimable */ continue; + case ZONE_RECLAIM_SUCCESS: + /* + * If we successfully reclaimed + * enough, allow allocations up to the + * min watermark (instead of stopping + * at "mark"). This provides some more + * margin against parallel + * allocations. Using the min + * watermark doesn't alter when we + * wakeup kswapd. It also doesn't + * alter the synchronous direct + * reclaim behavior of zone_reclaim() + * that will still be invoked at the + * next pass if we're still below the + * low watermark (even if kswapd isn't + * woken). + */ + mark = min_wmark_pages(zone); + /* Fall through */ default: - /* did we reclaim enough */ if (zone_watermark_ok(zone, order, mark, classzone_idx, alloc_flags)) goto try_this_zone; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>