From: Christoph Lameter Minor performance fix. If we reclaimed enough slab pages from a zone then we can avoid going off node with the current allocation. Take care of updating nr_reclaimed when reclaiming from the slab. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton --- mm/vmscan.c | 17 ++++++++++++----- 1 files changed, 12 insertions(+), 5 deletions(-) diff -puN mm/vmscan.c~zone-reclaim-with-slab-avoid-unecessary-off-node-allocations mm/vmscan.c --- a/mm/vmscan.c~zone-reclaim-with-slab-avoid-unecessary-off-node-allocations +++ a/mm/vmscan.c @@ -1566,6 +1566,7 @@ static int __zone_reclaim(struct zone *z .gfp_mask = gfp_mask, .swappiness = vm_swappiness, }; + unsigned long slab_reclaimable; disable_swap_token(); cond_resched(); @@ -1592,7 +1593,8 @@ static int __zone_reclaim(struct zone *z } while (priority >= 0 && nr_reclaimed < nr_pages); } - if (zone_page_state(zone, NR_SLAB_RECLAIMABLE) > zone->min_slab_pages) { + slab_reclaimable = zone_page_state(zone, NR_SLAB_RECLAIMABLE); + if (slab_reclaimable > zone->min_slab_pages) { /* * shrink_slab() does not currently allow us to determine how * many pages were freed in this zone. So we take the current @@ -1603,12 +1605,17 @@ static int __zone_reclaim(struct zone *z * Note that shrink_slab will free memory on all zones and may * take a long time. */ - unsigned long limit = zone_page_state(zone, - NR_SLAB_RECLAIMABLE) - nr_pages; - while (shrink_slab(sc.nr_scanned, gfp_mask, order) && - zone_page_state(zone, NR_SLAB_RECLAIMABLE) > limit) + zone_page_state(zone, NR_SLAB_RECLAIMABLE) > + slab_reclaimable - nr_pages) ; + + /* + * Update nr_reclaimed by the number of slab pages we + * reclaimed from this zone. + */ + nr_reclaimed += slab_reclaimable - + zone_page_state(zone, NR_SLAB_RECLAIMABLE); } p->reclaim_state = NULL; _