Fix zone_reclaim: - PF_SWAPWRITE needs to be set for RECLAIM_SWAP to be able to write out pages to swap. Currently RECLAIM_SWAP may not do that. - remove setting nr_reclaimed pages after slab reclaim since the slab shrinking code does not use that and the nr_reclaimed pages is just right for the intended follow up action. Signed-off-by: Christoph Lameter Index: linux-2.6.16-rc4/mm/vmscan.c =================================================================== --- linux-2.6.16-rc4.orig/mm/vmscan.c 2006-02-17 14:23:45.000000000 -0800 +++ linux-2.6.16-rc4/mm/vmscan.c 2006-02-23 16:28:52.000000000 -0800 @@ -1908,7 +1908,12 @@ int zone_reclaim(struct zone *zone, gfp_ sc.swap_cluster_max = SWAP_CLUSTER_MAX; cond_resched(); - p->flags |= PF_MEMALLOC; + /* + * We need to be able to allocate from the reserves for RECLAIM_SWAP + * and we also need to be able to write out pages for RECLAIM_WRITE + * and RECLAIM_SWAP. + */ + p->flags |= PF_MEMALLOC | PF_SWAPWRITE; reclaim_state.reclaimed_slab = 0; p->reclaim_state = &reclaim_state; @@ -1932,11 +1937,10 @@ int zone_reclaim(struct zone *zone, gfp_ * a long time. */ shrink_slab(sc.nr_scanned, gfp_mask, order); - sc.nr_reclaimed = 1; /* Avoid getting the off node timeout */ } p->reclaim_state = NULL; - current->flags &= ~PF_MEMALLOC; + current->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE); if (sc.nr_reclaimed == 0) zone->last_unsuccessful_zone_reclaim = jiffies;