On Sun 17-03-13 13:04:07, Mel Gorman wrote: [...] > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 88c5fed..4835a7a 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2593,6 +2593,32 @@ static bool prepare_kswapd_sleep(pg_data_t *pgdat, int order, long remaining, > } > > /* > + * kswapd shrinks the zone by the number of pages required to reach > + * the high watermark. > + */ > +static void kswapd_shrink_zone(struct zone *zone, > + struct scan_control *sc, > + unsigned long lru_pages) > +{ > + unsigned long nr_slab; > + struct reclaim_state *reclaim_state = current->reclaim_state; > + struct shrink_control shrink = { > + .gfp_mask = sc->gfp_mask, > + }; > + > + /* Reclaim above the high watermark. */ > + sc->nr_to_reclaim = max(SWAP_CLUSTER_MAX, high_wmark_pages(zone)); OK, so the cap is at high watermark which sounds OK to me, although I would expect balance_gap being considered here. Is it not used intentionally or you just wanted to have a reasonable upper bound? I am not objecting to that it just hit my eyes. > + shrink_zone(zone, sc); > + > + reclaim_state->reclaimed_slab = 0; > + nr_slab = shrink_slab(&shrink, sc->nr_scanned, lru_pages); > + sc->nr_reclaimed += reclaim_state->reclaimed_slab; > + > + if (nr_slab == 0 && !zone_reclaimable(zone)) > + zone->all_unreclaimable = 1; > +} > + > +/* > * For kswapd, balance_pgdat() will work across all this node's zones until > * they are all at high_wmark_pages(zone). > * -- Michal Hocko SUSE Labs -- 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>