On Fri, Jun 12, 2015 at 03:05:00PM +0800, Hillf Danton wrote: > > - /* Reclaim above the high watermark. */ > > - sc->nr_to_reclaim = max(SWAP_CLUSTER_MAX, high_wmark_pages(zone)); > > + /* Aim to reclaim above all the zone high watermarks */ > > + for (z = 0; z <= end_zone; z++) { > > + zone = pgdat->node_zones + end_zone; > s/end_zone/z/ ? Ouch, thanks! With this bug, kswapd would reclaim based on a multiple of the highest zone. Whether that was under or over reclaim would depend on the size of that zone relative to lower zones. > > + nr_to_reclaim += high_wmark_pages(zone); > > > [...] > > @@ -3280,13 +3177,26 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order, > > compact_pgdat(pgdat, order); > > > > /* > > + * Stop reclaiming if any eligible zone is balanced and clear > > + * node writeback or congested. > > + */ > > + for (i = 0; i <= *classzone_idx; i++) { > > + zone = pgdat->node_zones + i; > > + > > + if (zone_balanced(zone, sc.order, 0, *classzone_idx)) { > > + clear_bit(PGDAT_CONGESTED, &pgdat->flags); > > + clear_bit(PGDAT_DIRTY, &pgdat->flags); > > + break; > s/break/goto out/ ? Yes. It'd actually be ok because it'll detect the same condition and exit in the next outer loop but goto out is better. -- Mel Gorman 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>