On Sun, Jan 22, 2012 at 5:55 PM, Hillf Danton <dhillf@xxxxxxxxx> wrote: > To avoid reduction in performance of reclaimee, checking overreclaim is added > after shrinking lru list, when pages are reclaimed from mem cgroup. > > If over reclaim occurs, shrinking remaining lru lists is skipped, and no more > reclaim for reclaim/compaction. > > Signed-off-by: Hillf Danton <dhillf@xxxxxxxxx> > --- > > --- a/mm/vmscan.c Mon Jan 23 00:23:10 2012 > +++ b/mm/vmscan.c Mon Jan 23 09:57:20 2012 > @@ -2086,6 +2086,7 @@ static void shrink_mem_cgroup_zone(int p > unsigned long nr_reclaimed, nr_scanned; > unsigned long nr_to_reclaim = sc->nr_to_reclaim; > struct blk_plug plug; > + bool memcg_over_reclaimed = false; > > restart: > nr_reclaimed = 0; > @@ -2103,6 +2104,11 @@ restart: > > nr_reclaimed += shrink_list(lru, nr_to_scan, > mz, sc, priority); > + > + memcg_over_reclaimed = !scanning_global_lru(mz) > + && (nr_reclaimed >= nr_to_reclaim); > + if (memcg_over_reclaimed) > + goto out; Why we need the change here? Do we have number to demonstrate? > } > } > /* > @@ -2116,6 +2122,7 @@ restart: > if (nr_reclaimed >= nr_to_reclaim && priority < DEF_PRIORITY) > break; > } > +out: > blk_finish_plug(&plug); > sc->nr_reclaimed += nr_reclaimed; > > @@ -2127,7 +2134,8 @@ restart: > shrink_active_list(SWAP_CLUSTER_MAX, mz, sc, priority, 0); > > /* reclaim/compaction might need reclaim to continue */ > - if (should_continue_reclaim(mz, nr_reclaimed, > + if (!memcg_over_reclaimed && > + should_continue_reclaim(mz, nr_reclaimed, > sc->nr_scanned - nr_scanned, sc)) This changes the existing logic. What if the nr_reclaimed is greater than nr_to_reclaim, but smaller than pages_for_compaction? The existing logic is to continue reclaiming. --Ying > goto restart; -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href