On Thu, Apr 28, 2011 at 06:10:46PM +0900, KAMEZAWA Hiroyuki wrote: > On Thu, 28 Apr 2011 10:54:32 +0200 > Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > > On Wed, Apr 27, 2011 at 05:03:04PM +0900, KAMEZAWA Hiroyuki wrote: > > > On Wed, 27 Apr 2011 01:25:20 +0900 > > > Minchan Kim <minchan.kim@xxxxxxxxx> wrote: > > > > > > > In some __zone_reclaim case, we don't want to shrink mapped page. > > > > Nonetheless, we have isolated mapped page and re-add it into > > > > LRU's head. It's unnecessary CPU overhead and makes LRU churning. > > > > > > > > Of course, when we isolate the page, the page might be mapped but > > > > when we try to migrate the page, the page would be not mapped. > > > > So it could be migrated. But race is rare and although it happens, > > > > it's no big deal. > > > > > > > > Cc: Christoph Lameter <cl@xxxxxxxxx> > > > > Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > > > > Cc: Mel Gorman <mgorman@xxxxxxx> > > > > Cc: Rik van Riel <riel@xxxxxxxxxx> > > > > Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> > > > > Signed-off-by: Minchan Kim <minchan.kim@xxxxxxxxx> > > > > > > > > > Hmm, it seems mm/memcontrol.c::mem_cgroup_isolate_pages() should be updated, too. > > > > memcg reclaim always does sc->may_unmap = 1. What is there to > > communicate to mem_cgroup_isolate_pages? > > > > Hmm, maybe you're right and nothing to do until memcg need to support soft > limit in zone reclaim mode. I hope no more users. Ah, okay. I thought I may have missed something. Thanks for the clarification, Kame. Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx 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=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>