> From: Minchan Kim <minchan.kim@xxxxxxxxx> > Date: Mon, 23 Aug 2010 00:20:44 +0900 > Subject: [PATCH] compaction: handle active and inactive fairly in too_many_isolated > > Iram reported compaction's too_many_isolated loops forever. > (http://www.spinics.net/lists/linux-mm/msg08123.html) > > The meminfo of situation happened was inactive anon is zero. > That's because the system has no memory pressure until then. > While all anon pages was in active lru, compaction could select > active lru as well as inactive lru. That's different things > with vmscan's isolated. So we has been two too_many_isolated. > > While compaction can isolated pages in both active and inactive, > current implementation of too_many_isolated only considers inactive. > It made Iram's problem. > > This patch handles active and inactie with fair. > That's because we can't expect where from and how many compaction would > isolated pages. > > This patch changes (nr_isolated > nr_inactive) with > nr_isolated > (nr_active + nr_inactive) / 2. The change looks good, thanks. However I'm not sure if it's enough. I wonder where the >40MB isolated pages come about. inactive_anon remains 0 and free remains high over a long time, so it seems there are no concurrent direct reclaims at all. Are the pages isolated by the compaction process itself? Thanks, Fengguang -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>