Mel Gorman wrote on 28.11.2012 11:13: > On Tue, Nov 27, 2012 at 03:19:38PM -0800, Linus Torvalds wrote: >> On Tue, Nov 27, 2012 at 2:26 PM, Johannes Weiner <hannes@xxxxxxxxxxx> wrote: >> > On Tue, Nov 27, 2012 at 05:02:36PM -0500, Rik van Riel wrote: > >> And the one who comes out gets to explain to me which patch(es) I >> should apply, and which I should revert, if any. > > Based on the reports I've seen I expect the following to work for 3.7 > > Keep > 96710098 mm: revert "mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures" > ef6c5be6 fix incorrect NR_FREE_PAGES accounting (appears like memory leak) > > Revert > 82b212f4 Revert "mm: remove __GFP_NO_KSWAPD" > > Merge > mm: vmscan: fix kswapd endless loop on higher order allocation > mm: Avoid waking kswapd for THP allocations when compaction is deferred or contended I'll build a kernel with this combination and will give it a try. Maybe one of those people that reported problems in https://bugzilla.redhat.com/show_bug.cgi?id=866988 can try them, too. There two people recently reported their problems were gone with kernels that contained 82b212f4. > Johannes' patch should remove the necessity for __GFP_NO_KSWAPD revert but I > think we should also avoid waking kswapd for THP allocations if compaction > is deferred. Johannes' patch might mean that kswapd goes quickly go back > to sleep but it's still busy work. Is there a way to trigger (some benchmark?) and detect (something in /proc/vmstat ?) the problem Hannes patch tries to fix? Background: The two main problems that got me into this discussion vanished thx to 9671009 (mm: revert "mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures") and ef6c5be (fix incorrect NR_FREE_PAGES accounting (appears like memory leak)). I thought all my problems had gone, but after a few days of uptime (suspended and resumed the particular machine a few times in between, as I was using it just in the evenings) kswap now and then started consuming nearly 100% of one cpu core for 10 to 15 seconds intervals (it seems watching a YouTube video triggered it; and the machine was using a little bit swap space). I just had started debugging this, but due to some stupid mistake (https://plus.google.com/107616711159256259828/posts/GXuhf1LTien ) then rebooted the machine :-/ So maybe I hit the problem Hannes patch tries to solve, but I'm not sure; and I have no easy way to verify quickly if the proposed patch combination helps. Thorsten -- 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>