On Wed, Oct 31, 2012 at 12:25:13PM +0100, Thorsten Leemhuis wrote: > On 30.10.2012 20:18, Mel Gorman wrote: > >On Mon, Oct 29, 2012 at 11:52:03AM +0100, Thorsten Leemhuis wrote: > >>On 15.10.2012 13:09, Mel Gorman wrote: > >>>On Mon, Oct 15, 2012 at 11:54:13AM +0200, Jiri Slaby wrote: > >>>>On 10/12/2012 03:57 PM, Mel Gorman wrote: > >>>>>mm: vmscan: scale number of pages reclaimed by reclaim/compaction only in direct reclaim > >>>>>Jiri Slaby reported the following: > >[...] > >>>>Yes, applying this instead of the revert fixes the issue as well. > >>Just wondering, is there a reason why this patch wasn't applied to > >>mainline? Did it simply fall through the cracks? Or am I missing > >>something? > >It's because a problem was reported related to the patch (off-list, > >whoops). I'm waiting to hear if a second patch fixes the problem or not. > > Anything in particular I should look out for while testing? > Excessive reclaim, high CPU usage by kswapd, processes getting stick in isolate_migratepages or isolate_freepages. > >>I'm asking because I think I stil see the issue on > >>3.7-rc2-git-checkout-from-friday. Seems Fedora rawhide users are > >>hitting it, too: > >>https://bugzilla.redhat.com/show_bug.cgi?id=866988 > >I like the steps to reproduce. > > One of those cases where the bugzilla bug template was not very > helpful or where it was not used as intended (you decide) :-) > It wins at entertainment value if nothing else :) > >Is step 3 profit? > > Yes, but psst, don't tell anyone; step 4 (world domination! for > real!) is also hidden to keep that part of the big plan a secret for > now ;-) > No doubt it's the default private comment #1 ! > >>Or are we seeing something different which just looks similar? I can > >>test the patch if it needs further testing, but from the discussion > >>I got the impression that everything is clear and the patch ready > >>for merging. > >It could be the same issue. Can you test with the "mm: vmscan: scale > >number of pages reclaimed by reclaim/compaction only in direct reclaim" > >patch and the following on top please? > > Built a vanilla mainline kernel with those two patches and installed > it on the machine where I was seeing problems high kswapd0 load on > 3.7-rc3. Ran it an hour yesterday and a few hours today; seems the > patches fix the issue for me as kswapd behaves: > > $ LC_ALL=C ps -aux | grep 'kswapd' > root 62 0.0 0.0 0 0 ? S Oct30 0:05 [kswapd0] > > So everything is looking fine again so far thx to the two patches > -- hopefully it stays that way even after hitting "send" in my > mailer in a few seconds. > Ok, great. Keep an eye on it please. If Jiri Slaby reports similar success then I'll collapse the two patches together and resend to Andrew. Thanks. -- 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>