Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932096Ab1BXBkx (ORCPT ); Wed, 23 Feb 2011 20:40:53 -0500 Received: from ipmail06.adl6.internode.on.net ([150.101.137.145]:22196 "EHLO ipmail06.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754228Ab1BXBkw (ORCPT ); Wed, 23 Feb 2011 20:40:52 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AvsEAM9EZU120uZw/2dsb2JhbACmHnS8FYVeBJFt Message-ID: <4D65B71D.5030109@internode.on.net> Date: Thu, 24 Feb 2011 12:10:45 +1030 From: Arthur Marsh User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-AU; rv:1.9.2.13) Gecko/20101213 Icedove/3.1.7 MIME-Version: 1.0 To: Andrea Arcangeli CC: Clemens Ladisch , alsa-user@lists.sourceforge.net, linux-kernel@vger.kernel.org, Mel Gorman Subject: Re: [Alsa-user] new source of MIDI playback slow-down identified - 5a03b051ed87e72b959f32a86054e1142ac4cf55 thp: use compaction in kswapd for GFP_ATOMIC order > 0 References: <4D6367B3.9050306@googlemail.com> <20110222134047.GT13092@random.random> <20110222161513.GC13092@random.random> <4D63F6C0.7060204@internode.on.net> <20110223162432.GL31195@random.random> <20110223165550.GP31195@random.random> <4D65691E.9080600@internode.on.net> <20110223212541.GV31195@random.random> <4D65825F.5080403@internode.on.net> <20110223235946.GW31195@random.random> In-Reply-To: <20110223235946.GW31195@random.random> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1583 Lines: 37 Andrea Arcangeli wrote, on 24/02/11 10:29: > On Thu, Feb 24, 2011 at 08:25:43AM +1030, Arthur Marsh wrote: >> One more combination I tried: >> >> Mel Gorman's mm/compaction.c patch with Andrea Archangeli's >> kswapd-high_wmark + compaction-no-kswapd-3 patches - kswapd0 CPU less >> than 2 percent and no noticable slowdown of MIDI playback. > > Applying Mel's patch on top should decrease latency more. > >> If you can send me an updated patch compaction-no-kswapd-3 (I presume >> that kswapd-high_wmark is still needed) it would be easier for me to apply. > > It's a compaction-kswapd-3. It's likely going to work the same as the > previous compaction-kswapd-2 (not as good as > compaction-no-kswapd). It's better to apply both the kswapd-high_wmark > and Mel's patch too (not only this one) during testing. OK, with kswapd-high_wmark + compaction-kswapd-3 + Mel's patch (with the compaction initialisation fix), MIDI playback is fine. kswapd0 CPU can very occasionally hit equal highest (17 percent was the highest I noticed, but is generally below the top 4-5 processes and less than 10 percent when working, dropping to around 0.3 percent when swap activity has subsided). This was with loading KDE 3.5.10, konversation, aptitude -u, icedove and iceweasel with several dozen tabs in addition to aplaymidi. Regards, Arthur. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/