Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 16 Feb 2003 01:09:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 16 Feb 2003 01:09:56 -0500 Received: from imap.gmx.net ([213.165.64.20]:16017 "HELO mail.gmx.net") by vger.kernel.org with SMTP id ; Sun, 16 Feb 2003 01:09:54 -0500 Message-Id: <5.1.1.6.2.20030216071717.00cc7818@pop.gmx.net> X-Mailer: QUALCOMM Windows Eudora Version 5.1.1 Date: Sun, 16 Feb 2003 07:24:27 +0100 To: Jens Axboe , Rik van Riel From: Mike Galbraith Subject: Re: [PATCH] CFQ scheduler, #2 Cc: Linux Kernel In-Reply-To: <20030215163550.GO26738@suse.de> References: <5.1.1.6.2.20030215105330.00c84da8@pop.gmx.net> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=====================_9453453==_" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4393 Lines: 87 --=====================_9453453==_ Content-Type: text/plain; charset="us-ascii"; format=flowed At 05:35 PM 2/15/2003 +0100, Jens Axboe wrote: >On Sat, Feb 15 2003, Rik van Riel wrote: > > On Sat, 15 Feb 2003, Mike Galbraith wrote: > > > > >I gave this a burn, and under hefty load it seems to provide a bit of > > >anti-thrash benefit. > > > > Judging from your log, it ends up stalling kswapd and > > dramatically increases the number of times that normal > > processes need to go into the pageout code. > >With 30 odds processes, it doesn't take a whole lot for one process to >have its share of requests eaten. > > > If this provides an anti-thrashing benefit, something's > > wrong with the VM in 2.5 ;) > >It's not a vm problem. But it is a problem if kswapd + pdflush can >consume the entire request pool, stalling real user processes. > >Mike, please retry the test with more requests available. CFQ does not >rely on request queue length for fairness. Just changes: > > (queue_nr_requests > 128) > queue_nr_requests = 128; > >to > > (queue_nr_requests > 512) > queue_nr_requests = 512; > >in ll_rw_blk.c:blk_dev_init() and see how that runs. Results attached. 512 comes out to be 240 on this box (128MB). I also did a burn with it hardwired to 512 on GP. Throughput numbers cut since there's all within expected jitter. -Mike --=====================_9453453==_ Content-Type: text/plain; name="xx.txt"; x-mac-type="42494E41"; x-mac-creator="74747874" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="xx.txt" L3Byb2Mvdm1zdGF0IDIuNS42MWNmcTIgICAyLjUuNjF2aXJnaW4gIGNmcTItNTEyKDI0MCkgICAg Y2ZxMi01MTIKLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0t LS0tLS0tLS0tLS0tLS0tLS0KbnJfZGlydHkgICAgICAgICAgICAgMjAgICAgICAgICAgICAgMTMg ICAgICAgICAgICAgOSAgICAgICAgICAgMTIKbnJfd3JpdGViYWNrICAgICAgICAgIDAgICAgICAg ICAgICAgIDAgICAgICAgICAgICAgMCAgICAgICAgICAgIDAKbnJfcGFnZWNhY2hlICAgICAgIDcz MDggICAgICAgICAgIDc1OTMgICAgICAgICAgNzE3NiAgICAgICAgIDc3MzcKbnJfcGFnZV90YWJs ZV9wYWdlcyAgODUgICAgICAgICAgICAgODUgICAgICAgICAgICA4NSAgICAgICAgICAgODUKbnJf cmV2ZXJzZV9tYXBzICAgIDMyMjkgICAgICAgICAgIDMxOTggICAgICAgICAgMzI1NCAgICAgICAg IDMxNTkKbnJfbWFwcGVkICAgICAgICAgICA1OTkgICAgICAgICAgICA1OTkgICAgICAgICAgIDYw OCAgICAgICAgICA1ODMKbnJfc2xhYiAgICAgICAgICAgIDEyMDMgICAgICAgICAgIDExODQgICAg ICAgICAgMTE2OSAgICAgICAgIDEyMzcKcGdwZ2luICAgICAgICAgIDE3Njc0MzIgICAgICAgIDE5 MTE2MTQgICAgICAgMTc1ODUwMSAgICAgIDE3NzU0MDIKcGdwZ291dCAgICAgICAgIDE2MDY3NDMg ICAgICAgIDE3NDY0OTcgICAgICAgMTU5NTkyMCAgICAgIDE2NTQzNjYKcHN3cGluICAgICAgICAg ICAzMTEyOTcgICAgICAgICAzMzg0MzYgICAgICAgIDMwNzgxMSAgICAgICAzMTE1MTUKcHN3cG91 dCAgICAgICAgICAzNzExNjEgICAgICAgICA0MDY2NzUgICAgICAgIDM2OTEzMiAgICAgICAzODMz MDIKcGdhbGxvYyAgICAgICAgIDMwMzc5NjEgICAgICAgIDMwNzA4MTEgICAgICAgMzAzMDQ4MiAg ICAgIDMwMjA5NjYKcGdmcmVlICAgICAgICAgIDMwNjA4MjUgICAgICAgIDMwOTM0MjAgICAgICAg MzA1MzUyNCAgICAgIDMwNDMzNTUKcGdhY3RpdmF0ZSAgICAgICAxNDIzMjkgICAgICAgICAxMzU2 MTYgICAgICAgIDEzNDk2OCAgICAgICAxMzY2NTUKcGdkZWFjdGl2YXRlICAgICA1MTQ2NzIgICAg ICAgICA1MDcwMjYgICAgICAgIDQ4MTE1NiAgICAgICA1MDExMTEKcGdmYXVsdCAgICAgICAgIDQ4 OTY4NzcgICAgICAgIDQ5Mjg1MzAgICAgICAgNDg5MTk4NyAgICAgIDQ5MTM1OTQKcGdtYWpmYXVs dCAgICAgICAgNzQzNDIgICAgICAgICAgODQ0NzYgICAgICAgICA3NDA1OCAgICAgICAgODI4NTcK cGdzY2FuICAgICAgICAgIDI3NTE5NTMgICAgICAgIDUzMjgyNjAgICAgICAgMzI1MDg4MCAgICAg IDM3OTc5MTkKcGdyZWZpbGwgICAgICAgIDE4MjE1NjEgICAgICAgIDE5NzI3MTUgICAgICAgMTg5 NjExOSAgICAgIDIwNTc0NjEKcGdzdGVhbCAgICAgICAgICA1MjgwMTQgICAgICAgICA1NzUzMDEg ICAgICAgIDUyODUxMyAgICAgICA1MjkwMTEKcGdpbm9kZXN0ZWFsICAgICAgICAgIDAgICAgICAg ICAgICAgIDAgICAgICAgICAgICAgMCAgICAgICAgICAgIDAKa3N3YXBkX3N0ZWFsICAgICAzODAy ODIgICAgICAgICA1MjIxMjYgICAgICAgIDQwNTA3OCAgICAgICA0MTAzODIKa3N3YXBkX2lub2Rl c3RlYWwgIDcwMTAgICAgICAgICAgIDcxMzIgICAgICAgICAgNjcwNCAgICAgICAgIDY4MjkKcGFn ZW91dHJ1biAgICAgICAgIDExMDcgICAgICAgICAgIDE5NTYgICAgICAgICAgMTI2MyAgICAgICAg IDEyNTkKYWxsb2NzdGFsbCAgICAgICAgIDM0NzIgICAgICAgICAgIDEyMzggICAgICAgICAgMjg2 NSAgICAgICAgIDI3ODIKcGdyb3RhdGVkICAgICAgICAzNTgyNDMgICAgICAgICA0MTM0NTAgICAg ICAgIDM2NTkxNCAgICAgICAzODcyNzcKCg== --=====================_9453453==_-- - 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/