Messages in this thread |  | | | Date | Fri, 3 Apr 2009 09:25:07 +0200 | | From | Jens Axboe <> | | Subject | Re: Linux 2.6.29 |
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On Thu, Apr 02 2009, Linus Torvalds wrote: > > Jens - remind us what the problem with AS was wrt CFQ?
CFQ was just faster, plus it supported things like io priorities that AS does not.
> There's some write throttling in CFQ, maybe it has some really broken > case?
Who knows, it's definitely interesting and something to look into why AS performs that differently to CFQ on his box. Lennart, can you give some information on what file system + mount options, disk drive(s), etc? A full dmesg would be good, too.
> > Linus > > On Fri, 3 Apr 2009, Lennart Sorensen wrote: > > > On Thu, Apr 02, 2009 at 03:00:44AM +0200, Ingo Molnar wrote: > > > I'll test this (and the other suggestions) once i'm out of the merge > > > window. > > > > > > I probably wont test that though ;-) > > > > > > Going back to v2.6.14 to do pre-mutex-merge performance tests was > > > already quite a challenge on modern hardware. > > > > Well after a day of running my mythtv box with anticipatiry rather than > > the default cfq scheduler, it certainly looks a lot better. I haven't > > seen any slowdowns, the disk activity light isn't on solidly (it just > > flashes every couple of seconds instead), and it doesn't even mind > > me lanuching bittornado on multiple torrents at the same time as two > > recordings are taking place and some commercial flagging is taking place. > > With cfq this would usually make the system unusable (and a Q6600 with > > 6GB ram should never be unresponsive in my opinion). > > > > So so far I would rank anticipatory at about 1000x better than cfq for > > my work load. It sure acts a lot more like it used to back in 2.6.18 > > times. > > > > -- > > Len Sorensen > >
-- Jens Axboe
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