linux-kernel - Re: Linux 2.6.29

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 3 Apr 2009 09:25:07 +0200
From:	Jens Axboe <jens.axboe@...cle.com>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Lennart Sorensen <lsorense@...lub.uwaterloo.ca>,
	Ingo Molnar <mingo@...e.hu>,
	Andrew Morton <akpm@...ux-foundation.org>, tytso@....edu,
	drees76@...il.com, jesper@...gh.cc,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: Linux 2.6.29

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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/