linux-kernel - Re: huge improvement with per-device dirty throttling

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Tue, 04 Sep 2007 11:37:36 +0200
From:	Leroy van Logchem <leroy.vanlogchem@...elft.nl>
To:	Andrea Arcangeli <andrea@...e.de>
CC:	Andi Kleen <andi@...stfloor.org>,
	"Jeffrey W. Baker" <jwbaker@....org>, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org
Subject: Re: huge improvement with per-device dirty throttling

Andrea Arcangeli wrote:
> On Wed, Aug 22, 2007 at 01:05:13PM +0200, Andi Kleen wrote:
>> Ok perhaps the new adaptive dirty limits helps your single disk
>> a lot too. But your improvements seem to be more "collateral damage" @)
>>
>> But if that was true it might be enough to just change the dirty limits
>> to get the same effect on your system. You might want to play with
>> /proc/sys/vm/dirty_*
> 
> The adaptive dirty limit is per task so it can't be reproduced with
> global sysctl. It made quite some difference when I researched into it
> in function of time. This isn't in function of time but it certainly
> makes a lot of difference too, actually it's the most important part
> of the patchset for most people, the rest is for the corner cases that
> aren't handled right currently (writing to a slow device with
> writeback cache has always been hanging the whole thing).


Self-tuning > static sysctl's. The last years we needed to use very 
small values for dirty_ratio and dirty_background_ratio to soften the 
latency problems we have during sustained writes. Imo these patches 
really help in many cases, please commit to mainline.

-- 
Leroy
-
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/