linux-kernel - Re: iozone write 50% regression in kernel 2.6.24-rc1

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:	Mon, 12 Nov 2007 10:45:28 +0100
From:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
To:	"Zhang, Yanmin" <yanmin_zhang@...ux.intel.com>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: Re: iozone write 50% regression in kernel 2.6.24-rc1


On Mon, 2007-11-12 at 10:14 +0800, Zhang, Yanmin wrote:

> > Subject: mm: speed up writeback ramp-up on clean systems
>
> I tested kernel 2.6.23, 2,6,24-rc2, 2.6.24-rc2_peter(2.6.24-rc2+this patch).
> 
> 1) Compare among first/second/following running
> 2.6.23: second run of iozone will get about 28% improvement than first run.
> 	Following run is very stable like 2nd run.
> 2.6.24-rc2: second run of iozone will get about 170% improvement than first run. 3rd run
> 	will get about 80% improvement than 2nd. Following run is very stable like 3rd run.
> 2.6.24-rc2_peter: second run of iozone will get about 14% improvement than first run. Following
> 	run is mostly stable like 2nd run.
> So the new patch really improves the first run result. Comparing wiht 2.6.24-rc2, 2.6.24-rc2_peter
> has 330% improvement on the first run.
> 
> 2) Compare among different kernels(based on the stable highest result):
> 2.6.24-rc2 has about 50% regression than 2.6.23.
> 2.6.24-rc2_peter has the same result like 2.6.24-rc2.
>
> From this point of view, above patch has no improvement. :)

Drad, still good test results though.

Could you describe you system in detail, that is, you have 8GB of memory
and 8 cpus (2*quad?). How many disks does it have and are those
aggregated using md or dm? What filesystem do you use?



Download attachment "signature.asc" of type "application/pgp-signature" (190 bytes)