From: Gordon Ross (G.Ross_at_ccw.gov.uk)
Date: Tue Aug 07 2007 - 09:19:21 CEST
Message-Id: <46B82AF7.AC0B.0006.3@ccw.gov.uk> Date: Tue, 07 Aug 2007 08:19:21 +0100 From: "Gordon Ross" <G.Ross@ccw.gov.uk> Subject: Re: [suse-sles-e] Slow direct I/O performance SLES 10 SP1
>>> On 07 August 2007 at 07:10, in message <1581167128@web.de>, Andreas
Mock
<Andreas.Mock@web.de> wrote:
> thanks to the guys who made the test for me. It's interesting.
> Gordon, could you make the test with a much bigger block count?
> Isn't it really strange that you get 1MB/s on one server and
> about 46.3 MB/s on the other. There must be some write buffering
> on the driver side. The 1MB/s on the second server is about
> what I get here.
HP DL385 G1:
ns@hq-hls1:~> uname -a
Linux hq-hls1 2.6.16.46-0.12-smp #1 SMP Thu May 17 14:00:09 UTC 2007
x86_64 x86_64 x86_64 GNU/Linux
ns@hq-hls1:~> dd oflag=direct if=/dev/zero of=data.out bs=64k
count=10000
10000+0 records in
10000+0 records out
655360000 bytes (655 MB) copied, 55.7774 seconds, 11.7 MB/s
HP DL385G1:
ns@hq-hls2:~> uname -a
Linux hq-hls2 2.6.16.27-0.6-default #1 Wed Dec 13 09:34:50 UTC 2006
x86_64 x86_64 x86_64 GNU/Linux
ns@hq-hls2:~> dd oflag=direct if=/dev/zero of=data.out bs=64k
count=10000
10000+0 records in
10000+0 records out
655360000 bytes (655 MB) copied, 54.9715 seconds, 11.9 MB/s
HP DL385G2:
ns@hq-hls3:~> uname -a
Linux hq-hls3 2.6.16.46-0.12-smp #1 SMP Thu May 17 14:00:09 UTC 2007
x86_64 x86_64 x86_64 GNU/Linux
ns@hq-hls3:~> dd oflag=direct if=/dev/zero of=data.out bs=64k
count=10000
10000+0 records in
10000+0 records out
655360000 bytes (655 MB) copied, 6.40011 seconds, 102 MB/s
VMWare ESX on DL385 (with EMC Clariion disc storage)
ns@ns-web:~> uname -a
Linux ns-web 2.6.16.21-0.8-default #1 Mon Jul 3 18:25:39 UTC 2006 i686
athlon i386 GNU/Linux
ns@ns-web:~> dd oflag=direct if=/dev/zero of=data.out bs=64k
count=10000
10000+0 records in
10000+0 records out
655360000 bytes (655 MB) copied, 23.4961 seconds, 27.9 MB/s
GTG
-- — Gordon Ross, Network Manager/Rheolwr Rhydwaith Countryside Council for Wales/Cyngor Cefn Gwlad Cymru --------------------------------------------------------------------- To unsubscribe, e-mail: suse-sles-e-unsubscribe@suse.com For additional commands, e-mail: suse-sles-e-help@suse.com
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