From: matilda matilda (matilda_at_grandel.de)
Date: Tue Apr 03 2007 - 11:07:45 CEST
Message-Id: <46123581.117B.0044.0@grandel.de> Date: Tue, 03 Apr 2007 11:07:45 +0200 From: "matilda matilda" <matilda@grandel.de> Subject: SPAM: Re: Antw: Re: [suse-sles-e] Re: catastrophic disk-performance on SLES10 with SATA drives
Hi Markus,
thank you for performing the test so quickly.
I don't know what you think about this behaviour.
In my opinion it's not o.k. But probably I'm too stupid for
that stuff. ;-)
Do you have the possibility to make the test with a storage device
NOT attached to a controller using cciss? It would be really
interesting to see if it only happens with cciss.
The 54 MB/s you get are not too bad in my opinion if it's RAID5.
On a RAID1 I would expect more if you don't have too much load
otherwise.
Best regards
Andreas Mock
>>> Markus Roeffen <markus.roeffen@iws.uni-stuttgart.de> 03.04.2007 10:51 >>>
Hello Andreas,
I've run your test (with same parameters like you, so we can compare)
and realized a similar behaviour.
So here are the results on our internal raid:
server:/frei # time dd if=/dev/zero of=data.out bs=8192 count=1310720
1310720+0 records in
1310720+0 records out
10737418240 bytes (11 GB) copied, 198,851 seconds, 54,0 MB/s
real 3m19.087s
user 0m0.632s
sys 0m23.837s
Number of pdflush processes before and after the operation: 2
Number of pdflush processes _during_ the operation: 8
According to top on another bash our CPU load increased during the
operation.
We run SLES 10 here and used the kernel 2.6.16.21-0.8 with HP PSP, but
we've updated to kernel 2.6.16.27-0.9-default recently and it seems that
we can still use most of the HP webfrontends and tools.
Best regards
Markus
matilda matilda wrote:
> Hi Markus,
>
> do you have a similar behaviour as we have when you try to write a file bigger
> than what fits into the memory? Increasing count of [pdflush]-kernel-threads and
> an increasing avarage load on the machine.
>
> Could you please try this?
>
> Are you working with the HP provided drivers or with drivers which come with SLES?
>
> What SLES version do you have?
>
> We're working with internal raid. As soon as all data fit into memory the "benchmark"
> is not worth it. :-) 551MB/s, this is a raid I would like. What do you want for it? ;-)
>
> Best regards
> Andreas Mock
>
>
>
>
-- ------------------------------- Markus Roeffen Institut für Wasserbau IWS Universität Stuttgart Pfaffenwaldring 61 70569 Stuttgart Tel: +49(0)711/685-67010 Fax: +49(0)711/685-67020 Mail: markus.roeffen@iws.uni-stuttgart.de --------------------------------------------------------------------- To unsubscribe, e-mail: suse-sles-e-unsubscribe@suse.com For additional commands, e-mail: suse-sles-e-help@suse.com --------------------------------------------------------------------- To unsubscribe, e-mail: suse-sles-e-unsubscribe@suse.com For additional commands, e-mail: suse-sles-e-help@suse.com
This archive was generated by hypermail 2.1.7 : Tue Apr 03 2007 - 13:12:07 CEST