From: Stefan Priebe <s.priebe@profihost.ag>
To: Mark Nelson <mark.nelson@inktank.com>
Cc: Sage Weil <sage@inktank.com>,
"ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>
Subject: Re: speedup ceph / scaling / find the bottleneck
Date: Sun, 01 Jul 2012 23:27:30 +0200 [thread overview]
Message-ID: <4FF0C0C2.2010407@profihost.ag> (raw)
In-Reply-To: <4FF0BD84.1050607@inktank.com>
Am 01.07.2012 23:13, schrieb Mark Nelson:
> On 7/1/12 4:01 PM, Stefan Priebe wrote:
>> Hello list,
>> Hello sage,
>>
>> i've made some further tests.
>>
>> Sequential 4k writes over 200GB: 300% CPU usage of kvm process 34712 iops
>>
>> Random 4k writes over 200GB: 170% CPU usage of kvm process 5500 iops
>>
>> When i make random 4k writes over 100MB: 450% CPU usage of kvm process
>> and !! 25059 iops !!
>>
> When you say 100MB vs 200GB, do you mean the total amount of data that
> is written for the test?
Yes/No, it is the max amount of data written but for random I/O it is
also the range like random block device position between 0 and X where
to write the 4K block.
> Also, are these starting out on a fresh
> filesystem?
Yes, 5 Min old in this case ;-)
Stefan
next prev parent reply other threads:[~2012-07-01 21:27 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-29 10:46 speedup ceph / scaling / find the bottleneck Stefan Priebe - Profihost AG
2012-06-29 11:32 ` Alexandre DERUMIER
2012-06-29 11:49 ` Mark Nelson
2012-06-29 13:02 ` Stefan Priebe - Profihost AG
2012-06-29 13:11 ` Stefan Priebe - Profihost AG
2012-06-29 13:16 ` Stefan Priebe - Profihost AG
2012-06-29 13:22 ` Stefan Priebe - Profihost AG
2012-06-29 15:28 ` Sage Weil
2012-06-29 21:18 ` Stefan Priebe
2012-07-01 21:01 ` Stefan Priebe
2012-07-01 21:13 ` Mark Nelson
2012-07-01 21:27 ` Stefan Priebe [this message]
2012-07-02 5:02 ` Alexandre DERUMIER
2012-07-02 6:12 ` Stefan Priebe - Profihost AG
2012-07-02 16:51 ` Gregory Farnum
2012-07-02 19:22 ` Stefan Priebe
2012-07-02 20:30 ` Josh Durgin
2012-07-03 4:42 ` Alexandre DERUMIER
2012-07-03 4:42 ` Alexandre DERUMIER
2012-07-03 7:49 ` Stefan Priebe - Profihost AG
2012-07-03 15:31 ` Sage Weil
2012-07-03 18:20 ` Stefan Priebe
2012-07-05 21:33 ` Gregory Farnum
2012-07-06 3:50 ` Alexandre DERUMIER
2012-07-06 8:54 ` Stefan Priebe
2012-07-06 17:11 ` Gregory Farnum
2012-07-06 18:09 ` Stefan Priebe - Profihost AG
2012-07-06 18:17 ` Gregory Farnum
2012-07-09 18:21 ` Stefan Priebe
2012-07-03 19:16 ` Stefan Priebe
2012-07-02 13:19 ` Stefan Priebe - Profihost AG
2012-06-29 12:33 ` Stefan Priebe - Profihost AG
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