From: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
To: Mark Nelson <mark.nelson@inktank.com>
Cc: Gregory Farnum <greg@inktank.com>,
"ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>
Subject: Re: OSD Hardware questions
Date: Thu, 28 Jun 2012 15:21:18 +0200 [thread overview]
Message-ID: <4FEC5A4E.1090209@profihost.ag> (raw)
In-Reply-To: <4FEB2E07.6010402@inktank.com>
Am 27.06.2012 18:00, schrieb Mark Nelson:
> On 06/27/2012 10:28 AM, Stefan Priebe wrote:
>>> Well, as we said, 1GHz/OSD was a WAG (wild-ass guess), but 3.6GHz+/OSD
>>> is farther outside of that range than I would have expected. It might
>>> just be a consequence of using SSDs, since they can sustain so much more
>>> throughput.
>>
>> Sure it was just so much away from 1Ghz that i wanted to ask.
>>
>>> What is the cluster doing when you see those CPU usage numbers?
>> random write I/O from one KVM. 14k I/Ops with random 4k writes.
>>
>> Stefan
>
> I think I was seeing about 80-85% CPU utilization with 5 SSD OSDs on our
> 6-core AMD nodes, but I was just doing sequential writes with rados bench.
While doing sequential writes i see pretty low CPU usage. Random writes
is the problem.
Stefan
next prev parent reply other threads:[~2012-06-28 13:21 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-27 13:04 OSD Hardware questions Stefan Priebe - Profihost AG
2012-06-27 13:55 ` Mark Nelson
2012-06-27 14:55 ` Jim Schutt
2012-06-27 15:19 ` Stefan Priebe
2012-06-27 17:23 ` Jim Schutt
2012-06-27 17:54 ` Stefan Priebe
2012-06-27 18:38 ` Jim Schutt
2012-06-27 18:48 ` Stefan Priebe
2012-06-27 19:10 ` Jim Schutt
2012-06-27 19:14 ` Jim Schutt
2012-06-27 15:53 ` Mark Nelson
2012-06-27 17:59 ` Jim Schutt
2012-06-27 15:13 ` Stefan Priebe
[not found] ` <CAPYLRzj916kW=KLy3dMTVPJRoNtPMP_Ejz+YAxRUJ5jZc+HeMg@mail.gmail.com>
2012-06-27 15:28 ` Stefan Priebe
2012-06-27 16:00 ` Mark Nelson
2012-06-28 13:21 ` Stefan Priebe - Profihost AG [this message]
2012-06-28 14:38 ` Mark Nelson
2012-06-28 15:18 ` Alexandre DERUMIER
2012-06-28 15:33 ` Sage Weil
2012-06-28 15:45 ` Alexandre DERUMIER
2012-06-28 15:48 ` Jim Schutt
2012-06-28 21:25 ` Stefan Priebe
2012-06-29 11:37 ` Mark Nelson
2012-06-29 12:35 ` Stefan Priebe - Profihost AG
2012-06-28 16:01 ` Stefan Priebe
2012-06-28 16:00 ` Stefan Priebe
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