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From: Stefan Priebe <s.priebe@profihost.ag>
To: "ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>
Subject: less cores more iops / speed
Date: Wed, 07 Nov 2012 23:02:18 +0100	[thread overview]
Message-ID: <509ADA6A.9000807@profihost.ag> (raw)

Hello again,

I've noticed something really interesting.

I get 5000 iops / VM for rand. 4k writes while assigning 4 cores on a 
2.5 Ghz Xeon.

When i move this VM to another kvm host with 3.6Ghz i get 8000 iops 
(still 8 cores) when i then LOWER the assigned cores from 8 to 4 i get 
14.500 iops. If i assign only 2 cores i get 16.000 iops...

Why does less kvm cores mean more speed?

Greets,
Stefan

             reply	other threads:[~2012-11-07 22:02 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-07 22:02 Stefan Priebe [this message]
2012-11-08  0:00 ` less cores more iops / speed Joao Eduardo Luis
2012-11-08  0:16   ` Openstack - Boot From New Volume Quenten Grasso
2012-11-08  0:59   ` less cores more iops / speed Mark Nelson
2012-11-08  8:45     ` Stefan Priebe - Profihost AG
2012-11-08  8:58       ` Alexandre DERUMIER
2012-11-08  9:02         ` Stefan Priebe - Profihost AG
2012-11-08  9:05           ` Alexandre DERUMIER
2012-11-08  9:28             ` Stefan Priebe - Profihost AG
2012-11-08 13:19       ` Mark Nelson
2012-11-08 15:14         ` Stefan Priebe - Profihost AG
2012-11-08 15:53           ` Alexandre DERUMIER
2012-11-08 21:52             ` Andrey Korolyov
2012-11-09  8:43             ` Stefan Priebe - Profihost AG
2012-11-08  0:59   ` Mark Nelson
2012-11-08  5:42 ` Dietmar Maurer
2012-11-08  5:49   ` Dietmar Maurer
2012-11-08  6:20     ` Stefan Priebe - Profihost AG
2012-11-08  5:49   ` Stefan Priebe - Profihost AG
2012-11-08  5:54     ` Dietmar Maurer
2012-11-08  6:21       ` Stefan Priebe - Profihost AG
  -- strict thread matches above, loose matches on Subject: below --
2012-11-12 15:33 [pve-devel] " Stefan Priebe - Profihost AG
     [not found] ` <50A116DC.2020509-2Lf/h1ldwEHR5kwTpVNS9A@public.gmane.org>
2012-11-12 15:39   ` Alexandre DERUMIER

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