From: Kevin Wolf <kwolf@redhat.com>
To: Alexandre DERUMIER <aderumier@odiso.com>
Cc: Dietmar Maurer <dietmar@proxmox.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] qcow2: slow internal snapshot creation
Date: Fri, 23 Nov 2012 15:58:09 +0100 [thread overview]
Message-ID: <50AF8F01.9060008@redhat.com> (raw)
In-Reply-To: <9574d6cc-30fe-4424-b7e7-d363e2abdba9@mailpro>
Am 23.11.2012 15:17, schrieb Alexandre DERUMIER:
>>> Preallocation doesn't matter much these days.
>
> I have done benchmark through nfs on a netapp san, (with directio),
>
> I got 300 iops without preallocation, and 6000 iops with preallocation ....
This doesn't sound right, even for writethrough modes.
Can you post more details about your benchmark setup so that this can be
reproduced? And does it reproduce with local files as well or only using
NFS?
Kevin
next prev parent reply other threads:[~2012-11-23 14:58 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-23 7:26 [Qemu-devel] qcow2: slow internal snapshot creation Dietmar Maurer
2012-11-23 14:03 ` Alexandre DERUMIER
2012-11-23 14:09 ` Kevin Wolf
2012-11-23 14:17 ` Alexandre DERUMIER
2012-11-23 14:58 ` Kevin Wolf [this message]
2012-11-23 15:53 ` Alexandre DERUMIER
2012-11-23 15:31 ` Kevin Wolf
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