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From: Markus Suvanto <markus.suvanto@gmail.com>
To: diegocg@gmail.com
Cc: linux-btrfs@vger.kernel.org
Subject: Poor performance with qemu
Date: Mon, 29 Mar 2010 22:21:20 +0300	[thread overview]
Message-ID: <bcf98daa1003291221h9ab2e05xe877ffc083e45266@mail.gmail.com> (raw)

>Hi, I'm using KVM, and the virtual disk (a 20 GB file using the "raw"
>qemu format according to virt-manager and, of course, placed on a btrfs
>filesystem, running the latest mainline git) is awfully slow, no matter
>what OS is running inside the VM. The PCBSD installer says it's copying
>data at a 40-50 KB/s rate. Is someone using KVM and having better numbers
>than me? How can I help to debug this workload?

Maybe cache=writeback helps?
-drive  file=image.raw,cache=writeback

-Markus

             reply	other threads:[~2010-03-29 19:21 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-29 19:21 Markus Suvanto [this message]
  -- strict thread matches above, loose matches on Subject: below --
2010-03-28 15:18 Poor performance with qemu Diego Calleja
2010-03-30 12:56 ` Chris Mason
2010-04-08 14:58   ` Avi Kivity
2010-04-08 15:21     ` Gordan Bobic
2010-04-08 15:26     ` Chris Mason
2010-04-08 15:28       ` Avi Kivity
2010-04-08 15:32         ` Chris Mason
2010-04-08 15:34         ` Christoph Hellwig
2010-04-08 15:36           ` Avi Kivity
2010-04-08 15:39             ` Christoph Hellwig
2010-04-08 15:32       ` Christoph Hellwig

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