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Date: Tue, 28 Feb 2012 17:05:44 +0000
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From: Stefan Hajnoczi <stefanha@gmail.com>
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Subject: Re: [Qemu-devel] virtio-blk performance regression and qemu-kvm
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To: martin@tuxadero.com
Cc: Dongsu Park <dongsu.park@profitbricks.com>, kvm@vger.kernel.org, qemu-devel@nongnu.org

On Tue, Feb 28, 2012 at 4:39 PM, Martin Mailand <martin@tuxadero.com> wrote=
:
> I could reproduce it and I bisected it down to this commit.
>
> 12d4536f7d911b6d87a766ad7300482ea663cea2 is the first bad commit
> commit 12d4536f7d911b6d87a766ad7300482ea663cea2
> Author: Anthony Liguori <aliguori@us.ibm.com>
> Date: =A0 Mon Aug 22 08:24:58 2011 -0500

This seems strange to me.

What commit 12d4536f7 did was to switch to a threading model in
*qemu.git* that is similar to what *qemu-kvm.git* has been doing all
along.

That means the qemu-kvm binaries already use the iothread model.  The
only explanation I have is that your bisect went down a qemu.git path
and you therefore tripped over this - but in practice it should not
account for a difference between qemu-kvm 0.14.1 and 1.0.

Can you please confirm that you are bisecting qemu-kvm.git and not qemu.git=
?

Stefan