From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: virtio-blk performance regression and qemu-kvm
Date: Wed, 07 Mar 2012 12:21:45 +0100
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Cc: Stefan Hajnoczi <stefanha@gmail.com>, reeted@shiftmail.org,
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To: Martin Mailand <martin@tuxadero.com>
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Il 07/03/2012 11:39, Martin Mailand ha scritto:
> The host disk can at max. 13K iops, in qemu I get at max 6,5K iops,
> that's around about 50% overhead. All the test were with 4k reads, so I
> think we are mostly latency bound.

For latency tests, running without ioeventfd could give slightly better
results (-global virtio-blk-pci.ioeventfd=off).

Paolo