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From: Jonghwan Choi <jhbird.choi@samsung.com>
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Subject: [Qemu-devel] I/O performance degradation with Virtio-Blk-Data-Plane
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Cc: qemu-devel@nongnu.org

Hello All.

Nowdays i measured io performance with Virtio-Blk-Data-Plane.
There was something strange in test.
When vcpu count is 1, io performance is increased in test
But vcpu count is over 2, io performance is decreased in test.

i used 3.10.9 stable kernel, qemu(1.4.2) & fio 2.1

What should i check in my test?

Thanks.