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Subject: Re: [Qemu-devel] virtio-scsi vs. virtio-blk
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel <qemu-devel@nongnu.org>, ronnie sahlberg <ronniesahlberg@gmail.com>


Am 09.08.2012 15:42, schrieb Paolo Bonzini:
> Il 09/08/2012 15:39, Stefan Priebe - Profihost AG ha scritto:
>>> scsi-generic would indeed incur some overhead because it does not do
>>> scatter/gather I/O directly, but scsi-hd/scsi-block do not have this
>>> overhead.  In any case, that should be visible through the output of
>>> perf if it is significant.
>>
>> Thanks for your help and replies. I'm a little bit lost on all these
>> comments. So what to check / do next?
>
> Try with the deadline scheduler, and run "perf top" in guest/host if the
> problems persist.

Thanks will do so. Right now i'm getting virtio_net virtio2: output:id 1 
is not a head!

and then network is down.

Stefan