Re: [Qemu-devel] Lock contention in QEMU

[Weiwei Jia]

On Thu, Dec 15, 2016 at 3:06 AM, Stefan Hajnoczi <address@hidden> wrote:
> On Thu, Dec 15, 2016 at 12:17:09AM -0500, Weiwei Jia wrote:
>> BTW, do we have an example to show users how to config following
>> virtio-blk dataplane commands into XML configuration file?
>>
>> qemu -object iothread,id=iothread0 \
>>       -drive if=none,id=drive0,file=test.img,format=raw,cache=none \
>>       -device virtio-blk-pci,iothread=iothread0,drive=drive0
>
> https://libvirt.org/formatdomain.html#elementsIOThreadsAllocation
>
> See also <cputune><iothreadpin> and <driver iothread=>.

It seems that the libvirt XML configuration in above link [1] is
different from the configuration which you said in your blog [2]. Your
blog just said how to use x-data-plane for virtio-blk but libvirt XML
configuration doesn't say anything about x-data-plane. Does it in
default support by latest QEMU version. If I want to test virtio-blk
or virtio-scsi data-plane to make timeslice more stable, what version
of QEMU/KVM should I use? Would you please give me some suggestions?
Thank you.

[1] https://libvirt.org/formatdomain.html#elementsIOThreadsAllocation
[2] http://blog.vmsplice.net/2013/03/new-in-qemu-14-high-performance-virtio.html

Cheers,
Weiwei Jia