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Date: Wed, 20 Jun 2012 07:58:53 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] Threaded VNC server status - time to enable by
 default ?
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To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: qemu-devel <qemu-devel@nongnu.org>

On 06/20/2012 04:15 AM, Daniel P. Berrange wrote:
> We recently had a request in Fedora to enable the VNC server thread
> support in our builds of QEMU. There have been periodic messages on
> this list that suggest the threaded VNC server has better performance
> and less latency.
>
> My view though, is that there must be some good reason why QEMU does
> not enable it by default already. Can anyone say why QEMU has not
> enabled the VNC server threads by default ?
>
> If there is no such reason, can we just kill the configure options
> --{disable,enable}-vnc-thread, and have everyone use the VNC server
> thread support forever more. I struggle to see the point in maintaining
> these two separate codepaths for the VNC server. Whichever one is
> not the default is, IMHO, destined to bitrot through lack of widespread
> testing and so we're better off getting everyone to use&  test the
> same codepath.

At the time it was introduced, QEMU still has no hard requirement on having 
pthreads as a dependency (the I/O thread was still optional).

We're past that point now so there's no harm in unconditionally enabling the VNC 
thread pool.

Regards,

Anthony Liguori

>
> Regards,
> Daniel