Re: [Qemu-devel] [PATCH] smoother sdl display & mouse

[Daniel P. Berrange]

On Tue, Jul 24, 2007 at 07:50:30PM +0200, Jindrich Makovicka wrote:
> Hi,
> 
> the attached patch modifies the SDL display refresh code so the mouse
> and keyboard events are processed each 10 ms instead of 30. This causes
> much better mouse behavior due to lower latency.
> 
> By default, display is still refreshed only each 30 ms to prevent the
> increase of the cpu load, but it is possible to tune the refresh rate
> via the -sdl-decimate option.

Using a command line argument to change the refresh rate doesn't seem like 
a particularly optional solution. It think it would be better to have QEMU
automatically adapt the refresh rate. eg, it would start off refreshing SDL
at 30ms  intervals. If it sees a keyboard or mouse event, it would increase
the refresh rate to 10ms. If, say, 100ms passes without any further events,
then it could decrease it to 30ms again.

That way everyone would always get the low CPU load, unless they were
actaully interacting with the mouse/keyboard in which case it would tune
itself for interactive response.

Regards,
Dan.
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