Implement THREAD_PRIORITY_TIME_CRITICAL

Con Kolivas kernel at kolivas.org
Tue Apr 4 18:49:12 CDT 2006


On Wednesday 05 April 2006 09:45, Robert Reif wrote:
> One problem that I am seeing is that there is no practical way to
> guarantee synchronization between the sound card hardware and the
> sound card thread.  OSS doesn't support poll/select reliably in
> all drivers and the esd driver just writes to a socket.  We try to
> synchronize to the hardware by using a one-shot timer set to the
> expected processing time calculated from the sound card data
> format.  The problem I see in the esd driver is that we set a
> timeout to poll of for example 12 ms but what we really get is
> is a 20 ms sleep.  We compensate for this by sending as much
> data as we can.  Using virtualized hardware like alsa dmix just
> removes us even further from the hardware we would like to
> synchronize to by blocking.

Apart from legacy, is there a reason you haven't moved en-masse to alsa? It is 
the only supported driver in current kernels now. Talking to oss, the oss 
compatibility module or worse through a sound driver like esd, arts, 
gstreamer, jack... etc just adds more potential for desynchronisation.

Cheers,
Con



More information about the wine-devel mailing list