[FFmpeg-devel] VP8 sliced threading

Reimar Döffinger Reimar.Doeffinger at gmx.de
Sat Jul 21 11:56:02 CEST 2012


On Wed, Jul 18, 2012 at 03:59:12PM +0200, Michael Niedermayer wrote:
> On Wed, Jul 18, 2012 at 12:26:48AM +0200, Michael Niedermayer wrote:
> > On Tue, Jul 17, 2012 at 05:27:53PM +0200, Reimar Döffinger wrote:
> > > On Tue, Jul 17, 2012 at 04:42:11PM +0200, Michael Niedermayer wrote:
> > > > On Mon, Jul 16, 2012 at 09:47:16AM +0200, Reimar Döffinger wrote:
> > > > > On 16 Jul 2012, at 02:01, Michael Niedermayer <michaelni at gmx.at> wrote:
> > > > > > On Wed, Jul 11, 2012 at 11:26:14PM -0400, Daniel Kang wrote:
> > > > > >> My implementation no longer uses sched_yield().
> > > > > > 
> > > > > > patches applied by luca and merged by me
> > > > > 
> > > > > And thus we accumulate more buggy threading code that will randomly fail and make helgrind cry.
> > > > > Please someone at least mark the synchronization variables used outside a locked area as volatile.
> > > > 
> > > > i posted 2 patches that i hope should address this issue
> > > 
> > > Thank you, I think they are good. Did you try to benchmark a bit to
> > > ensure it has no unexpected bad effects? Even if it's a bug fix IMHO
> > > I think it's a good idea to know if it changes anything.
> > 
> > didnt had time to benchmark yet
> 
> i couldnt see a speed difference for the pthread/h264 changes
> the vp8 changes seem to cause a slowdown of around 0.5%

Seems reasonable/as expected to me IMHO.


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