> > Hi, > > On Mon, Oct 31, 2016 at 08:49:23PM +0100, Francois Gouget wrote: > > We run the VP8 encoder in real time mode so it uses only the minimum > > amount of time needed to encode each frame. However by default it > > only uses one thread so that for large/complex frames it may run at > > less than the source fps. Besides resulting in dropped frames this > > blocks the main server thread for most of the time. > > So this patch configures the VP8 encoder to use all the CPU's physical > > core, resulting in less wall clock time spent in encode_frame(). > > > > Signed-off-by: Francois Gouget <fgouget@xxxxxxxxxxxxxxx> > > --- > > > > I am resubmitting this patch because I think the reasons for not > > applying it last time were wrong. See: > > https://lists.freedesktop.org/archives/spice-devel/2016-March/027026.html > > > > Here is an illustration of the impact of threading for the > > big_buck_bunny_1080p_h264.mov video: > > > > http://fgouget.free.fr/tmp/Spice-vp8-threads.png > > http://fgouget.free.fr/tmp/Spice-vp8-threads.xls > > > > The graph shows the time spent in encode_frame() (taken from the > > standard traces) when vp8enc uses 1, 2 or 4 threads. > > Well, I did not say that using more threads was not useful, I was only > worried that using all CPUs could not be so good (eg multiple VMs > encoding at the same time), especially as I think you mentioned that > trying to use too many threads was causing rendering issues? > I agree with both... I think the solution is an option to enable/disable and personally I would prefer to use less thread by default. > > I'll also note that the h264 encoder automatically uses multiple > > threads already so this patch only brings vp8enc in line with it. > > After a quick look at x264, it seems to be using more threads than > physiical CPUs. Is it ok too with vp8enc? I'd really like that we don't > have that code invoking egrep as a fallback, ie no g_get_num_processors, > no _SC_NPROCESSORS_ONLN, tough luck? (the latter is available on el6). > > Christophe > I think we can assume, if system has not these options has only one core... Frediano _______________________________________________ Spice-devel mailing list Spice-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/spice-devel
