[mythtv-users] Fwd: Problem with XvMC being slow

[Jerry Rubinow]

On 1/7/06, Jerry Rubinow <jerrymr at gmail.com> wrote:
>
> On 1/6/06, Steve Adeff <adeffs at gmail.com> wrote:
> > On Friday 06 January 2006 00:05, Jerry Rubinow wrote:
> > > On 1/5/06, Jerry Rubinow < jerrymr at gmail.com> wrote:
> > > > On 1/5/06, Joseph A. Caputo <jcaputo1 at comcast.net> wrote:
> > > > > On Thursday 05 January 2006 1:21, Jerry Rubinow wrote:
> > > > > > When using XvMC to play back video, CPU usage is low (30% for HD,
> 10%
> > > > > > for SD), but the video plays back slower than realtime.  I'm using
> an
> > > > > > Nvidia 5200 card, with driver version 7667 (although I've tried
> every
> > > > > > version up to the current 8XXX).
> > > > > >
> > > > > >  Is there anything I should check?  Anything obviously wrong from
> the
> > > > > > following details?  Or is this the XvMC slowdown I've read about?
> > > > > > What are my options for fixing this?
> > > > >
> > > > > I could be way off base on this, but something in my memory is
> nagging
> > > > > me... something about maybe Nvidia's XvMC not supporting/performing
> > > > > well at certain resolutions?  Have you tried changing your
> horizontal
> > > > > resolution to something smaller, like 1024?
> > > >
> > > > No, but that's a good suggestion - I'll try it tonight.  Thanks.
> > >
> > > No luck.  I tried setting both X and the GUI setup in myth to 800x600
> > > and it's still slow playing HD.  Not stuttering, just slower than real
> > > time.  I didn't mention before, but I'm using pretty much a straight
> > > following of Jarod's guide with FC4, 2.6.14, on a P4 2.8.
> > >
> > > I'm so close to having beautiful HD playback, can anybody suggest things
> to
> > > try?
> >
> > poney up for a faster processor? I know its prbly not an optioin, but with
> a
> > 3.0 or 3.2GHz cpu you'll be able to play back HD without XvMC.
> > Does OpenGL sync work with XvMC? I dunno, but might be worth a try. Also,
> try
> > disabling any deinterlacing? Oh, what about audio buffering options, have
> you
> > played with those?
> > Also, don't forget you have to restart mythfrontend everytime you make one
> of
> > these changes. minor bug...
>
>
> I'm already at the fastest processor a Pundit will accept, so I'd have to
> scrap my whole nice form factor frontend to do that.  I'm using OpenGL sync,
> and deinterlacing is already disabled.  I haven't played with audio options
> at all, but I don't think that can be it, since if I turn off XvMC, NTSC
> plays back fine, but with it on, it plays back slow (not stuttering, just
> slow-mo).
> I'm out of town this weekend, but when I get back, I'm going to try
> compiling mplayer with xvmc support and see if that has problems playing
> back too.  That will at least either eliminate myth from the equation or
> point to myth as the culprit.

For anybody following this thread, increasing the ringbuffer size was
what finally fixed this problem.

-Jerry