[mythtv-users] High-Definition Playback performance data

[Brad Templeton]

On Tue, Apr 19, 2005 at 05:21:32PM -0500, Paul Leppert wrote:
> On 4/3/05, Brad Templeton <brad+myth at templetons.com> wrote:
> <snip>
> > They include:
> > 
> >     a) Right drivers for card with your kernel
> >     b) Proper AGP bus speed and AGP interface driver in use
> >     c) Proper user of openGL sync for retrace
> >     d) Proper settings for deinterlace and, if used, xvmc
> >     e) Proper sound settings and handling of 5.1 sound and multiple streams
> >     f) Real time scheduling of playback thread
> >     g) Making sure disk or network speed is adequate
> >     h) Nothing else sucking up CPU on the machine
> > 
> > And of course having the right cards and memory itself.
> 
> Brad,  I think this is great.  Even better would be how one goes about
> checking each of these items.  As a relative newbie, I'm not sure how
> to *confirm* your list items a, b, e, f, and g.  I'll take a shot at
> the others:
> 
> a) Right drivers for card with your kernel
> 
> Don't know how to confirm which one is loaded...

A few different things to look at.   One is /var/log/<xservername>.0.log
which will show all the things that happened when your X server stated up.

If you run nvidia, go into /proc/driver/nvidia for all sorts of useful
stuff, including (b) below.
> 
> b) Proper AGP bus speed and AGP interface driver in use
> 
> 
> e) Proper sound settings and handling of 5.1 sound and multiple streams
> 
> Not sure...  I am using ALSA:spdif for sound and I can confirm that it
> works since my DD receiver switches to digital mode.  Not sure what
> exactly to check here.

Well, first thing to make sure you really have alsa and are using it.
I'm not much of an expert on alsa conf.
> 
> f) Real time scheduling of playback thread
> 
> Don't know...  Even after using chmod a+s on mythfrontend, my logs
> still say that running as SUID would help, so don't know if I'm doing
> this correctly or not (or even if that message is relevant).

Yes, new versions of linux that include selinux refuse to allow this so
this is advice for people with distros that don't do that.