[mythtv-users] Performance problem

Raphael Pooser rpooser at gmail.com
Mon May 15 17:33:18 EDT 2006

Jonathan Rogers wrote:
> Raphael Pooser wrote:
>> Jonathan Rogers wrote:
>>> Raphael Pooser wrote:
>>>> I would put the problem at none of the above, and move it on to your 
>>>> graphics card.
>>>> At least when I first installed the drivers for my ATI card, it wasn't 
>>>> even using XV, causing it to eat up 60% of the processor just to watch a 
>>>> 640x480 stream, and with a software encoder taking about 40% to capture 
>>>> it, I was getting pauses exactly like the ones you're getting.  After 
>>>> making sure I had XV working, I got around 5% to watch a stream by 
>>>> itself, and closer to 50% to watch something live or watch and record at 
>>>> the same time.
>>>> So I would give your graphics card driver a look.  Are you using fglrx?  
>>>> If so, make sure your vendor string for OGL reads ATI and not mesa, or 
>>>> XV won't be working either.
>>>> I've heard that XV works perfectly when using "ati" in X, but I don't 
>>>> think "ati" supports the xpress 200, not 100% sure.
>>>> Also, "ati" won't let you use TV out.
>>> Xvideo and OpenGL are separate features, so checking the OpenGL status
>>> doesn't really help for video. If you want to check if Xv is working,
>>> simply run the "xvinfo" utility. If Xv is working, it'll show details of
>>> the video overlay; if not, it'll say there is no overlay.
>>> Jonathan Rogers
>> Of course they're not related, but with fglrx if you don't have ATI 
>> openGL binaries working then the driver isn't properly installed and xv 
>> will not work either.  This is true if you're using fglrx.  So an easy 
>> way to check if the module is properly installed and getting loaded is 
>> to check the vendor string for OGL.  Are you using an ATI card with 
>> fglrx by any chance?
>> Raphael
> I have a Radeon 8500 in my box. I'm currently using X.org's radeon
> driver, but I've used fglrx in the past. I do know that OpenGL can be
> broken while Xvideo is working, since the former is complex system
> involving X driver, kernel driver, and userspace library, while Xvideo
> configuration generally only depends on the X driver.
> Jonathan Rogers
Hmm good to know, although that wasn't my experience.  I've had fglrx 
"working" with TV out and a good display and all, but couldn't get XV up 
and running for the life of me.  Various howto's typically stated the 
general rule of thumb was that if your OGL was mesa, then the kernel 
module wasn't working even when the X driver was.  I agree that the 
kernel module shouldn't matter for xv, but in the two cases I've 
installed ATI cards using fglrx, I could only get xv working once the 
kernel module was working... just stating from personal experience 
there.  However, those were both 9600 variants, 9600pro and vanilla, so 
it's possible there are some differences there - can't know for sure 
since fglrx is a foobarred proprietary driver ;)

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