[mythtv-users] mythbackend crashing regularly (Ubuntu 8.10, x86_64, ATI radeonhd video)

[Mike Hicks]

Hmm, my mythbackend segfaulting issue may be going away -- I had
migrated an older MythTV installation on another machine to a newer
box which is capable of decoding HD video.  I'd been using the newer
box as a frontend for the old one for a while, but the old system just
wasn't powerful enough anymore to handle the load it was under in
encoding analog, saving HD, and serving up another stream at the same
time.

I'm suspecting that the database wasn't quite kosher in some sense
after the migration -- I had about 4 recordings which either didn't
get copied over or just weren't referenced properly in the database.
Deleting them from the program listing seemed to help.  The frontend
seemed to be fairly spastic about displaying the preview image/video,
which I figured might have been triggering too many rapid requests to
the backend for it to keep up, so I disabled that.

Also, well, I'm not sure about this idea, but here goes:  The record
volume was very high on my analog tuner and sound card at the
beginning (I'm using the pcHDTV HD-3000 in analog mode), and I wonder
if the overblown audio might have caused the audio encoder to go
sideways.  That seems unlikely though.

Another theory is that the mythfilldatabase didn't quite run properly
at first, or I had to wait for the mythfilldatabase from the
0.21-fixes builds to run once and clear out the data collected by the
Ubuntu 8.10 version.

Anyway, I've now had the backend running more than 24 hours without a
crash (while it seemed to only run 5 to 25 minutes while encoding at
the beginning of this ordeal), and that's with recording and watching
about a dozen shows.  Hopefully it won't get bad again.

On Tue, Mar 3, 2009 at 3:43 AM, Paul Gardiner <lists at glidos.net> wrote:
> Jean-Yves Avenard wrote:
>>
>> ATI video drivers are such piece of crap ; only used my video card for 3
>> days until I gave up ...
>> Was a Radeon 4350
>>
>> myth would either crash or display some wierd screen
>
> I think they've improved no end lately. There's a lot of work going into
> the radeon driver, and it's often gives much better results than
> randeonhd. So I'd suggest to the OP trying swapping to radeon. I'm not
> sure about the 4350: could be a chip that the radeon driver doesn't yet
> support, but worth a try.

Yeah, I'm not a fan of the ATI drivers.  XVideo (Xv) support was
nonexistent when I got the card (in Ubuntu 8.04), even with
proprietary fglrx driver.  I'd tried a few builds of the X.org
radeonhd driver, which seemed to give better 2-D performance for
browsing regular desktop operations, but also didn't support Xv.  I
finally got scaled video support with the fglrx driver approved for
Ubuntu 8.10.

I didn't know that the radeon driver was gaining support for these
cards, so I'll have to investigate that a bit -- Thanks.

Lots of 3-D apps will crash with the fglrx driver.  I can't have
Blender run very long before going poof, and the 3-D screensavers
would always be segfaulting.  I think Google Earth has completely
locked up my box more than once.

I also get a garbled image whenever I start mythfrontend or
mythtv-setup -- somehow a display issue, as taking a screenshot or
connecting remotely via VNC would show a perfect image.  I did figure
out that if I could blindly navigate to the Setup -> Appearance
screens and step through the configuration, it would re-initialize and
paint the screen correctly.

Oh, and the frontend always segfaults at exit, but what else is new.

-- 
[ Michael Hicks | mikemn at gmail.com ]