Mythbuntu on a Via Epia SP8000e

A few years ago I got a Via Epia SP8000e to be a MythTV box. Here are the stats on the SP8000e:

• Processor: 800 MHz VIA C3 Eden (fanless). Ubuntu reports:
  processor : 0
vendor_id : CentaurHauls
cpu family : 6
model : 9
model name : VIA Nehemiah
stepping : 8
cpu MHz : 800.222
cache size : 64 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr cx8 sep mtrr pge cmov pat mmx fxsr sse up rng rng_en ace ace_en
bogomips : 1602.28
• "Integrated VIA UniChrome AGP graphics with MPEG-4 accelerator"

I had this running with Ubuntu Edgy Eft and MythTV 0.20 (I think), but it was giving me problems occasionally and the Edgy repositories have been closed down for a while so it was impossible to upgrade packages anymore. I decided to cross my fingers and try upgrading to Mythbuntu.

I started out with the Mythbuntu 8.04 install CD. Everything seemed to install without problems, and once I figured out how to do the MythTV setup properly I got it running. However, the Via C3 Eden is not very powerful, and without XvMC enabled it runs at around 70-90% CPU utilization playing back recordings. So, I tried to enable XvMC by selecting the Via XvMC as the decoder in a new Playback Profile. It didn't work, and I got the errors/problems described in this forum post and bug listing:

Problem :: VIA XvMC / MythTV 0.21 / Upgrade to Ubuntu 8.04

http://bugs.gentoo.org/show_bug.cgi?id=228473

I tried changing the libraries referenced in /etc/X11/XvMCConfig to libchromeXvMC.so.1 and libchromeXvMCPro.so.1 and that didn't fix it.

I tried doing an upgrade to Mythbuntu 8.10, and a fresh install of Mythbuntu 8.10, and still had the same problem with XvMC.

It seemed from the posts about this problem that it appeared with kernel 2.6.24, so I dug up the ISO for Mythbuntu 7.10 (its not listed on the Mythbuntu site anymore, but if you do some creative googling for mythbuntu-7.10-i386.iso you can find it). Mythbuntu 7.10 installed just fine and XvMC worked as soon as I selected Via XvMC in the appropriate MythTV Frontend setup screen (Settings -> TV Settings -> Playback something or other I think).

However, when I did a normal install of all updates Mythbuntu installed MythTV 0.21 and XvMC stopped working. I determined that with Mythbuntu 7.10 the backports repository is enabled by default, and that is where MythTV 0.21 came from, so I reinstalled Mythbuntu 7.10 from the CD, then on the Mythbuntu desktop I updated the software sources to remove backports, and then I was able to update all packages without getting bumped up to MythTV 0.21.

So, I finally have MythTV working on my Via Epia SP8000e using Mythbuntu 7.10.

If you look at the forum posting and bug report listed above Robert reports that this problem exists with Gentoo and Slackware, and that he has been able to get MythTV 0.21 working with post 2.6.24 kernels by compiling his own kernels with the memory allocator set as SLAB instead of the default SLUB. I have not tried this yet since I need some time for the scars to heal before I wade into battle with Linux again.