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MythTV 0.23 running on Lucid

Bella, my mythbox has been overheating for the past few months when the furnace has been running. Whenever we would watch HD content, decoding (and likely resizing) the stream to our screen would take too much CPU horsepower. Watching an HD stream would use nearly 100% of one of the two 2.1GHz Athlon cores. Then her over-sized, quiet fan would kick into high gear. Sometimes I would feel sorry for her and pull the top cover off to let out all that hot air. VDPAU has been around for a while now, and Bella's video card is supported, so I have been itching to upgrade her to Lucid. I started a couple of weeks ago by installing to an external USB drive. This way, I didn't interrupt the regular programming. I could boot to the drive, tinker, fix, test, etc., and then boot back to the main drive when I was done.

I tried to copy over the original database so I didn't lose any settings, but that didn't seem to work very well. The database upgrade scripts kept dying on me. I finally rolled up my sleeves and dug in a little deeper. The error messages that it was giving me were about duplicate columns in tables. I am not sure how they got there, but with my mysql hacker-foo skills, I manually altered the tables to drop the columns, which allowed the script to successfully update the mythconverg database. Then it seemed to be working. Kind of.

Bella has a little USB card reader that does a variety of memory card types. For whatever reason, when probed, it reports that it has devices there already, even though there are no cards plugged in. It reports /dev/sd{d,e,f,g}. For whatever reason, mythfrontend likes to probe devices and try to mount them??? When it runs into these non-devices, it segfaults. I finally just decided to unplug the card reader from the motherboard and mythfrontend starts up just fine.

With Myth finally up and running, it doesn't take long to make sure all the settings are good. I kick off a show and notice that the processor is still running at full speed. A little more digging and I find the VDPAU setting screen. I turn it on and viola! CPU usage drops to 40%. I was a little underwhelmed by this number, hoping to see something more on the order of 5%. I don't know if it is because of the stream type or maybe my hardware? The video card is several years old and one of the earlier ones that does support VDPAU. And the stream is whatever the broadcasters in my area are using. I assume it is MPEG2, while H.264 is what VDPAU would prefer? Anyway, something is better than nothing. I just hope that the reduction in CPU thermal requirements is sufficient.