[mythtv] performance

Kevin Bowen mythtv-dev@snowman.net
Tue, 17 Dec 2002 17:11:41 -0800


Hello all,
I've been browsing through the searchable list database and seeing
discussions about some people with apparently similar hardware setups
getting vastly different myth performance, specifically some people with
athlon XP 1800+ systems seeing 50-60% cpu for live tv with mpeg4 640x480,
others at 95+%. In the time since the original thread on this topic, has
anyone made any progress on figuring out this issue? I'm curious because I
am in the latter category and want to see what I can do to get out of it.
There was talk of DMA issues... my drives both show DMA enabled, but I saw a
reference to an earlier thread about some cases of people having the
incorrect DMA driver installed, resulting in poor disk performace despite
the drives showing DMA enabled. Unfortunately I've been unable to locate the
original thread in which this issue was discussed... can anyone point me to
more info?

Also I've heard mention of SBlive being a bad card to use due to various
complexities... I have an SBlive, and yes, its a complex card to get set up
and working, but I believe I have it all ironed out now... although I'm now
wondering if it could be contributing to my poor performance... has there
been any evidence anyone is aware of that would suggest the Live could be
contributing to poor performance? or was it just the complexity of its setup
people were complaining about? Assuming there's no definitive answer to
this, (warning: linux newbie question) in order to investigate myself, is
there an easy way to monitor the cpu time being used by my sound driver?

Lastly, could system ram be contributing? I have non-DDR ram (only 128mb)...
any idea if this could be a factor?

thanks in advance for any ideas anyone might have,

Kevin Bowen