[mythtv] performance

[Isaac Richards]

On Friday 13 December 2002 07:28 pm, Ray wrote:
> It's really sort of odd, some people with similar systems seem to be
> performing MUCH better but there are number of people with performance much
> like yours.  For some of these people it turns out to be that dma either is
> not enabled or is not being fully taken advantage of (no 80 wire cable,
> wrong ide driver in kernel etc) but there also seem to be a number of
> "mystry systems" on this list that just arn't performing as well as they
> should.  Hopefully one of the people with problems will start collecting as
> much info as they can from everyone who is having problems (after
> eliminating the DMA issue) and start looking for patterns.  It would also
> help to collect data on the cpu usage during JUST record and JUST playback
> and compare with similar systems that seem to be working correctly.  It
> could be a particular sound card/sound driver, video card/driver,
> motherboard chipset etc is basically hogging the machine while it waits for
> some event to happen.  It also could be that with some distros Myth (or
> really avilib) isn't using whatever optomizations are available for a
> particular cpu.  I know on my system it seems that just about every
> player/encoder needs it's own different version of avilib for example.

I kinda think the issue might be RAM speed..  The big drop in CPU usage from 
the direct rendering stuff was because copying large chunks of ram around 30 
times a second is rather expensive, and the direct rendering stuff got rid of 
a couple of those copies.  Dunno, though =)

Isaac

Isaac