[mythtv-users] Jitter Test?

[Wood, Mike]

Gang,

I read this in a post from several months ago:

"Just out of curiosity, try running top and increase the speed (hit s, set 
to .3) Then run hdparm -t /dev/hd?. Does it spike (System) pretty 
heinously? Mine benches just as well as yours does, but it seems that my 
chipset (AMD 760) has some crummy IDE drivers...the CPU spikes in the 60's 
just when doing hdparm. So I'm thinking my issue is now the onboard 
controller not being up to the task of writing that much data to the disc 
without chopping out the CPU in the process. "

Has anybody else done this and seen these results?  I just did this on my
Myth Box and the hdparm test consumed, at peak, about 40% of the CPU all by
itself.  So now I'm wondering if this is why I have occasional jitter during
LiveTV.  When I'm watching livetv, I'm using usually between 30%-40% of the
cpu, sometimes more, sometimes less.  So if both spike at the same time, I
could be running out of CPU...I think?

I'm trying to find out what chipset I have in this box.  I don't even know
yet, it was a hand-me down box and I never bothered to look.  Depending on
that answer, what can be done to improve this performance?  I already have
DMA enabled, 32 bit enabled, write-cache enabled.  Can something be done for
the IDE driver itself if that's a problem?  I've never mucked with that,
never needed to.

Any ideas/help appreciated,
Mike