[mythtv-users] CONFIG_HZ setting in Linux kernel improved video playback for me

[Scott]

Greets.

Like many MythTV Gentoo users I've built my own kernel. I have a  
fairly hefty FE/BE box (core2 6600, 1GB RAM, SATA 500GB drive, Nvidia  
7600GT) that is primarily used for HDTV recording and DVD watching.  
The problem was I was still not seeing butter-smooth video,  
especially when the camera would pan across the screen. The problem  
was noticeable on both DVDs and HDTV sources.

Reading up on the 2.6.20 kernel changes I found this i386 kernel change:

	300Hz support. It is useful to have 300Hz support
	when doing multimedia work: 250 is fine for us in
	Europe but the US frame rate is 30fps (29.99 blah for
	pedants). 300 gives us a tick divisible by both 25 and 30,
	and for interlace work 50 and 60. It's also giving similar
	performance to 250Hz.

I rebuilt my 2.6.20 kernel changing CONFIG_HZ from the default 100Hz  
to 300Hz and happily saw butter-smooth video playback for both HDTV  
and DVDs.

Chances are this is my own fault as I'm sure the Gentoo stock kernels  
are already set to 1000Hz or 512Hz like FC kernels used to be. So as  
a tip, if you're trying various tweaks to improve your video playback  
and building kernels on Gentoo, don't forget to check your CONFIG_HZ  
setting as I forgot to.

--
Scott