[linux-dvb] Re: artefacts in picture - where can I find the moduleoptions? 2nd try

[Jon Burgess <mplayer@jburgess.uklinux.net>]

Rene Bartsch wrote:

> > I'm having artefacts in the picture (VDR). The HDD (SATA) performs with
> > 58 MB/s, so I assume it's related to the PCI-bus (on an i865PE board).
> >    
My setup has an i865G running with 4 x Nova-T PCI cards and I don't see 
any problems so I suspect the PCI bus is not the cause.

Does "femon" report any frontend errors when you see the artefacts? You 
should be able to have femon running at the same time as VDR.

Could you run "vmstat 1" while VDR is showing problems and reports a few 
lines of the output?

I know of one problem when using a combination of  VDR + Linux-2.6 + 
ext2/3. This manifests itself in the vmstat output as a high CPU% as the 
"io wait".

Is this a combination that you use?

VDR triggers a preformance regression in the 2.6 kernel by streaming 
lots of small writes to the filesystem.
I did some benchmarks to demonstrate the problem a few months ago, but 
AFAIK it has not been fixed.

To "fix" the problem I changed my video storage drive to use JFS. The 
benchmarking I performed showed that JFS, XFS and ReiserFS v4 are not 
effected by this issue.

   Jon