[mythtv-users] Problems with multiple pvr cards

[Russ W. Knize]

I've been having many issues with DMAs lately.  I changed a lot of
things at once and have rolled back the hardware and I still get them.
Part of the issue is with ivtv.  There is a bug in 0.10.1 where the
interrupt handler does some slow PIO to retrieve VBI data.  This ties-up
the system preventing it from handling other DMAs.  With a PVR-500, two
NICs, a RAID-5 SATA card, and a PATA card, I was getting DMA errors with
just one encoder going.  If both encoders go, the system is brought to
it's knees and will either die or the encoder hardware will lockup.  

Turning off VBI capture in Myth does not seem to stop ivtv from reading
the data.  I modified the driver to turn off this feature which helped,
but was not a total solution.  Tuning the PCI latency settings and
increasing the encoder buffer sizes also helped, but I still get
occasional issues.

Next I am going to try the 0.10.2 SVN branch.  Downgrading is
problematic, as I will have to downgrade my kernel as well.

Good luck,
Russ

On Wed, 2007-05-09 at 17:14 -0700, David Rees wrote:
> On 5/8/07, Brian L. Walter <blwalter at gmail.com> wrote:
> > However, when Myth goes to record on all 3, I start getting ENC DMA
> > Errors, anywhere from  immediately to 20-30 minutes.
> >
> > I've read that there is an interrupt issue with the 0.10.1, and was
> > wondering if this is a result of that issue.
> 
> FWIW, the latest code in the ivtv 0.10 branch appears to be more
> stable for me than 0.10.1. Not quite sure why, but you may want to
> give it a shot.
> 
> -Dave
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users