[mythtv-users] Problems with multiple pvr cards

[Brian L. Walter]

Russ W. Knize wrote:
> 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
>>     
Dave,

Misery loves company:)  At least some one else is seeing the same type 
of issue.

I guess one thing I'm going to have to do is call Asus, as I can't find 
a way to modify the latency on my motherboard.  I use setpci, but, the 
value doesn't 'take'.  And when I emailed them, I got a 'This is too 
hard to respond to in mail, call us'' response...*sigh*.

I hadn't realized 0.10.2 was in svn.  The last time I tried, I believed 
it was still 0.10.1.

When you modified the the encoder buffer size, was that in the driver, 
or in myth?

TIA
Brian