[Asterisk-Users] Re: Problems with TDM400P card

[Mike Mueller]

On Thu, May 05, 2005 at 12:11:51PM -0400, Andrew Kohlsmith wrote:
> On May 5, 2005 11:13 am, Mike Mueller wrote:
> 
> > What was that? No buffering? That means its tx/rx ISR should have priority
> > over those servicing interfaces with buffering.  Is that happening?
> 
> It's one of the primary reasons these cards are *so* interrupt and system 
> sensitive.
> 
> But remember; system didn't change, drivers did.  the problem was not there 
> with earlier drivers and is now.   Therefore, since everything else has 
> remained constant, the problem is with the drivers.

Sounds like the problem is isolated.  So you have a
system that works with the old driver revision and doesn't work with the new
driver revision?  Can you identify a working revision and an early
broken revision so we can do a diff and code review?
> 
> > Assuming there are a lot of samples from TDM missing - and that
> > lack of buffering makes that plausible - this could be measured in a
> > working system by dumping TDM input into a file over a 10 minute period
> > as measured by gettimeofday and determining the amount of shrinkage that
> > occurred.  Using a long time period like 10m will reduce the effects of
> > Linux scheduler latency and it will ensure capture of the 5-second-100%-CPU
> > effect.
> 
> Well I think we're missing frames because the driver is holding the system 
> hostage for such a long amount of time every so often.  Steve's proposed a 
> couple of tests for measuring this, we just need to get off our duffs and do 
> it.  :-)

Do you need to?  Seems like code review time.  I'll contribute a pair of
eyes B-).

-- 
Mike