[asterisk-users] PRI debugging ...

[Tony Mountifield]

In article <4831A09A.6060807 at digium.com>,
Matthew Fredrickson <creslin at digium.com> wrote:
> 
> You might try turning off echo cancellation to see if your D-channel 
> performance improves.  That would be a good test to tell if you should 
> look into perhaps getting either a faster CPU or a hardware echo 
> canceller.  It's possible that you may be saturating your poor 1.3 Ghz 
> CPU by doing echo cancellation for too many channels on it.

Yes, I tripped over this one a while ago. I couldn't understand why my
533MHz Celeron test system with a TE405P would start producing loads
of D-channel errors as soon as I got to about 6 or 7 calls through it.
Eventually I discovered echo cancellation was turned on, causing the
1ms interrupt service routines to take more than 1ms to execute!

It's much happier with no echo cancellation, although I haven't tried
running all 120 channels at once!

Cheers
Tony
-- 
Tony Mountifield
Work: tony at softins.co.uk - http://www.softins.co.uk
Play: tony at mountifield.org - http://tony.mountifield.org