[Asterisk-Users] app_rxfax creating bad faxes? (StripOffsets)

[Michael Welter]

Rich Adamson wrote:

> BTW, spandsp-pre9 is the most current.
> 

Rich, spandsp-0.0.2pre10 has been on Steve Underwood's site for some 
time.  There are also "test" app_rxfax and app_txfax modules available.

I have two Canon fax machines that consistently fail on the third page. 
  From the traces, I get a page full of "slow carrier up, slow carrier 
down" message pairs and then a T4 timeout.  I get the exact result from 
both machines.  This is on a TDM22B card.  I've tried the machine 
directly connected to the FXS module as well as dialed-up on the FXO module.

I know you've read this before (I'm trying to get Digium's attention): 
on all my machines I have CPU spiking.  The time between spikes varys, 
depending on the motherboard, from four to ten seconds.  The spike 
consumes about 30% of the CPU in "system" mode (not user) for one or two 
seconds.  You can try it on your machine by watching 'vmstat 1'. During 
the spike, the number of interrupts does not increase, meaning a 
particular interrupt is being held for 20-30ms.  When I 'modprobe -r 
wcfxs' the spikes stop and the system goes to 100% idle.

I demonstrated this to Matt O. at Digium, and he confirmed that his 
(Digium) machine was spiking.

Rich, thank you for your "clarification" post this morning--a very good 
summary.

Mike