[Asterisk-Dev] IAX phones and CPU usage problem

[Claude Klimos]

Hi all,

We have an asterisk server running on redhat 9, with a TE410P card
connected to 4 PRIs, on a dual 2.6GHz xeon server with 2GB of RAM. We
also have 10-12 agents using IAX based softphones on winxp. Almost all
of the usage consists of outbound calls done automatically through the
PRIs and connected  to an agent once answered. The agents perform the
'ready' operation via IAX by calling iaxc_call() to call an extension
that in turn calls AgentLogin. The 'Not ready' operation is done
automatically once the phone call ends by invoking iaxc_dump_call().
This ready/not-ready sequence is made repeatedly, for every call
connected to an agent.

We noticed that the CPU usage of Asterisk if increasing with time. When
we start Asterisk, everything seems ok, but with time the CPU usage goes
higher and higher. After a day of work or so, the 'top' command shows
that Asterisk is consuming around 90-95% of the CPU, some times 100%,
and the voice on the softphones suffers dramatically.

When all the agents become Not Ready by doing an iaxc_dump_call(), the
CPU goes down to 1-2%. As soone as one softphone does a iaxc_call() the
CPU jumps up again. This situation is very serious to us especially
since we are planning to deploy over 50 agents on this system.

Any ideas, hints, recommendations are greatly appreciated.

Regards,

Claude