[OpenSIPS-Users] MediaProxy loading issues - I think I need some tuning here

[Jock McKechnie]

Greetings all;

We have several mediaproxy systems running in small scale production
(~50-100 calls concurrently) and have been very pleased with the
results. We find that we have to restart the relay/dispatcher machines
daily to keep them ticking over (they tend to get lost on their own
after a few days runtime), but this is a minor inconvenience.

Until today. Today I tried moving one of our small carrier circuits
over to it and gee whiz did all sorts of exciting things happen. I
have our systems set up with an initial OpenSIPS/media-dispatcher
running on a VM (public IP). This dispatcher speaks to a blade server
which is running a single media-relay instance.

Under light load all is well. When the load starts ramping up (800+
calls) thing start going a bit pear-shaped, however. I end up with
massive numbers of entries like this in the syslog of the relay:
Cannot use port pair 53378/53379
Which appears to bog the whole relay down to the point where it's
using 100% of the core. Even after turning the calls back off, the
-relay remains at 100% and continues to dump more 'Cannot use port
pair' notices into rsyslog and is impossible to stop normally due to
it being so tied up. rsyslog was not loaded out in the 'top', so
although it was clearly being hammered by -relay, I don't think
rsyslog was the bottleneck here.

I guess my first question is, what am I doing wrong here to cause it
to be pushing literally tens of thousands of these errors?

And then, next, how do I best tune mediaproxy to handle larger loads?
I was thinking I could run several -relays on a single blade as they
appear to be single-threaded and, therefore, multiple forks will load
across the machine properly... but I'm not even sure if -relay can use
a different conf file to the default.

The dispatcher, which as I said lives on the OpenSIPS vm, looks like this:
[Dispatcher]
socket_path=/tmp/dispatcher.sock
listen=dispatcher.public.ip.address
management_use_tls=no
log_level=WARNING

The relay, on a Dell M610 blade, looks like:
[Relay]
dispatchers=dispatcher.public.ip.address
relay_ip=relay.public.ip.address
port_range=50000:60000
log_level=WARNING

Any suggestions would be gratefully received;

 - Jock