Stuck-Call Generator

Background

On Adhearsion 2.6.1, "stuck calls" are occasionally observed". A "stuck call" is one which has been released by Asterisk, but is still perpetually tracked by Adhearsion.

One situation that seems to produce stuck calls is when a SIP peer calling an Adhearsion-backed Asterisk instance has sent an INVITE, quickly followed by a CANCEL. However, there is a brief amount of pause time that must be present between the INVITE..CANCEL in order for the situation to occur, such that the Asterisk AGI(agi:async) command is invoked, but that the call is over by the time that Adhearsion has launched the CallController.

Software

Adhearsion 2.6.1
Asterisk 1.8
JRuby 1.7.24
stuck-call-scenario/adhearsion (This simple ahn application)
- Nothing novel in this app, other than a Cache::Stats module that periodically reports how many calls Adhearsion considers to be active.

Invocation

1. Checkout and Setup

git clone https://github.com/sfgeorge/stuck-call-scenario.git
cd stuck-call-scenario/adhearsion
bundle install

2. Start Adhearsion

export AHN_PUNCHBLOCK_USERNAME=**<Asterisk-AMI-Username>**
export AHN_PUNCHBLOCK_PASSWORD=**<Asterisk-AMI-Password>**
export AHN_PUNCHBLOCK_HOST=**<Asterisk-hostname>**
export JRUBY_OPTS='--server --headless -J-XX:+PrintCommandLineFlags -Xcompile.invokedynamic=false'
export AHN_PLATFORM_LOGGING_LEVEL=trace

screen -A -m -d \
  -S stuck-call-scenario \
  bundle exec ahn start . &

3. Send 1 call into Adhearsion

../sipp/stuck-call-generator.sh
tail -f log/adhearsion.log

Reproducible Results

If the above test was 'successful' in reproducing failure, then you will see that adhearsion.log reports > 0 calls, even when asterisk -rx 'core show channels count' reports no calls.

If you have not produced any stuck calls, then you may need to be a bit more aggressive:

Running more calls

TOTAL_CALLS=30 ../sipp/stuck-call-generator.sh

Using more diverse timing for quick-hangups

You may need to modify the amount of time before we perform a quick-hangup. You can do so by editing ../sipp/stuck-call-generator.xml and changing this line:

<pause distribution="uniform" min="1" max="10" />

...the units are in milliseconds. Consider changing "10" to something larger like "100".

After you save, you can re-run for a more diverse distribution of "quick" hang-ups, between 1 to 100 milliseconds:

TOTAL_CALLS=100 ../sipp/stuck-call-generator.sh

sfgeorge / stuck-call-scenario