Increasing max-open files for beanstalkd

Quick tip: If you are running out of file descriptors in your Beanstalkd process, use
/etc/default/beanstalkd to set the ulimit before the init script starts the process.

e.g.

# file: /etc/default/beanstalkd
BEANSTALKD_LISTEN_ADDR=127.0.0.1
BEANSTALKD_LISTEN_PORT=11300
START=yes
BEANSTALKD_EXTRA="-b /var/lib/beanstalkd -f 1"

# Should match your /etc/security/limits.conf settings
ulimit -n 100000

Lots of resources online tell you to update your /etc/security/limits.conf and
/etc/pam.d/common-session* settings to increase your maximum number of available file descriptors.
However, the default beanstalkd installation on Ubuntu 12.04+ uses an init script that starts the
daemon process using start-stop-daemon which does not use your system settings when setting the
processes ulimits. Just add this line to your defaults and you're good to go!