I have php script running as a cron job, extensively using third party code. Script itself has a few thousands LOC. Basically it\'s the data import / treatment script. (JSON to
Regular "top" command can show you, if CPU usage by php or mysql is bottleneck. If not, then delays may be caused by http calls.
If CPU usage by mysqld is low, but constant, then it may be disk usage bottleneck.
Also, you can check your bandwidth usage by installing and using "speedometer", or other tools.