[Freeswitch-users] Generating bulk calls on freeswitch to check load

Hi all, I have installed freeswitch on Google cloud compute. I wanted to know how can I make bulk calls on freeswitch. My goal is to scale up/down server instances based on load on freeswitch server. For that i want to know if there are any tools that i can use to generate bulk calls. Please let me know if anyone has idea about this. Thanks