Async CPM jobs are processed by Oracle's SPM queue, but the actual PHP code runs on any number of utility servers (likely based on some load-balancing logic for the pod). The custom CPM code itself runs in a looping PHP process that executes jobs from the queue, which means that the code stays in memory for a period of time. (To my knowledge, Oracle hasn't published any information as to exactly how long these processes run, however.) This causes two important results:

The toolbox has been doing really well and I want to thank everyone for their support by releasing a new tool for free. In the last month alone we gained 81 new users and have users from 22 different countries and 19 states in the US. The ROQL Tester is the favorite tool by about 50% with the Account Creator next in line and then the Account Unlock and PHP Stub generator. And most exciting (for me): we’ve got 70% of users on the new 2.0 toolbox. I’ve attached our analytics report to this post if anyone is interested in concrete numbers.