Process Manager (PM)

PM performs the starting, continuation, and completion of process instances. It can be driven from a number of sources such as client requests or asynchronous EMS queues.

The main way to monitor the backlog of PM work is to run the following query: 
SELECT COUNT(1) FROM PVM_REQUEST_QUEUE WHERE status=0;
This returns all rows that have been scheduled but have yet to be picked up by the worker threads.