The PMDF CONFIGURE QUEUES utility is a convenient way to configure PMDF to use PMDF Process Symbiont queues; see Section 9.1.1 below. Of course, you can also manually define queues that use the PMDF Process Symbiont; see Section 9.1.2 below.

Due to the limitations of OpenVMS server symbionts, a PMDF Process Symbiont queue cannot execute more than one job at a time. Therefore, for adequate message throughput, multiple simultaneous jobs should be allowed by creating several PMDF Process Symbiont execution queues with a single generic queue referencing all of them. Jobs submitted to the generic queue will be scheduled to run on the execution queues in parallel. Since PMDF submits jobs to MAIL$BATCH by default, that is typically used as the name of the generic queue.

Note that the benefits inherent in reusing server processes can be reduced if you create too many parallel execution queues. You need to balance your use of parallel and serial jobs in order to maximize throughput. You should see peak optimization when jobs can be scheduled across all parallel execution queues without pending too long in the generic queue. On the other hand, new jobs should still enter each execution queue within the server timeout period so that each execution queue's cached process is given something to do before timing out and deleting itself.

Symbiont server processes log output to the file

PMDF_LOG:task_server_queue-name.log

where queue-name is the name of a specific server queue. Command procedures executed by the server process continue to write their log output to files in the PMDF log directory such as post.log and return.log.