When the first PMDF Process Symbiont server queue is started, then the file pmdf_process_smb.opt in the PMDF table directory is consulted for option settings. If the file does not exist, the symbiont will use internal defaults. The file contains lines of the form

option = value

An exclamation mark, !, introduces a comment line. Blanks and tabs are ignored as well, except within the value string, where they are compressed to a single blank.

In addition to option settings, the file can contain a line consisting of a Process Symbiont queue name enclosed in square-brackets of the form

[queue-name]

Such a line indicates that option settings following this line are to apply only to the queue named by queue-name . Initial option settings that appear before any such queue name tag will apply globally to all queues controlled by the Process Symbiont. Per queue option settings will override global defaults for that queue. Option and queue names are not case sensitive.

A sample Process Symbiont option file is shown in Figure 9-1.

Figure 9-1 Sample Process Symbiont Option File

! ! Global defaults for all queues: ! idle_timeout = 0 05:00:00 (1) ! ! Now queue specific settings: ! [PMDF_1] (2) !first queue lifetime = 0 12:00:00 (3) ! [PMDF_2] (4) !second queue process_priority = 3 (5) idle_timeout = 0 00:00:01 (6)

The key items in the above example are

1. Set the idle timeout for all queues to 5 hours. This effectively allows PMDF to avoid process creations for PMDF jobs nearly all of the time.
2. Subsequent options will apply only to the queue named PMDF_1.
3. Set the life time to 12 hours for jobs in the PMDF_1 queue. This will cause the server process to exit and restart at most every 12 hours.
4. Subsequent options will apply only to the queue named PMDF_2.
5. Set the process priority to 3 for jobs in the PMDF_2 queue.
6. Set the idle timeout to one second for jobs in the PMDF_2 queue. This will cause a single process to be reused only when PMDF has a constant stream of work for this queue. Most of the time there will be no process idle on this queue.

The available options are:

IDLE_TIMEOUT

An OpenVMS delta time which specifies the interval that a server process will wait for another task after it completes a task. If the IDLE_TIMEOUT period expires the server process will be deleted and a new process must be created the next time a task is to be processed. If no IDLE_TIMEOUT is specified, the built-in default of one minute will be used.

PROCESS_PRIORITY

An integer value between 0 and 15 which specifies the OpenVMS process priority for the server task. If no priority is specified, the built-in default of 4 will be used.

LIFETIME

An OpenVMS delta time which specifies the maximum period over which a single server process will be used. If LIFETIME expires for a server process it will be deleted when it finishes the current task. The next task will then cause a new server process to be created. The task process' log file will be closed and a new log file started. If no LIFETIME is specified, the built-in default of 24 hours will be used.