Mbox Sets and Message Queues

The foreground and background processes communicate with each other using messages. Messages contain information about the iProcess case and instructions about what to do with the case (such as release, keep or forward it.) A message is processed by the case instruction processors. Mbox set is the generic name used for a container in which these messages are stored. Processes can dequeue messages from a Mbox set as and when resources are available.

The messages are stored and managed in the following way:

• in the UNIX Oracle and Windows Oracle versions, using Oracle AQ. Oracle AQ uses message queues, which are defined as Oracle AQ tables.
• in the UNIX DB2 and Windows SQL Server version, using iProcess database tables that are managed by the database server.
Note: See the appropriate TIBCO iProcess Engine Database Administrator guide for more information about the format of the AQ or database tables that are used to hold the message queues.

The TIBCO iProcess Engine uses a logical and physical grouping for queues to help improve message throughput. The physical message queues are grouped together as logical Mbox sets.

An Mbox set can be used for different purposes. For example, two Mbox sets can be created for the Backgrounds. The Deadline Manager (DLMGR) can write to one set while other processes could write to the second set. The relative priority of processing the work can be changed by assigning different numbers of background processes to dequeue the messages in the different Mbox sets.

Processes can be configured to enqueue or dequeue messages to/from a specific Mbox set rather than to/from a single Mbox queue. The sets can be changed as the performance demands change in your system environment. Multiple queues in an Mbox set enable processes to distribute messages in a round robin manner resulting in an even distribution of messages on the queues.

For more information about Mbox sets, see the iProcess Mbox Sets.