Use the following tips to optimize your mainframe and distributed IMS applications:
- Ensure that IMS TM applications are serially reusable - this is where the application loops through the message queue until all messages are processed before issuing a GOBACK, and releasing the Message Processing Region (MPR) for another program. When an application is not coded in this way, there is an increased overhead with every transaction.
- Ensure that your Program Specification Block (PSB) does not contain Program Control Block (PCB) lists that contain references to unused databases, or that it contains unused PCBs that point to the same database. If it does, this can result in Application Control Blocks (ACB) that take up more storage space than is necessary. This problem can occur when a generic PSB has been cloned (for convenience) and your application does not require all the database access specified.
