Advanced Topics › Performance Considerations › Separating CA MIM into Multiple Address Spaces

Separating CA MIM into Multiple Address Spaces

CA MIM components are often run together in the same address space. Under normal operating conditions, CA MIA adds minimal processing overhead to a shared address space and the performance impact is negligible. However, if the CA MIA TRACE facility is activated at the request of CA MIA support to provide documentation for a reported problem, then the processing overhead and performance impact of the trace can have significant impact. For this reason, it may be advantageous to separate the CA MIM product into multiple address spaces.

It is common, when running all components of CA MIM, to run CA MII in its own address space, and CA MIA combined with CA MIC in a separate address space. Sample CA MIM parmlib members are provided in the CAI.CBTDPARM data set.

Note: For more information, see the members MIACMNDS, MIAINIT, MIAPROC, and MIASYNCH in the CAI.CBTDPARM data set sample parmlib.

Note: Using the coupling facility, XCF, or CTC communication methods for CA MIM provide the best response times for managing enqueue, tape, and DASD resources. These methods are recommended for any CA MIM address space running CA MII, because enqueue processing requires the best possible response time. In most cases, however, tape processing does not require the faster response times that enqueue processing does. If you have CA MIA in its own address space, then you may find the shared DASD communication method provides satisfactory response time for tape allocation, freeing CTC, XCF, or coupling facility resources for applications where response time is critical.