Estimating storage requirements for CMCI

To avoid possible storage problems when you use the CICS® management client interface, you must specify appropriate levels of 64-bit (above-the-bar) storage in the CICS region, and auxiliary storage. Use the z/OS® MEMLIMIT parameter to set the limit for 64-bit storage in your WUI server or CICS region, and the MAXAUXCPSM and MAXAUXTOTL CICSPlex® SM system parameters to set auxiliary storage for the CMAS.

1. Calculate the storage requirement for a typical request.
   Select the resource that is likely to generate the largest number of records in a request and multiply the number of records by the size of each record. See the appropriate table in CICSPlex SM resource tables to determine the record size.
2. Calculate your total requirements for 64-bit storage for retained result sets.
   Estimate your expected maximum number of retained result records for a single request and multiply this figure by your estimate of the storage required for each request. For example, if you can have 100,000 CICS terminals in a single request, multiply this figure by the size of the resource record as determined in step 1.
3. If you are setting up CMCI in a CICSPlex SM environment, estimate your auxiliary storage requirements for your CMAS.
   Estimate the maximum number of concurrent requests that you can expect and multiply this figure by your estimate of the storage required for each request as calculated in step 2. You can derive your estimate of concurrent requests from the total number of users that you expect to be using CMCI at any one time and how many simultaneous requests they are likely to make.
4. Consider adding more storage for metadata.
   CMCI stores all requested resource records for each request for a new retained result. For the initial request of a new resource type, for example, a first request for CICS programs, a small amount of attribute metadata is also stored. For large requests, the size of the attribute metadata and any other storage used while making the request is negligible compared to the storage required for records themselves. Consider adding an extra 2% to your final estimate to cover any extra metadata used internally by CMCI on the WUI server. This extra metadata is not necessary for the CMAS calculation.