Interpreting transaction statistics

Transaction statistics help you find out storage usage by transactions and identify storage issues and violations.

In Transaction manager: Global statistics, the Times the MAXTASK limit reached statistic indicates whether MXT is constraining your system, or any possible integrity exposures are resulting from forced resolutions of UOWs relating to the transactions. The only time that you must constrain your system in this way is to reduce virtual storage usage.

As most CICS® virtual storage is above the 16 MB line you may be able to run your system without MXT constraints, but note that CICS does preallocate storage, above and below the 16 MB line, for each MXT whether it is used. Changing MXT affects your calculations for the dynamic storage areas. See Setting the maximum task specification (MXT) for more information.

You can use the statistics in Transactions: resource statistics to find out which transactions (if any) had storage violations. It is also possible to use these statistics for capacity planning purposes. But remember, many systems experience both increasing cost per transaction as well as increasing transaction rate.