Online execution requirements for MFSTEST mode

When you want to perform testing of MFS formats during execution of the online IMS production system, the IMS.TFORMAT library must be defined and must contain the appropriate test blocks.

These can be named the same as existing production formats. The IMSTFMTA/B DD statements must be present in the control region JCL, with the IMS.TFORMAT library as the first data set, followed by the corresponding IMS.FORMATA/B library concatenated to it.

The CIOP is used to hold all format blocks for terminals operating in MFSTEST mode. Storage space in CIOP is dynamically allocated according to your system demands.

Executing in MFSTEST mode does result in a performance impact, because both transmission and message formatting are being stored in the same buffer.