This step helps you identify data sets that are not candidates for re-direction to the DASD buffer. They are either too large, belong to jobs with special requirements, or are DFSMShsm-owned.

Identify exception tape data sets to your ACS routines by filters and assign them to a null storage class to bypass system management. Data sets assigned a null storage class are written to tape as before.

To achieve optimal tape performance, create these data sets using advanced cartridge subsystems, such as the 3490E with Enhanced Capacity Cartridge System Tape.

To identify exception tape data, perform your volume mount analyzer simulations in the following sequence:

1. Identify and exclude large data sets
2. Develop filters for large data sets
3. Identify and exclude special jobs or data sets
4. Finalize exclusion filter list