Restrictions and considerations

Certain restrictions and considerations apply to using the HD Tuning Aid utility.

HD Tuning Aid is applicable only to HDAM, HIDAM, PHDAM, or PHIDAM databases.

Your randomizing routine might have its own restrictions that can affect the way you must run HD Tuning Aid. It must be capable of processing the key values that you provide as input. If your randomizer refers to IMS control blocks, you are required to run HD Tuning Aid under the IMS batch region controller.

If the IMS management of ACBs is enabled, you must run HD Tuning Aid under the IMS batch region controller.

Keep in mind the following points when processing HALDBs:

• If you use multiple KEYSIN data sets created by multiple HD Pointer Checker runs, you must make sure that all the KEYSIN data sets you specify on the KEYSIN DD statement are concatenated in ascending order of the database number and partition ID.
• HD Tuning Aid can accept all or some of the partitions of a PHDAM or PHIDAM database as input. If you want to run an HD Tuning Aid job for particular partitions, first run an HD Pointer Checker job against those partitions to create a desired KEYSIN data set.
• When you process the KEYSIN data set of PHIDAM or PHDAM, or simulate conversion to PHDAM, you must run the HD Tuning Aid job under the IMS batch environment and specify DBRC=Y for PARM=(DLI,FABTROOT,&PSB,,,,,,,,,,,Y,N) of DFSRRC00. Also, RECON data sets are required. If the RECON data sets are not defined as dynamic allocation data sets, you must specify them in RECONx DD of step DFSRRC00.
• If the input PHIDAM or PHDAM database uses a partition selection exit, you must put the load module in the STEPLIB data set. If you intend to simulate the process that uses highkey without using the partition selection exit, you must put the load module in the STEPLIB data set. If you want to simulate the process by using another partition selection exit, you must put the partition selection exit in the IMS2 data set.