Improving allocation performance

You can contribute to the efficiency of allocation processing throughout your installation in several ways:
  • For devices:
    • Use the device preference table, specified through the Hardware Configuration Definition (HCD) to set up the order for device allocation. See the z/OS MVS Device Validation Support appendix for a listing of the device preference table installation's devices as esoteric groups, and to group them for selection by allocation processing.
    • Use the eligible device table (EDT) to identify the I/O devices that you want to include in the esoteric groups.

      For more information on the device preference table and the EDT, see z/OS HCD Planning.

  • For volumes, use the VATLSTxx members of SYS1.PARMLIB to specify volume attributes at IPL.
  • For data sets, you can specify the JCL used for your installation's applications according to the device selection criteria you have set up through the HCD process and IPL.
Parent topic: Allocation considerations