Distributing the I/O

By distributing your data sets, you can prevent I/O requests from being queued in z/OS®.

Procedure

To distribute I/O operations:

  • If you do not have parallel access volumes, allocate frequently used data sets or partitions across your available disk volumes so that I/O operations are distributed.
    Even with RAID devices, in which the data set is spread across the physical disks in an array, data should be accessed at the same time on separate logical volumes to reduce the chance of an I/O request being queued in z/OS.
  • Consider isolating data sets that have characteristics that do not complement other data sets.