Improving Batch Performance by Using Sequential Data Striping

You should select the data sets that benefit from sequential data striping based on your knowledge of how batch jobs use these data sets. Use the following criteria to select your candidates for sequential data striping:

Select large, physical sequential data sets
The VTOC must be accessed for each volume that contains a part of the striped data set. There is a slight performance penalty because of this additional processing that is not offset for small data sets.
Select data sets processed using BSAM or QSAM only (no EXCP)
Select data sets for jobs that are I/O-bound
Read the RMF™^™ Device Activity Report statistics to find how long the jobs were executing. Volumes with high device CONNECT times are candidates for sequential data striping. Use caution in interpreting these statistics. If the high CONNECT time results from I/O contention because of other data sets on the volume, sequential data striping cannot improve performance. Therefore, it is beneficial to have a separate storage group for striping. It is also beneficial to have volumes in this storage group from as many different storage controls and serially connected channels as possible. A single storage control supports up to four paths. Therefore, you can have up to four volumes per data set per storage control.
Select data sets used by applications that can coexist with a system-determined block size
Blocks for striped data sets contain additional control information. Applications and JCL might require changes to block size and buffer size specifications to ensure that striped data sets are efficiently stored on DASD.

Tip: You can use the DFSMS Optimizer Function to help you select data sets that can benefit from striping.