1.11. Data striping
Usually, in a multi-extent, multi-volume VSAM data set processed in sequential access, processing does not allow for any type of parallelism for I/O operations among the volumes. This means that when an I/O operation is executed for an extent in a volume, no other I/O activity from the same task or same data set is scheduled to the other volumes. In a situation where I/O is the major bottleneck, and there are available resources in the channel subsystem and controllers, it is a waste of these resources.
Data striping addresses this sequential access performance problem by adding two modifications to the traditional data organization:
The records are not placed in key ranges along the volumes; instead they are organized in ...
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