Chapter 14. Performance considerations for System z servers 511
instead of just the actual track on which the I/O operates. This design prevents other I/Os
from running simultaneously, if a write I/O is being executed against that volume or
dataset, even when PAV is used. You need to identify such applications and allocate the
datasets on volumes where they do not conflict with other applications. Custom volumes
are an option. For an Independent software vendor (ISV) product, asking the vendor for an
updated version might help solve the problem.
Consider these other benefits of using large volumes:
Reduced number of required UCBs. We reduce the number of UCBs by consolidating
smaller volumes to larger volumes, and we also reduce the number ...