HP StorageWorks XP Remote Web Console Software - Manual (Page 63)

Optimization of Volumes
Volumes can be optimized by Version 2 if you use the DEFRAG command of the DFSMSdss utility
with the FASTREPLICATION option. See the IBM manual for details about the option.
CAUTION: The DEFRAG command may generate an error because the number of relationships
per volume exceeds the maximum when all the following conditions are met:
•
The parity group that includes the volume is overloaded with many accesses.
•
The DEFRAG command is executed with FASTREPLICATION(REQUIRED).
To avoid an error, avoid using the FASTREPLICATION option or specify
FASTREPLICATION(PREFERRED). If you specify FASTREPLICATION(REQUIRED), reduce the workloads
on the parity group.
Optimization of Volumes 63