HP XP P9500 Storage - Manual (Page 33)

Table 18 Whether Reverse Restore and Fast Reverse Restore can be performed when a Compatible
FlashCopy volume is used as a CC or XRC volume
CC / XRC Compatible FlashCopy
S-VOL P-VOL
NO
2
NO
1
S-VOL
N/A N/A
1
T-VOL
1. NO - cannot be performed.
N/A - cannot be shared
2. Do not execute Reverse Restore or Fast Reverse Restore when an S-VOL is shared by Compatible FlashCopy and
CC or XRC. If you execute Reverse Restore or Fast Reverse Restore when an S-VOL is shared by Compatible
FlashCopy and CC or XRC, the data in the S-VOL will be overwritten by the two programs and destroyed.
Using Compatible FlashCopy with Thin Provisioning Z
When you use a Compatible FlashCopy T-VOL as a THP V-VOL, the host cannot access it if the
relationship status becomes suspended because the pool becomes full. To recover from suspended
status, you must release the Compatible FlashCopy relationship.
Optimizing Volumes
Volumes can be optimized by Compatible FlashCopy if you use the DEFRAG command of the
DFSMSdss utility with the FASTREPLICATION option. See the IBM FlashCopy manual for details of
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 including the volume is overloaded when accessed too many times.
•
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), you must reduce
workloads on the parity group.
Optimizing Volumes 33