Host i/o performance option, Figure 9 – HP StorageWorks XP Remote Web Console Software User Manual
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Quick Restore Operation
P-VOL
S-VOL
PSUS
P-VOL
S-VOL
PAIR
Legend
: Time flow
: User Data
With Swap&Freeze Option
Without Swap&Freeze Option
P-VOL
S-VOL
PAIR
P-VOL
S-VOL
PAIR
Figure 9 Quick Restore Operation With or Without Swap&Freeze Option
The Quick Restore pairresync operation on a pair with status PSUS exchanges the data in the P-VOL and
the S-VOL of the pair. If you use Swap&Freeze option when performing the Quick Restore pairresync
operation, the update copy operation will not take place after the Quick Restore pairresync operation
is complete. Therefore, the data of the P-VOL and the S-VOL is kept exchanged. If you do not use
Swap&Freeze option when performing the Quick Restore pairresync operation, the update copy
operation will take place after the Quick Restore pairresync operation is complete, and the data in the
P-VOL overwrites the S-VOL.
Host I/O Performance Option
The Host I/O Performance option improves host I/O responses over Business Copy copy processing time.
When the Host I/O Performance option is used, the storage system suppresses Business Copy copy
processing, and consequently the host I/O responses improve.
Note:
When Business Copy copy processing is suppressed by the Host I/O Performance option, the time
taken for copying increases. Also, if ShadowImage for Mainframe pairs exist, host I/O responses might
not be faster. In this case, set the Host I/O Performance option for ShadowImage for Mainframe as well.
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About Business Copy Operations