HP XP7 Storage - Manual (Page 37)

Table 20 Types of Compatible FlashCopy and Compatible FlashCopy SE options (continued)
Features Option type
Suppresses the background copy operations by Compatible FlashCopy, and prioritizes the
host I/O operations. For details, see
(page 37) .
FC Ext. Slower Copy1
Note: You need to set FC Ext. Slower Copy1 option invalid.
Suppresses the background copy operations by Compatible FlashCopy, and prioritizes the
host I/O operations. You can suppress more Compatible FlashCopy background copy FC Ext. Slower Copy2
operations by using this option instead of the FC Ext. Slower Copy1 option. For details, see
(page 37) .
FC Slower Copy1 option
The FC Slower Copy1 option is used to prioritize host I/O response over background copying
processing of Compatible FlashCopy relationships. When the FC Slower Copy1 option is in effect,
the maximum number of the Compatible FlashCopy relationships that can be copied simultaneously
in the background is halved, and consequently host I/O response improves. When the FC Slower
Copy2 option is in effect, the FC Slower Copy1 option becomes invalid.
When background copying processing of Compatible FlashCopy is suppressed by the FC Slower
Copy1 option, the time taken for background copying increases. However, since the background
copying processing time of relationships is not always same, the background copying processing
time is not necessarily doubled.
If Business Copy pairs exist in the same parity group, host I/O responses might not be improved.
FC Slower Copy2 Option
The FC Slower Copy2 option is used to prioritize host I/O response over background copying
processing of Compatible FlashCopy relationships. When the FC Slower Copy2 option is in effect,
the number of Compatible FlashCopy relationships that can be copied simultaneously in the
background is suppressed to one-quarter, and consequently host I/O response improves.
The two options, FC Slower Copy1 and FC Slower Copy2, have the same function. The difference
between them is that FC Slower Copy2 provides the best host I/O response because it suppresses
more background copy operations than the FC Slower Copy1 option. When the FC Slower Copy2
option is in effect, the FC Slower Copy1 option becomes invalid.
When background copy processing of Compatible FlashCopy is suppressed by the FC Slower
Copy2 option, the time taken for background copying increases. However, since the background
copy processing time of relationships is not always same, the background copy processing time
does not necessarily quadruple.
If Business Copy pair relationships exist in the same parity group, host I/O responses might not
be improved.
FC Ext. Slower Copy1 Option
The FC Ext. Slower Copy1 option is used to prioritize host I/O response over background copying
processing of Compatible FlashCopy relationships. When the FC Ext. Slower Copy1 option is in
effect and the MP operating ratio of the MP blade exceeds 65%, background copy operations are
suppressed, and consequently host I/O response improves.
When background copying processing of Compatible FlashCopy is suppressed by the FC Ext.
Slower Copy1 option, the time taken for background copying increases. When the FC Ext. Slower
Copy2 option is in effect, the FC Ext. Slower Copy1 option becomes invalid.
FC Ext. Slower Copy2 Option
The FC Ext. Slower Copy2 option is used to prioritize host I/O response over background copying
processing time of Compatible FlashCopy relationships. When the FC Ext. Slower Copy2 option
Selecting Prior operation 37