HP XP Continuous Access Software - Manual (Page 72)

72 Continuous Access XP for the XP1024/XP128
NOTE: Specify a value not exceeding the I/O Delay Increase for the I/O Delay Start. Specify a value
not exceeding the Pending Update Data Rate for the I/O Delay Increase. If sidefile threshold is set
between 0 to 30%, influence to the I/O delay is kept low.
HP recommends that you change the I/O Delay Start and I/O Delay Increase when all Continuous Access
XP asynchronous pairs are suspended, or host I/O and sidefiles do not exist. If you do not want to control
inflow into a sidefile, specify the value same as the Pending Update Data Rate for the I/O Delay Start and
I/O Delay Increase, and specify 0 second for the Offloading Timer.
1. From the Consistency Group list, right-click, and click Async Option. The Async Option pane appears.
NOTE: You do not have to select a consistency group on the list.
2. In the Async Option pane, select parameters.
3. Click Set to set parameters. The list changes to the Asynchronous Option Settings Parameter list.
NOTE: After being set, options can be modified and canceled (see ” Modifying parameters and
deleting consistency groups ” on page 72).
4. Click Apply on the Continuous Access XP main pane to apply option settings to the disk array.
When the Async Option pane closes, the list changes to the Asynchronous Option Settings Parameter list.
Figure 44 Asynchronous Option Settings Parameter list
• Pending Rate: Sidefile allocation in %. Indicates sidefile threshold, which is maximum amount of cache
used for storing Continuous Access XP asynchronous recordsets (sidefiles).
• Offloading: Offloading timer in seconds. Indicates that the MCU waits to send a Continuous Access XP
Async recordset to the RCU.
• Delay Start (for XP1024/XP128, use firmware version 21.07.04 or later only): Maximum amount of
cache for starting inflow control for the asynchronous copy.
• Delay Increase (for XP1024/XP128, use firmware version 21.07.04 or later only): Maximum amount
of cache for starting to strengthen control over inflow for the asynchronous copy.
Modifying parameters and deleting consistency groups
After the Consistency Group (CT Group) and Asynchronous Option operations, parameters can be
modified individually, and consistency groups set by the operation can be deleted.
Modifying parameters
1. After performing the CT Group operation, click a consistency group on the list. To modify parameters
for Async Option operation, you do not have to select the row on the list.
2. Right-click, and click Modify. A pane for each operation appears.
3. Modify parameters, and click Set.
4. Click Apply on the Continuous Access XP main pane to apply modifications to the disk array.
Deleting consistency groups
1. Click the consistency groups on the list.
2. Right-click, and click Delete. Selected consistency groups are deleted from the list, and the consistency
groups are out of operations.
3. Click Apply on the Continuous Access XP main pane to apply the deletion to the disk array.