Adding consistency groups, Adding – HP StorageWorks XP Remote Web Console Software User Manual
Page 104
cache that is used for async recordsets reaches the specified value of the threshold, the MCU
controls the cache inflow. It follows that the delay of I/O time of MCU occurs.
The I/O Delay Increase option allows you to specify the threshold (30-70%), which is the maximum
amount of cache for starting to strengthen control over the inflow for the asynchronous copy. When
the amount of cache that is used for async recordsets reaches the specified value of the threshold,
the MCU controls the cache inflow. It follows that the delay of I/O time of MCU increases.
Specify a value not exceeding the value of I/O Delay Increase for the value of I/O Delay Start.
Specify a value not exceeding the value of Pending Update Data Rate for the value of I/O Delay
Increase. If the sidefile threshold is set between 0 to 30%, the influence to the I/O delay is kept
low.
HP recommends that you change the values of I/O Delay Start and I/O Delay Increase when all
asynchronous pairs of XP Continuous Access are suspended, or neither the host I/O nor sidefiles
exist. If you do not want to control the inflow into a sidefile, specify the same value as the Pending
Update Data Rate for both values of I/O Delay Start and I/O Delay Increase, and 0 seconds for
the Offloading Timer.
To set the async options:
1.
Click the Asynchronous Operation tab. You do not need to select anything in the tree.
2.
Right-click the CT group list (you do not need to select anything), and click Async Option to
open the Async Option dialog box (see
“Async Option Dialog Box” (page 103)
). The async
options can only be modified when no XP Continuous Access Asynchronous pairs or groups
exist in the connected CU (P-VOLs or S-VOLs).
3.
On the Async Option dialog box, select the desired parameters. For further information on
the asynchronous copy options, see above and
“Inflow Control of Recordsets” (page 23)
4.
Click Set to close the Async Option dialog box. (Click Cancel to cancel the async option
operation.) The preview list displays the requested async option operation.
5.
Verify the requested operation displayed in the preview list.
6.
To change the async operation option, select the operation from the preview list, right-click,
and click Modify. To remove the operation, select it from the preview list, right-click, and click
Delete. To cancel all operations, select all the operations in the preview list, right-click, and
click the Delete command, or click the Cancel button.
7.
To apply the settings, click the Apply button.
Adding Consistency Groups
The Add CT Group dialog box (see
) allows you to add consistency groups
and select the options for the new groups. To open the Add CT Group dialog box, click the
Asynchronous Operation tab, click Display All or Not Used in the tree, select the group(s) to be
added, right-click the group(s), click CT Group Operation, and click Add CT Group.
104 Performing XP Continuous Access Configuration Operations