Changing the priority of
an SPM group
All host bus adapters in one SPM group must have the same priority. Prioritized WWNs and non-prioritized WWNs cannot be mixed in one SPM group.
You can use an SPM group to change the priority of multiple HBAs between prioritized and non-prioritized.
You can perform the upper-limit value control for the an SPM group by setting the upper-limit value on the an SPM group .
The upper-limit value of each HBA which belongs to the SPM group is the upper-limit value set for the SPM group divided by the number of HBAs which belong to the SPM group and have I/O.
The I/O existence in HBA is distinguished with one minute interval monitoring. The upper-limit value of HBAs which belong to the SPM group is updated in one minute interval.
So, when the existence of I/O is alternated the upper-limit value of SPM group might be over or under the setting value.
For example, in the condition that the upper-limit value is set 200 IOPS for the SPM group which 2 HBAs belong to and only 1 HBA has I/O, the upper-limit value allocated to each HBA is 200 (200 ÷ 1) IOPS. After that, if the number of HBAs which have I/O turns from 1 to 2, until the next detection (updating of HBA upper-limit value which belongs to the SPM group is in one minute interval), the upper-limit value might become 400 (200+200) IOPS because the upper-limit value is allocated 200 IOPS to each HBA. That is over the setting value for the SPM group.
Or, in the condition that the upper-limit value is set 200 IOPS for the SPM group which 2 HBAs belong to and 2 HBAs have I/O, the upper-limit value allocated to each HBA is 100 (200 ÷ 2) IOPS. After that, if the number of HBAs which have I/O turns from 2 to 1, until the next detection (updating of HBA upper-limit value which belongs to the SPM group is in one minute interval), the upper-limit value might become 100 IOPS because the upper-limit value is allocated 100 IOPS to each HBA. That is under the setting value for the SPM group.
Before you begin
- Required role: Storage Administrator (System Resource Management)
- You must enable the Device Manager - Storage Navigator secondary window. For details, see the Hitachi Device Manager - Storage Navigator User Guide of your storage system.
Procedure
Click to open the Server Priority Manager window.
Click
to change to Modify mode.
In the Server Priority Manager window, click Server Priority Manager. The Server Priority Manager main window appears.
Select the WWN tab.
In the lower-left tree, select and right-click the desired SPM group (
).
Change the priority:
- To change priority from prioritized to non-prioritized, select from the pop-up menu.
- To change priority from non-prioritized to prioritized, select from the pop-up menu.
Click Apply to apply the settings to the storage system.