HP XP Application Performance Extender Software - Manual (Page 61)

Enabling DLOM settings
There are three different modes to enable DLOM:
• DLOM only mode (Non QoS MPBs) — In this mode, P9000 Application Performance Extender
operates as a load balancer, where MP blade utilization for I/O processing is balanced by
changing LDEV ownership across multiple MP blades. This reduces load on overloaded MP blades.
• QoS-DLOM mode (QoS MPBs) — In this mode, you prioritize the performance of critical applications
and achieve the defined SLO targets, while P9000 Application Performance Extender operates
as a load balancer to reduce load on overloaded MP blades.
• Partial-QoS-DLOM mode — In this mode, P9000 Application Performance Extender operates as
a load balancer, while you can prioritize the performance of applications only on a selected set
of MP blades.
NOTE:
In Partial mode, ensure that the applications where I/O prioritization is required are running on
LDEVs owned by the MP blades present in the QoS MPB compartment. For more information on
changing LDEV ownership, see
Appendix E
If there are no MP blades present in the Non QoS MPBs compartment, the mode is QoS-DLOM. If
there are no MP blades in the QoS MPBs compartment, the mode is DLOM only.
You can move MP blades from the Non QoS MPBs compartment to the QoS MPBs compartment and
vice versa. For the change to be effective, ensure that you click Submit.
Load balancing only
The amount of I/Os that are generated by applications are dynamic. This will lead to an imbalance
in MP blade utilization.
If you add or remove applications generating I/Os frequently, there is a need to balance MP blade
utilization.
NOTE:
You can use the load balancing feature of P9000 Application Performance Extender even if the
applications generating I/Os are hosted on platforms or operating systems where P9000 Application
Performance Extender I/O prioritization is not supported.
1. Select the array.
2. Ensure that all the MP blades are in the Non QoS MPBs compartment.
3. Click Submit.
4. Select the Non QoS MPBs Load balancer check box.
I/O prioritization only
If you do not want to change your pre-configured LDEV-MPB mapping, but want I/O prioritization,
do the following:
1. Select the array.
2. Ensure that all the MP blades are in the QoS MPBs compartment.
HP StorageWorks P9000 Application Performance Extender Software User Guide 61