Using HP Integrity Essentials Global Workload Manager 3.0.1 with Global Instant Capacity 8.02.01

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later, you might want to adjust the resource allocation interval when an SRD includes nPartitions from
a complex that is part of a GiCAP group.
For information on configuring gWLM, see the gWLM User’s Guide or the online help.
For information on creating and configuring GiCAP groups, see the iCAP User's Guide.
Operational Considerations
The following sections discuss various behaviors to be aware of when using gWLM and GiCAP
together.
When to Increase the Resource Allocation Interval in gWLM
An SRD that includes one or more partitions whose complex is in a GiCAP group is likely to require a
longer allocation interval as a result of the time needed to complete iCAP operations within a GiCAP
group. gWLM monitors the proportion of the allocation interval that is needed to complete the
reallocation of resources. When that proportion exceeds 50%, gWLM generates the following
warning:
SRD Resource Interval Warning: gWLM made a one-time adjustment to the
allocation interval because allocation changes were taking longer than
recommended. This adjustment avoided potentially incorrect allocations.
Consider increasing the interval in your configuration.
You can see this message as an HP SIM event if you have gWLM configured to create events. Also,
the message appears in the file /var/opt/gwlm/gwlmagent.log.0.
If this condition arises consistently, such warnings will recur approximately every 30 minutes. In this
case, you should increase the allocation interval. You should select an allocation interval for which
the occurrence of this message is relatively rare. (However, gWLM does accommodate occasional
delays in resource reassignment with little adverse effect.) The following section provides information
on the factors to consider when choosing a new allocation interval.
Determining an Appropriate Resource Allocation Interval
The appropriate length for a resource allocation interval depends on the configuration of the SRD and
the GiCAP group as well as the frequency with which gWLM resource requests initiate GiCAP
operations.
Consider that gWLM performs resource management for an SRD periodically at a specified interval
by:
1. Sampling the resource utilization of all the workloads in the SRD
2. Determining a CPU resource reallocation plan for the workloads based on their measured
utilization as well as the priorities you specify in policies
3. Implementing the reallocation plan
As discussed previously, gWLM suggests a resource allocation interval that does not consider whether
the managed partitions in an SRD are part of a GiCAP group. Consequently, you might want to
increase the interval yourself.
gWLM can sample utilization and determine a reallocation plan relatively quickly. Thus, the time to
actually implement the reallocation plan is the main determinant of a desirable resource allocation
interval. The interval needs to be long enough that:
1. The reallocation plan can be implemented
2. The subsequent utilization measurement for each workload reflects the use of its newly allocated
resources