Using HP-UX Workload Manager: A quick reference

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How do I determine a goal for my workload?
NOTE
Be aware of the resource interaction for each of your workloads. Limiting a
workload’s memory allocation can also limit its use of CPU resources. For
example, if a workload uses memory and CPU resources (cores) in the ratio
of 1:2, limiting the workload to 5% of the memory implies that it cannot use
more than 10% of the CPU resources—even if it has a 20% CPU allocation.
To characterize the behavior of a workload, use the following example WLM configuration:
/opt/wlm/examples/wlmconf/manual_entitlement.wlm
Using this configuration, you can directly set an entitlement (allocation) for a workload using the
wlmsend command. By gradually increasing the workload’s allocation with a series of wlmsend
calls, you can determine how various amounts of CPU resources affect the workload and its
performance with respect to some metric that you might want to use in an SLO for the workload.
NOTE
This configuration file is only for PRM-based configurations. PRM must be
installed on your system. For a similar configuration file that demonstrates
WLM’s ability to migrate CPU resources across partitions, see the
par_manual_allocation.wlm and par_manual_allocation.wlmpar
configuration files in /opt/wlm/examples/wlmconf.
In addition, you can compare this research with similar data for the other workloads that will run on
the system. This comparison gives you insight into which workloads you can combine (based on their
needs for CPU resources) on a single system and still achieve the desired SLOs. Alternatively, if you
cannot give a workload its optimal amount of CPU resources, you will know what kind of
performance to expect with a smaller allocation.
Once you know how the workload behaves, you can decide more easily the type of goal (either
metric or usage) you want for it. You might even decide to just allocate the workload a fixed amount
of CPU resources or an amount of CPU resources that varies directly in relation to some metric. For
information on the different methods for getting CPU resources for your workload, see the “SLO
TYPES” section in the wlm(5) manpage.
Like the manual_entitlement.wlm configuration, the following configuration enables you to adjust a
workload group’s CPU allocation with a series of wlmsend calls:
/opt/wlm/toolkits/weblogic/config/manual_cpucount.wlm
However, manual_cpucount.wlm uses a pSet as the basis for a workload group and changes the
group’s CPU allocation by one whole core at a time.
What are some common HP-UX Workload Manager tasks?
WLM is a powerful tool that enables you to manage your systems in numerous ways. The following
sections explain some of the common tasks that WLM can do for you.
Migrating Cores across partitions
WLM can manage SLOs across virtual partitions and nPartitions.