Using HP Global Workload Manager with Serviceguard

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that contains Instant Capacity processors. Processors may be activated and deactivated as often as
needed as long as the block of temporary capacity has a positive balance.
What is HP Global Workload Manager?
gWLM enables you to centrally define resource-sharing policies that you can use across multiple HP
servers. These policies increase system utilization and facilitate controlled sharing of system resources.
In addition, gWLM provides both real-time and historical monitoring of the resource allocation.
Why Use HP Global Workload Manager with HP
Serviceguard?
Combining gWLM and HP Serviceguard results in more efficient high availability, which includes:
• Lowering the costs of standby systems (or partitions)—In active/standby configurations, the standby
systems go unused until a failover occurs. Using HP TiCAP software can help reduce the costs of
standby systems because it allows you to pay for only the CPU resources that are used. With
gWLM, you can minimize the costs of using these CPU resources by optimizing the activation and
deactivation of the resources.
• Reducing the performance impact of an application failover in active-active configurations—
Consider a two-system Serviceguard cluster in which each system is running a combination of
packaged applications in an active/active configuration. (An active/active configuration has an
active system or partition as the secondary server, rather than an inactive system or partition just
standing by waiting for a failover.) If a package fails over from one system (or partition) to another
system (or partition), gWLM can automatically reallocate resources as needed. On the system
where the package was located originally, gWLM recognizes the package is no longer utilizing
resources. gWLM is then free to assign the unused resources to the remaining workloads subject to
the policies. Similarly, on the package’s new system, gWLM recognizes the package’s need for
additional resources. The system’s resources are then redistributed, based on gWLM policies
applied to the workloads. As a result, the high-priority packages can maintain their performance
objectives, even in a failover scenario.
• Reducing the cost of disaster tolerance in active/standby configurations and the performance
impact of application failover in active/active disaster-tolerant configurations—Serviceguard
clusters can be deployed in disaster-tolerant configurations using the Extended Cluster, Metrocluster,
or Continentalclusters products. The benefits discussed in the preceding paragraphs for
active/standby and active/active configurations carry over to the multi-site disaster-tolerant
configurations.
• Increasing utilization of a system that receives failover packages—When a system becomes
unavailable and its packages fail over to other servers in the cluster, gWLM can detect which
packages are in need of resources. However, if resources remain after satisfying high-priority
packages, gWLM grants the surplus resources to lower priority packages. You can also provide a
minimum amount of resources to the lower priority packages to guarantee that these packages do
not get starved in a failover scenario.
• Simplifying the configuration of failover scripts—if your current failover scripts shut down low-
priority packages to make resources available for high-priority packages that have failed over,
using gWLM can allow you to keep all the packages active. gWLM will automatically reduce the
resources available to the low-priority workloads to maintain performance objectives of the higher-
priority workloads. Alternatively, if the system has TiCAP resources available, you could leave low-
priority packages as they are and let gWLM activate the additional TiCAP resources only if needed
to achieve the workload’s policy.