Concepts and Terms for Using gWLM

The collection of processes that are within a single compartment. The compartment can be an nPartition (npar), a virtual partition (vpar), a virtual machine provided by HP Integrity Virtual Machines (hpvm), a processor set (pset), or a Fair Share Scheduler (fss) group. gWLM manages a workload by adjusting the system resource allocations for its compartment. (For background information on npars, vpars, virtual machines, psets, and fss groups, refer to the section “The gWLM Management Model”.)

An npar, a vpar, a virtual machine, a pset, or an fss group with its resource allocation being managed by gWLM.

Multiple compartments are grouped to form a shared resource domain, or SRD. The compartments all share the resources within the SRD. Each compartment holds a workload and can be in only one deployed SRD. gWLM manages each workload by adjusting the resource allocation for its compartment.

A collection of compartments that can share system resources. The compartments can be npars, vpars, virtual machines, psets, or fss groups. For example, a server containing npars can be an SRD—as long as the requirements in the section “The gWLM Management Model” are met. Also, a server or an npar divided into vpars can be an SRD for its vpar compartments. Similarly, a server or an npar divided into virtual machines can be an SRD for its virtual machine compartments.

gWLM allows you to nest compartments. gWLM then manages resources for the various levels of compartments.

A collection of settings that instruct gWLM how to manage a workload’s resources. For example, a policy can indicate the amount of CPU resources a workload owns (and is allocated when needed) as well as how much of those resources the workload can lend to other workloads.

A single policy can be associated with, or applied to, multiple workloads.

Two modes are available: advisory and managed. Advisory mode allows you to see what CPU resource requests gWLM would make for a workload—without actually affecting resource allocation.

Advisory mode is not available for SRDs containing virtual machines, psets, or fss groups.

You can use this mode when creating and fine-tuning your policies. Once you are comfortable with your policies, use managed mode to have gWLM automatically adjust the resource allocations for your defined workloads.

You can only set the mode on the SRD level: All workloads within an SRD operate in the same mode, either advisory or managed.

Enable gWLM control of an SRD.

Deploying an SRD in managed mode enables gWLM control of resource allocation within the SRD. For example, in an SRD based on a vpar that has psets for compartments, deploying an SRD in managed mode allows gWLM to actively migrate cores among psets. (A core is the actual data-processing engine within a processor. A single processor might have multiple cores.)

When deploying an SRD in advisory mode, gWLM simply reports what the allocation would be—without actually affecting resource allocations on a system.

Advisory mode is not available for SRDs containing virtual machines, psets, or fss groups.

Disable gWLM’s management of resources in a specified SRD.

If an SRD is in managed mode, undeploying stops the migration of system resources among workloads in the SRD. If the SRD is in advisory mode, gWLM no longer provides information on what requests would have been made.