HP Integrity Essentials Global Workload Manager: Workload Management for HP Integrity Virtual Machines

6
• When managing virtual machine workloads, if Instant Capacity is available and gWLM needs to
deactivate cores on the VM Host to make more resources available elsewhere, gWLM always
maintains the minimum number of cores required for the VM Host’s virtual machines. For example,
if a virtual machine has three vCPUs, gWLM will ensure that the minimum of three cores is
maintained for that virtual machine. A virtual machine must have a core available for each
configured vCPU. For an example, see “Scenario 4: gWLM Maintains Virtual Machine Minimum
vCPU When Resources Are Needed Elsewhere” on page 15.
• When using gWLM with VSE to create an SRD, a workload named by default hostname.OTHER will
be displayed, where hostname is the name of the system serving as the VM Host. This is the
workload where gWLM places unassigned resources. You cannot remove this workload, although
you can change its name from the default. This workload consists of all CPU resources consumed by
processes running on the VM Host. For information, see “How Virtual Machine Entitlements Map to
gWLM Policies” on page 7.
• You can determine whether a virtual machine is being controlled by gWLM by using either of the
following methods:
• Under VSE, on the System tab, select the “VM Host” link. In the resulting screen, see
the “External Manager” entry.
• Run the command hpvmstatus –S on the VM Host
• When controlling HP VM resources, gWLM allows you to use Integrity VM Manager and standard
Integrity VM commands. However, while the virtual machine is running in a deployed SRD, gWLM
prevents you from modifying its dynamically determined entitlement.
• While a virtual machine is running in a deployed SRD, do not change the number of configured
vCPUs. To have gWLM recognize a vCPU configuration change, first undeploy and delete the
existing SRD, then change the virtual machine’s configuration and restart the virtual machine. Once
the virtual machine has started, create a new SRD to contain that virtual machine workload.
• You can power a virtual machine on or off from the EFI console prompt while it is associated with a
workload in a deployed SRD.
• If you want to stop managing a virtual machine with gWLM (removing the associated workload
from the SRD), you must stop the virtual machine first. When gWLM stops managing a virtual
machine, it sets the dynamic entitlement of the running virtual machine to 5% (by default) to ensure
that it can be started when the SRD is undeployed. Once a virtual machine workload is removed
from the SRD, the virtual machine is prevented from starting and from consuming VM Host
resources; it will be allowed to start and consume VM Host resources once the SRD is undeployed.
gWLM Policies You Can Establish for Virtual Machine
Workloads
gWLM provides several types of policies. This section describes the OwnBorrow policy. The
OwnBorrow policy allows you to set the following values, which are expressed as percentages:
• The owned amount of CPU resources—the virtual machine is provided the owned amount when
needed.
• The minimum amount of CPU resources a virtual machine should always have after lending
unneeded resources—when the virtual machine is not busy, it can lend up to a designated amount
to other machines; if the machine becomes busy again, it can reacquire the lent-out resources
immediately up to its owned amount.