HP Instant Capacity User's Guide for Version 9.x

4.9 Activations and Deactivations in a Virtual Partition Environment
Instant Capacity can be present on HP-UX systems or partitions where virtual partition technology
is employed. In a virtual partition environment, cores that are not assigned to any virtual partition
are considered inactive (in addition to other classes of inactive cores). Unassigned cores can be
assigned (activated) or deassigned (deactivated) using either the icapmodify command or the
vparmodify command, depending on the type of adjustment needed and the level of logging
or reporting desired.
One important consideration is that vparmodify can be used to activate or deactivate cores in
other virtual partitions within the nPartition; icapmodify only activates or deactivates cores
within the current virtual partition (the partition where the command is invoked). The
vparmodify command does not change the value for the number of intended active cores for
the nPartition.
Another consideration is that core assignment via the vparmodify command does not result
in Instant Capacity logging of the activation, email configuration change notification, or
transmission of an asset report to HP.
NOTE: Deferred activations and deactivations are not supported in any virtual partition
environment.
Instant Capacity always consumes unused capacity before it consumes additional usage rights
when activating cores. Instant Capacity always releases usage rights from unused capacity before
it releases usage rights by deactivating cores.
4.9.1 When to Use the vparmodify or icapmodify Commands
When usage rights freed by deactivating cores are to be used in a different nPartition, use the
icapmodify command. When usage rights freed by deactivating cores are to be used by another
virtual partition within the same nPartition, use the vparmodify command. The following
sections provide details on activating and deactivating cores within nPartition and virtual partition
environments.
4.9.2 What is Unused Capacity
In a virtual partition environment, the Instant Capacity software may allocate or deallocate cores
from what is called “unused capacity”. Unused capacity is the difference between actual active
and intended active cores, and it is a side effect of using vparmodify to deactivate cores while
not immediately activating the cores in another virtual partition within the same nPartition. This
is usually a transient state, since a user typically migrates cores from one virtual partition to
another with a deactivate command followed by an activate command. However, unused capacity
can persist if, for example, a utility such as gWLM ignores an error status from an activation and
leaves the previously deactivated cores in an unassigned state. The Instant Capacity software
always takes unused capacity into account when a request is made to activate or deactivate cores
such that it attempts to eliminate the discrepancy between intended active and actual active.
4.9.3 Static Virtual Partitions
If a virtual partition is static (that is, if its resources cannot be migrated, added, deleted, or
modified) and you attempt to activate or deactivate cores, the Instant Capacity software displays
a message indicating that the configuration cannot be modified.
62 Using Instant Capacity to Manage Processing Capacity