HP Instant Capacity User's Guide for Versions 8.x
NOTE: Instant Capacity will always consume unused capacity before it consumes additional
usage rights when activating cores. Instant Capacity will always release usage rights from unused
capacity before it releases usage rights by deactivating cores.
Constraints
The Instant Capacity software will not activate a core that is marked for deconfiguration. Also,
you cannot use Instant Capacity to activate more cores than are configured in the current
nPartition. If you want more, you need to modify the nPartition with the parmodify command.
You can use Instant Capacity to activate more cores than are configured into the current virtual
partition, but only if the associated nPartition contains enough unassigned cores to fulfill the
request. Otherwise, you need to use parmodify to reconfigure the nPartitions, or vparmodify
to remove cores from other virtual partitions within the same nPartition (essentially, adding to
the unassigned pool).
Instant Capacity Activation Example Session
The following example shows you how to activate an additional core. At the beginning of this
activation session, there are a total of 4 cores in the partition; 2 cores are activated and 2 are
inactive, but usage rights have been acquired to activate at least one inactive core. In this example,
1 additional core is activated, leaving the partition with 3 active cores and 1 inactive core:
Example 4-3 Activating an Additional Core (HP-UX)
> /usr/sbin/icapmodify -a 1 "Add CPU for new FY: Bill P."
3 cores are intended to be active and are currently active.
Points of interest in the above activation example are:
• The core activation is instant (that is, a reboot is not required).
• The double-quoted text serves as an audit trail of why the activation was done and who
performed it. This information is optional and is written to the Instant Capacity log file
(var/adm/icap.log) if provided.
NOTE: To defer the activation until the next reboot, add the -D option to the command. See
the HP-UX manpage icapmodify(1M) for details.
The icapmodify command allows you to activate additional cores with the -a option, or set
the total number of active cores with the -s option. For example, the icapmodify
command/option -a 2 activates two additional cores in a partition. The icapmodify
command/option -s 2 sets the total number of active cores in a partition to 2.
See “Software Application Considerations” (page 69) for details of software application
implications when activating additional cores.
60 Using Instant Capacity to Manage Processing Capacity