HP-UX Virtual Partitions Administrator Guide (includes A.05.07) (5900-1229, September 2010)

CPU: Adding, Removing, and Migrating Unbound CPUs
For vPars A.03.xx and earlier, after min bound CPUs are assigned to a virtual partition, the
quantity (total - min) CPUs are assigned to the partition as unbound CPUs. Therefore, to
migrate unbound CPUs, specify total such that (total-min) is the number of unbound CPUs
assigned to the target partition.
Examples
• To create the partition winona2 with two bound CPUs and one unbound CPU, set total
to three and min to two (vPars A.03.xx and earlier):
# vparcreate -p winona2 -a cpu::3 -a cpu:::2
• To add an unbound CPU to an existing partition, use the vparmodify command to either
modify the total number of CPUs (-m cpu::total) or add to the total number of
CPUs (-a cpu::total).
For example, to add one unbound CPU to the partition winona2, which already has three
CPUs, two of which are bound, you can either modify total to four:
winona1# vparmodify -p winona2 -m cpu::4
or add one to total:
winona1# vparmodify -p winona2 -a cpu::1
• To delete one unbound CPU from the partition winona2, which already has four CPUs:
winona1# vparmodify -p winona2 -m cpu::3
or
winona1# vparmodify -p winona2 -d cpu::1
• Because you can dynamically migrate unbound CPUs, you can migrate an unbound CPU
from one partition to another while both partitions are running. For example, if the partition
winona1 has two bound CPUs and the partition winona2 has two bound and two unbound
CPUs, you can migrate an unbound CPU from winona2 to winona1 using the following:
winona1# vparmodify -p winona2 -d cpu::1
winona1# vparmodify -p winona1 -a cpu::1
NOTE: Migrating unbound CPUs may not fully complete immediately after executing the
vparmodify commands.
For more information on CPUs, see the following:
• For information on bound and unbound CPUs, see “CPU: Bound and Unbound” (page 259).
If you do not know which CPUs are bound CPUs and which are unbound CPUs, use the
vparstatus command. See “Commands: Displaying vPars Monitor and Resource
Information (vparstatus)” (page 141) and the vparstatus(1M) manpage.
• For issues with using vparmodify, see the vparmodify(1M) manpage.
For required partition states, see the vparresources(5) manpage.
CPU: Managing I/O Interrupts
This section describes information you need if you are managing I/O interrupts on a vPars-enabled
system. Note that migrating interrupts should only be done by advanced administrators for
performance tuning.
CPU: Adding, Removing, and Migrating Unbound CPUs 263