HP-UX Virtual Partitions Administrator Guide (includes A.05.08) (5900-1312, March 2011)

CPU
NOTE:
Processor Terminology
Processing resources under vPars, both as input arguments and command outputs, are described
as “CPUs.” For multi-core processors such as the PA-8800, the term “CPU” is synonymous with
“core.” The term “processor” refers to the hardware component that plugs into a processor socket.
Therefore a single processor can have more than one core, and vPars commands will refer to the
separate cores as distinct “CPUs,” each with its own hardware path.
Two vPars terms pre-date multi-core processors, so they are exceptions to this terminology:
• “boot processor,” which refers to the CPU (that is, core) on which the OS kernel of the virtual
partition was booted, and
• “cell local processor (CLP),” which refers to a CPU on a specified cell.
For more information on dual-core processors, see “CPU: Dual-Core Processors” (page 243).
CPU migration refers to adding CPUs to and deleting CPUs from a virtual partition. Dynamic CPU
migration refers to migrating CPUs while the target virtual partition is running. vPars allows the
assignment of most CPUs while the virtual partitions are running.
For vPars A.03 and earlier, the two types of CPUs are bound and unbound (floater) CPUs. This
discussion begins at “CPU: Bound and Unbound” (page 239).
NOTE:
Using vPars A.03.xx and Earlier Syntax on a vPars A.04.xx System
Although not recommended under most circumstances, you can still use the vPars A.03.xx CPU
syntax on vPars A.04.xx systems. However, the concepts and rules of boot processors and dynamic
CPUs in A.04.xx will apply because the concepts and rules of bound and unbound CPUs in A.03.xx
no longer apply.
CPU: Specifying Min and Max Limits
The syntax to specify min and max CPUs assigned to a virtual partition is:
-[a|m] cpu:::[min][:max]
where:
-a is adding (used with vparcreate or vparmodify)
-m is modifying (used with vparmodify)
min is the minimum number of CPUs for the virtual partition to boot and the minimum number
of CPUs that must remain assigned to the partition
max is the maximum number of CPUs that can be assigned to the virtual partition
NOTE: The virtual partition must be in the down state to set the min or max value.
The total count of CPUs in the virtual partition must always be greater than or equal to min and
less than or equal to max.
Examples
• To set the minimum number of CPUs to 2:
keira1# vparmodify -p keira2 -m cpu:::2
• To set the minimum number of CPUs to 2 and the maximum to 4:
keira1# vparmodify -p keira2 -m cpu:::2:4
238 CPU, Memory, and I/O Resources (A.03.xx)