HP-UX Virtual Partitions Administrator's Guide (includes A.03.05 and A.04.05)

NOTE: The target virtual partition can be up or down when specifying by hardware path.
CPUs that are added using the hardware path syntax can be deleted only by using the hardware
path syntax.
Adding or deleting CPUs by hardware path changes total only when the virtual partition is up
(unless the operation is an addition and the specified CPU is already assigned to the partition).
If the virtual partition is down, total is not changed and becomes a high boundary. For example,
if keira2 is down and total is set to 2, you cannot have more than 2 CPUs added by hardware
path. This is for A.03.xx-backwards compatibility.
Example
• To add the CPUs at 0/10 and 0/11 to keira2:
keira1# vparmodify -p keira2 -a cpu:0/10 -a cpu:0/11
Using both the Hardware Path Specification and CLP specification
Although you can add and delete CPUs by hardware path, to avoid confusion it is recommended
that you specify by cell rather than by hardware path. The exception is for dual-CPU sockets.
For dual-CPU sockets, if you wish to have both CPUs of a socket assigned to the same virtual
partition, you should specify by hardware path instead of by cell. Specifying by cell cannot
guarantee that both CPUs in the socket are the CPUs chosen by the Monitor and assigned to the
target virtual partition., although the Monitor will attempt to do this whenever possible.
For more information on dual-core CPU usage, see “CPU: Dual-Core Processors” (page 234).
CPU: Syntax, Rules, and Notes
vparstatus
• When a virtual partition is down, vparstatus does not show any CPU assigned as the
boot processor. The boot processor is not assigned until the virtual partition is actually
booted.
• If a virtual partition is down and assigned only one CPU, a CPU will be reserved by the
vPars Monitor, making it unavailable. The specific CPU reserved is not determined until
boot time. As a result, while the virtual partition is down, vparstatus -A, which shows
available resources, will show all the possible paths of unassigned CPUs but the count of
available CPUs will be one less. The count reflects the actual number of available CPUs
because one CPU is reserved for the down virtual partition.
Counts Summary
• At all times, the rule of min<=total<=max is enforced.
• When adding by CLP, the total count changes whether the partition is up or down.
• When adding by hardware path, the total count changes only when the partition is up. The
total does not change if the specified CPU is already assigned to the partition.
• When adding by hardware path and the partition is down, you cannot have the number of
CPUs added by hardware path exceed the current total value.
CPU: Syntax, Rules, and Notes 231