Advanced POWER Virtualization on IBM System p5 - Previous ...

processor pool in systems with APV), permanent activated CUoD processors, or
temporary activated On/Off processors.
For more information about processors on demand On/Off, refer to 2.4.3,
“Capacity Upgrade on Demand” on page 40.
Processors in the shared processor pool
All the processors that become active and non-dedicated are part of the shared
processor pool; thus, the quantity of processors in the shared processor pool
equals the quantity of active non-dedicated processors in the system.
Entitled capacity for micro-partitions
The entitled capacity is the real capacity in terms of computing power that a
partition is given even when it starts up or by executing dynamic LPAR operations
when running. The entitled capacity applies only at runtime and is the
guaranteed amount of processing units a micro-partition can consume. There are
two ways to define a shared processor partition: capped and uncapped mode.
For a capped micro-partition, the entitled capacity is also the maximum
processing power the partition can use and its first value was given at start up.
Keep in mind that with dynamic LPAR operations, it is possible to add processing
units to the entitled capacity depending on both system resources in the shared
processor pool and the maximum quantity of processing units allowed for the
partition.
For an uncapped micro-partition, the entitlement capacity given to the partition is
not limiting the access to processing power. An uncapped micro-partition can use
more than the entitled capacity when there are free resources in the shared
processor pool. The limiting factor for uncapped micro-partition is the number of
defined virtual processors. The micro-partition can use as many as there are
physical processors in the shared processor pool, since each virtual processor is
dispatched to a physical processor at a time.
Virtual processors for micro-partitions
The virtual processors are created for the operating systems of micro-partitions
to enable the mechanism that shares physical processors in the shared
processing pool between such micro-partitions. The operating system in a
micro-partition handles virtual processors as discrete entities (system objects)
and the hardware dispatches the virtual processors to physical processors in a
time-share basis.
Chapter 2. <strong>Virtualization</strong> technologies on System p servers 57