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Important: Level 1 capacity resolution: When allocating additional processor capacity in
excess of the entitled pool capacity of the Shared Processor Pool, the POWER Hypervisor
takes the uncapped weights of all micro-partitions in the system into account, regardless
of the multiple Shared Processor Pool structure.
Where there is unused processor capacity in under-utilized Shared Processor Pools,
the micro-partitions within the Shared Processor Pools cede the capacity to the
POWER Hypervisor.
In busy Shared Processor Pools, where the micro-partitions have used all of the entitled pool
capacity, the POWER Hypervisor allocates additional cycles to micro-partitions, in which all
of these statements are true:
► The maximum pool capacity of the Shared Processor Pool hosting the micro-partition has
not been met.
► The micro-partition is uncapped.
► The micro-partition has enough virtual-processors to take advantage of the
additional capacity.
Under these circumstances, the POWER Hypervisor allocates additional processor capacity
to micro-partitions on the basis of their uncapped weights independent of the Shared
Processor Pool hosting the micro-partitions. This can be referred to as Level 1 capacity
resolution. Consequently, when allocating additional processor capacity in excess of the
entitled pool capacity of the Shared Processor Pools, the POWER Hypervisor takes the
uncapped weights of all micro-partitions in the system into account, regardless of the Multiple
Shared Processor Pools structure.
Dynamic adjustment of maximum pool capacity
The maximum pool capacity of a Shared Processor Pool, other than the default Shared
Processor Pool 0 , can be adjusted dynamically from the managed console, using either the
graphical or command-line interface (CLI).
Dynamic adjustment of Reserve Pool Capacity
The reserved pool capacity of a Shared Processor Pool, other than the default Shared
Processor Pool 0 , can be adjusted dynamically from the managed console, using either the
graphical or CLI interface.
Dynamic movement between Shared Processor Pools
A micro-partition can be moved dynamically from one Shared Processor Pool to another
using the managed console using either the graphical or CLI interface. Because the entitled
pool capacity is partly made up of the sum of the entitled capacities of the micro-partitions,
removing a micro-partition from a Shared Processor Pool reduces the entitled pool capacity
for that Shared Processor Pool. Similarly, the entitled pool capacity of the Shared Processor
Pool that the micro-partition joins will increase.
Deleting a Shared Processor Pool
Shared Processor Pools cannot be deleted from the system. However, they are deactivated
by setting the maximum pool capacity and the reserved pool capacity to zero. The Shared
Processor Pool will still exist but will not be active. Use the managed console interface to
deactivate a Shared Processor Pool. A Shared Processor Pool cannot be deactivated unless
all micro-partitions hosted by the Shared Processor Pool have been removed.
118 IBM Power 720 and 740 Technical Overview and Introduction