Chapter 3. Virtualization
139
Where there is unused processor capacity in under-utilized shared processor pools,
the micropartitions within the shared processor pools cede the capacity to the
POWER Hypervisor.
In busy shared processor pools, where the micropartitions have used all of the entitled pool
capacity, the POWER Hypervisor allocates additional cycles to micropartitions, in which
all
of
the following statements are true:
The maximum pool capacity of the shared processor pool hosting the micropartition is not
met.
The micropartition is uncapped.
The micropartition has enough virtual-processors to take advantage of the
additional capacity.
Under these circumstances, the POWER Hypervisor allocates additional processor capacity
to micropartitions on the basis of their uncapped weights independent of the shared
processor pool hosting the micropartitions. 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 micropartitions in the system into account, regardless of the multiple
shared processor pool 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 interface or the command-line interface (CLI).
Dynamic adjustment of reserved 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, by using either the
graphical interface or the CLI.
Dynamic movement between shared processor pools
A micropartition can be moved dynamically from one shared processor pool to another using
the managed console using either the graphical interface or the CLI. Because the entitled
pool capacity is partly made up of the sum of the entitled capacities of the micropartitions,
removing a micropartition 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 micropartition 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
micropartitions hosted by the shared processor pool have been removed.
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 micropartitions in the system
into account,
regardless of the
Multiple shared processor pool structure
.
Summary of Contents for Power 780
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