IBM Power 770, Technical Overview And Introduction

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Chapter 3. Virtualization
137
Default shared processor pool (SPP
0
)
On any Power Systems server supporting multiple shared processor pools, a default shared
processor pool is always automatically defined. The default shared processor pool has a pool
identifier of zero (SPP-ID = 0) and can also be referred to as SPP
0
. The default shared
processor pool has the same attributes as a user-defined shared processor pool except that
these attributes are not directly under the control of the system administrator. They have fixed
values (Table 3-4).
Table 3-4 Attribute values for the default shared processor pool (SPP
0
)
Creating Multiple shared processor pools
The default shared processor pool (SPP
0
) is automatically activated by the system and is
always present.
All other shared processor pools exist, but by default are inactive. By changing the maximum
pool capacity of a shared processor pool to a value greater than zero, it becomes active and
can accept micropartitions (either transferred from SPP
0
or newly created).
Levels of processor capacity resolution
The following two levels of processor capacity resolution are implemented by the POWER
Hypervisor and Multiple shared processor pools:
򐂰 Level
0
The first level, Level
0
, is the resolution of capacity within the same shared processor pool.
Unused processor cycles from within a shared processor pool are harvested and then
redistributed to any eligible micropartition within the same shared processor pool.
򐂰 Level
1
This is the second level of processor capacity resolution. When all Level
0
capacity has
been resolved within the multiple shared processor pools, the POWER Hypervisor
harvests unused processor cycles and redistributes them to eligible micropartitions
regardless of the Multiple shared processor pools structure.
SPP
0
attribute Value
Shared processor pool ID 0
Maximum pool capacity The value is equal to the capacity in the physical shared
processor pool.
Reserved pool capacity 0
Entitled pool capacity Sum (total) of the entitled capacities of the micropartitions in the
default shared processor pool.