Logical Partitions - Dedicated Processors
The following scenario explains how a powered-off partition using dedicated processors makes its processors available in a shared processor pool.
Server firmware is the code that resides in system flash memory. Server firmware includes a number of subcomponents, one of them being the logical partition firmware.
The shared processor pool is a group of physical processors that provide processing capacity that can be shared among multiple logical partitions.
In this example we have three logical partitions on the server.
Dedicated processors are whole processors that are assigned to a single partition. If you assign dedicated processors to a logical partition, you must assign a whole number of processors to that partition.
In this example, partition 1 has one dedicated processor. Partition 1 is utilizing 99% of its assigned resource.
Partitions 2 and 3 have been assigned 0.50 processing units each and are using only 50% of their assigned resources (0.25 processing units each).
Partition 2 and 3 now have more activity and are using all of their assigned resources.
A powered-off partition using dedicated processors will have its processors available to the shared processing pool. In this example, partition 1 has been powered down.
The unused processor is now available to the shared processor pool.
Partition 2 and 3 are running at 100% utilization and need more processing power.
The processors in the shared processing pool are used by partitions 2 and 3 to ensure tasks are being processed.
If the dedicated partition is powered on again, the assigned processor resource will be returned. In this example all of the assigned resource dedicated to partition 1 is returned.