Assigning a Cell to a Partition

A cell can be assigned to a partition only if sufficient cell usage rights are available across the complex, as well as sufficient memory usage rights to enable activation of all the memory on the cell, and sufficient usage rights for at least one core of the cell to be active.

In an Instant Capacity system, when a cell is assigned to a partition, depending on the number of core usage rights available in the system when the cell is assigned, the number of intended active cores for the partition automatically changes. Figure 4-2, Figure 4-3, and Figure 4-4illustrate a single partition with one assigned and one unassigned cell.

Figure 4-2 Partition premodification state: One cell assigned with 3 active and 1 inactive cores, and usage rights for 2 additional cores

Cell 1

Available Core

Usage Rights

 

A A A I

UR

UR

A Active Core

I Inactive (iCAP) Core

Figure 4-3 Premodification state: Unassigned cell with 4 inactive cores and no usage rights

Cell 2

I I I I

Figure 4-4 Partition postmodification state: Cell 2 assigned to partition

Cell 1

Cell 2

A A A I

A A I I

When Cell 2 is assigned to the partition, the number of intended active cores for the partition is automatically changed to 5. When the partition is rebooted, 5 cores in the partition are activated.

When an unassigned cell is assigned to a partition via the parmodify command, the Instant Capacity software determines the number of available core usage rights in the complex, and uses this number to activate as many cores as possible in the new cell. (This number typically corresponds to the icapstatus value for Additional cores that can be activated with current usage rights or the actual number of cores, whichever is smaller. In order to assign an inactive cell to a partition, this value must be nonzero.)

However, when a new partition is created via the parcreate command, core usage rights must be available for all cores configured on the new partition's cells, and core usage rights are automatically assigned to these new cells. For more information see “New Partition Creation and Instant Capacity” (page 196).

Note that when determining available usage rights, the Instant Capacity software calculates the usage rights consumed by each partition to be the greater of either the actual active or intended active cores for the partition.

Assigning a Cell to a Partition

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