HP Instant Capacity (iCAP) manual Activating Cores in a Virtual Partition Environment

NOTE: The icapstatus command output indicates that the number of cores that can be assigned (to the local virtual partition) is zero if the static resource attribute for the local virtual partition is set.

Activating Cores in a Virtual Partition Environment

In a virtual partition environment, the icapmodify command must be used to modify processing capacity when you are making any adjustment to an nPartition or to multiple nPartitions. When you execute the icapmodify command to activate a core, the Instant Capacity software verifies that the request can be satisfied. If so, the local nPartition’s intended active number is increased, and the appropriate number of cores are added to the local virtual partition.

When cores in a virtual partition are activated using the icapmodify command, if unused capacity is available, the cores are activated from the unused capacity balance before increasing the active cores. If enough cores are available to meet the request, the proper number of cores are added to the local virtual partition. If there is any unused capacity available prior to the activation, the result is that the actual active count changes by more than the intended active count, and the intended active count may not change at all. However, the discrepancy between intended active and actual active is reduced. If there is no unused capacity available, the desired number of cores will be activated in the virtual partition.

If you are adjusting core assignments across virtual partitions in a single nPartition, use the vparmodify command for the best coordination between the Instant Capacity software and the vPars software, and for optimized performance. The vparmodify command is the fastest and most efficient way to adjust capacity within virtual partitions of a single nPartition, but it does not affect the intended active count for the nPartition. Therefore, it cannot be used to migrate unused capacity either to or from other nPartitions. When you execute the vparmodify command to activate a core, the command verifies with the Instant Capacity software how many cores are available for activation. This number is calculated as the difference between the local nPartition’s intended active number and the total number of cores assigned to the vPars database.

Deactivating Cores in a Virtual Partition Environment

In a virtual partition environment, the icapmodify command must be used to modify processing capacity when you are making any adjustment to an nPartition or to multiple nPartitions. When you execute the icapmodify command to deactivate a core, the Instant Capacity software verifies that the request can be satisfied. If so, the local nPartition’s intended active number is decreased, and the appropriate number of cores are removed from the local virtual partition.

When the icapmodify command is used in a virtual partition, it checks with the Instant Capacity software to determine how many cores are available for deactivation. This number is calculated as the difference between the local nPartition’s intended active number and the total number of cores assigned to the vPars database. If there is any unused capacity available prior to the deactivation, the result is that the actual active count changes by more than the intended active count, and the intended active count may not change at all. However, the discrepancy between intended active and actual active is reduced.

If you are adjusting core assignments across virtual partitions in a single nPartition, use the vparmodify command for the best coordination between the Instant Capacity software and the vPars software, and for optimized performance. The vparmodify command is the fastest and most efficient way to adjust capacity within virtual partitions of a single nPartition, but it does not affect the intended active count for the nPartition and it therefore cannot be used to migrate unused capacity either to or from other nPartitions. When you execute the vparmodify command to deactivate a core, authorization is not required from the Instant Capacity software.

Whether you are activating or deactivating cores, the icapmodify command adjusts only the number of dynamic cores, and it does not explicitly identify specific cores.

Activations and Deactivations in a Virtual Partition Environment 65