Patent attributes
A partition migration mechanism migrates a logical partition executing an operating system and resumes the logical partition before all resources in the logical partition have been migrated. When a partition is being migrated, a call checkpoint mechanism creates checkpoints of the state of the operating system when the partition manager is called. Before performing the call to the partition manager, a check is made to determine if all resources required by the call are available. If so, the partition manager call is executed. If all resources required by the call are not available, a resource fault is indicated, which causes the operating system state from the last checkpoint to be restored and a corresponding virtual CPU to be preempted until the resource that caused the fault becomes available. Exceptions that do not require the missing resource may be performed while the virtual CPU awaits the resource to become available.