You can use the vxtask command to administer operations on VxVM tasks that are running on the system. Operations include listing tasks, modifying the state of a task (pausing, resuming, aborting) and modifying the rate of progress of a task.
VxVM tasks represent long-term operations in progress on the system. Every task gives information on the time the operation started, the size and progress of the operation, and the state and rate of progress of the operation. The administrator can change the state of a task, giving coarse-grained control over the progress of the operation. For those operations that support it, the rate of progress of the task can be changed, giving more fine-grained control over the task.