IBM V7000 Introduction And Implementation Manual page 474

If you want to migrate your volumes to another storage pool in one step instead of two, you
can use the Migrate to Another Pool option (Figure 10-9).
Figure 10-9 Using the Migrate to Another Pool option
Volume Mirror advantages over Migrate to Another Pool:
When you move data, Volume Mirror has always two copies of data.
With Volume Mirror, you can add a copy on a larger number of volumes.
You can stop Volume Mirror copies at any time, also if copies are not yet synchronized.
With the -syncrate parameter of the Volume Mirror chvdisk command, you can
establish the speed to write a copy from 2 to 64 MB/s.
454
IBM Flex System V7000 Storage Node Introduction and Implementation Guide