4.2. Dynamic Load Balancing with DM-Multipath
Device Mapper Multipathing (DM-Multipath) creates a single conceptual device from the multiple cables, switches and controllers that connect servers to storage arrays. This enables centralized management of connection devices (also known as paths) and makes it possible to balance loads over all available paths.
DM-Multipath in Red Hat Enterprise Linux 6 introduces two new options when dynamically balancing load over paths. Paths can now be dynamically selected depending on either the queue size of each path or previous I/O time data.