PVMe supports PVM, but its internal structure is completely new. As it runs on a PVMe homogeneous platform (The IBM 9076 SP2), many operations are simpler.

The following are the outstanding differences between the structure of the PVM and IBM AIX PVMe.

• PVMe does not interact directly with TCP/IP to implement data communication between processors. For this,it uses the System Communication (CSS), communications software that runs on the HPS adapter. Data exchange always occurs between processes, without involving the devil.
• The PVMe daemon runs in a single node and not all participating nodes as PVM.
• An improved scheme for memory management of PVMe can also take advantage of memory resources efficiently.

The above were the main differences between PVM & IBM AIX PVMe that I can come up with. Please put a comment of other important difference that I had missed.