Successes

The VI Architecture has largely achieved its goals. Hardware vendors have developed a number of VI-compliant products that feature high bandwidth coupled with low overhead. Implemented on a variety of network media, these products have clearly demonstrated the portability and network independence of VI. The successful integration of VI with several operating systems has shown that the technology is OS independent as well.

Significant commercial applications have been developed using VI directly. These show that VI can be used to increase the scalability of parallel and distributed applications.

In addition, legacy message-passing interfaces have been implemented on top of VI. These include MPI for high-performance, parallel computing, and Sockets for commercial applications.

By standardizing the hardware layer, the wire protocols, and other system elements, InfiniBand has further extended the benefits of the VI Architecture.

The VI Architecture has also influenced networked storage protocols. DAFS (discussed in Chapter 7) uses VI to bypass the operating system when performing file I/O. VI s RDMA concept has made its way into the iSCSI specification, where it will help improve performance by reducing data copies.

Areas for Improvement

There are several areas with which users and developers of the VI Architecture find fault. There are also a number of suggestions for VI extensions and refinements. The major areas are:

• Limited number of VIs

• Connection orientation

• Memory Registration

• Receive assumption, lack of...