Alan M. Webb IBM Research Division, Thomas J. Watson Research Center, P.O. Box 704, Yorktown Heights, New York 10598 (alan_webbus.ibm.com). Mr. Webb is a Senior Software Engineer who joined IBM UK in 1977. He received an M.S. degree with distinction in software engineering from Oxford University in 1997. Mr. Webb has worked as a developer and architect in Hursley, England, and in Raleigh, North Carolina. In 1999, he joined the IBM Thomas J. Watson Research Center, where he has worked on various projects related to IBM server software technologies.

Ray Mansell IBM Research Division, Thomas J. Watson Research Center, P.O. Box 704, Yorktown Heights, New York 10598 (mansellus.ibm.com). Mr. Mansell joined the IBM UK Laboratories in 1974 after receiving a bachelor's degree in electronic engineering from the University of Bath. He joined the IBM Thomas J. Watson Research Center in 1990 and has worked on high-performance file systems, virtualization, and operating systems.

Joshua W. Knight IBM Research Division, Thomas J. Watson Research Center, P.O. Box 704, Yorktown Heights, New York 10598 (joshkus.ibm.com). Dr. Knight is a Research Staff Member. He received a B.S. degree in engineering physics from Cornell University in 1968 and a Ph.D. degree in applied physics from Stanford University in 1978. He joined IBM in 1981 and has since worked on hardware and software performance and on server software technologies.

Steven J. Greenspan IBM Systems and Technology Group, 2455 South Road, Poughkeepsie, New York 12601 (fletchus.ibm.com). Mr. Greenspan received his B.S. degree in computer science in 1982 from the City College of New York. That same year, he joined IBM in Poughkeepsie, New York, to work on development tools. Since 1987, he has worked on the design and development of System z operating systems.

David B. Emmes IBM Systems and Technology Group, 2455 South Road, Poughkeepsie, New York 12601 (emmesus.ibm.com). In 1974, Mr. Emmes received his B.A. degree in mathematics summa cum laude from Washington University in St. Louis. He received his M.S. degree in mathematics from M.I.T. in 1976, and his M.S. degree in computer and information science from Syracuse University in 1985. He joined IBM in 1978 and has designed and developed z/OS operating system support for real storage management, Sysplex communications, workload management, TCP/IP, and Java Virtual Machine performance enhancements. Since 2002, Mr. Emmes has been involved in the effort described in this paper, focusing on the QDIO driver and related hardware and firmware areas.