chapter  15

Super Servers — One Step Beyond

WithA. Padgett Peterson

Occasionally, advances developed for Super Servers technology will become standard, such as RAID. More often the technology will be obviated by advances in another area with the risk that the unit will become unmaintainable. Enhanced Small Device Interface (ESDI) appeared to have such promise and was widely used for servers, since considerably higher throughput was available than for standard ST-506 drives. However, technology leapfrogged directly to IDE, which was a logical extension of the ESDI concept, leaving ESDI in a backwater. Some elements have been staples of super servers: the first and most common element is RAID disk storage, usually providing very high burst throughput. Symmetric multiprocessing (SMP) is another staple of super server technology. Again the promise is generally increased throughput through task designation. In a truly high-end system, both mirroring and SMP may be found in a single unit, with multiple peripheral busses and RAID disk farms, extending the RAID philosophy to every element of the server.