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Grid Computing at a Glance
An anonymous reader writes "Grid computing is the "next big thing," and this article's goal is to provide a "10,000-foot view" of key concepts. This article relates many Grid computing concepts to known quantities for developers, such as object-oriented programming, XML, and Web services. The author offers a reading list of white papers, articles, and books where you can find out more about Grid computing."
As we discovered early on in MIMD parallel computing, MIMD (aka grid computing) parallelism can only really help processes that are CPU bound in the first place.
Most of the processes that require 'big iron' are memory bound and I/O bound--e.g. databases that are hundreds of gigabytes to terabytes in size. This is why so many CPUs are '90% idle' in the first place, and this is why system designers devote more attention to bit-striping their disks, a good RAID controller, bus speeds, disk seek time and so forth.
Problems that require brute-force computation on small amounts of data, and produce small results, are simply few and far between -- and the people addressing those problems have been onto MIMD for decades. For instance, my first publication, in 1987 to the USENIX UNIX on Supercomputers proceedings, involved putting ODE solvers wrapped in Sun RPC, so that hundreds of servers could work on a different part of initial condition and boundary condition space, to provide a complete picture of the properties of certain nonlinear ordinary differential equations. Cryptanalysis and protein folding problems are already being addressed in a similar manner, and the tools to distribute these services as well as the required communications standards have been around for more than a decade.
Furthermore, if you've already got a marginally communications-bound domain decomposition of a parallel problem, and you want to cut down the communications overhead in order to take advantage of MIMD parallelism, the last communications protocol you're going to use is a high-overhead one such as CORBA, or a text-based message protocol such as XML. Both XDR and MPI are faster, more stable and better established in the scientific computing community than Yet Another layer of MIMD middleware--which is all Grid Computing is.