On Thu, Oct 15, 2009 at 12:50:48PM +0100, Richard Miller wrote: > > It's easy to write good code that will take advantage of arbitrarily many > > processors to run faster / smoother, if you have a proper language for the > > task. > > ... and if you can find a way around Amdahl's law (qv).
"The speedup of a program using multiple processors in parallel computing is limited by the time needed for the sequential fraction of the program." So it would only be a problem supposing that a significant part of the program is unparallelizable. I can think of many many tasks where "Amdahl's law" is not going to be a problem at all, for a properly designed system. For example if I had a thousand processors I might raytrace complex scenes for an animated game at 100 fps, or do complex dsp over a 2 hour audio track in one millisecond. I suppose most difficult/interesting tasks can be parallelized effectively. Seems that Amdahl's law is a minor issue. Of course if you are trying to run old-fashioned sequential programs on a parallel machine you will not benefit. You would need to rewrite them. Sam
