Slashdot Mirror
More Interest In Parallel Programming Outside the US?
simoniker writes "In a new weblog post on Dobbs Code Talk, Intel's James Reinders discusses the growth of concurrency in programming, suggesting that '...programming for multi-core is catching the imagination of programmers more in Japan, China, Russia, and India than in Europe and the United States.' He also comments: 'We see a significantly HIGHER interest in jumping on a parallelism from programmers with under 15 years experience, verses programmers with more than 15 years.' Any anecdotal evidence for or against from this community?"
Spoken like a completely ignorant child. How the hell do you think (if you even can) we older guys got into this business? We were tinkering with new things, using them when appropriate, before many of you were born, and the joy of new ideas hasn't worn off. The only difference is we don't do it quite so impulsively, just because it seems new.
For one thing, multiple homogeneous cores is NOT new (hetero- either, for that matter), just fitting them into the same die. I've used quad 68040 systems, where, due to the ability of the CPUs to exchange data between their copy-back caches, some frequently-used data items were NEVER written to memory, and on System V you could couple processing as tightly or loosely as you wanted. There are some problem sets that take advantage of in-"job" multi-processing better than others, just as some problem sets will take of advantage of multiple cores by doing completely different tasks simultaneously. Simple (very) example: copying all of the files between volumes (not a block-for-block clone); if I have two cores, I can can either have a multi-threaded equivalent of "cp" which walks the directory tree of the source and dispatches the create/copy jobs in parallel, each core dropping into the kernel as needed, or I can start a "cpio -o" on one core and pipe it to a "cpio -i" on the other, with a decent block size on the pipe. More cores means more dispatch threads in the first case, and background horsepower handling the low-level disk I/O in the other. In my experience, the "cpio" case works better than the multi-threaded "cp" (due, AFAICT, to the locks on the destination directories).