This is the opposite of the point I was trying to make. The coarse-grained parallelism of multi-cores does _not_ map well to the naturally fine-grained parallelism of SIMD (single instruction, multiple data) APL languages. That multi-cores map even less well to serial languages doesn't really help us.
Consider an expression like +/?100$0 on a a dual-core machine. Sure, you could parcel out 50 additions to each core, then add the results but consider how the massive overhead of moving the data and starting up another core would completely swamp the tiny amount of processing required by 50 additions. The advantage of a language like J is in having lightweight code that can be changed easily to (potentially) accomodate multi-cores. In any case, there's no advantage to multi-cores until you are processing quite a lot of data. That's why I use an example of the Netflix problem - which requires looking at relations between a hundred million entries - in the minor example to which I referred. On 12/17/07, Don Guinn <[EMAIL PROTECTED]> wrote: > > To me it seems that APL and J are probably the best languages around to > support multi-core machines as nothing needs to be done to programs > written > in either of these languages to exploit multi-cores. > > On Dec 17, 2007 12:40 PM, Devon McCormick <[EMAIL PROTECTED]> wrote: > > > There has been continued interest on this forum and elsewhere in the APL > > community about taking advantage of the up-and-coming generation of > > multi-core machines. Ideally, this would be transparent to the > programmer > > but this is probably an unrealistic ideal, at least for the near future. > > If > > you take a look at this Slashdot thread - > > http://developers.slashdot.org/article.pl?sid=07/12/17/1635200- you'll > > notice several informed responses focusing on the idea of parallel > > programming as intrinsically different from serial programming. > > > > I've mentioned how I've been able to take advantage of my dual-core > > machine > > for some problems. If anyone else has done this, it might be > instructive > > to > > put up a wiki page or two with some examples of how to do this. A minor > > example is here: > > > > > http://www.jsoftware.com/jwiki/NYCJUG/2007-03-13#head-0c69d286922c2243a3e9c74bb1f06a4d9e88bbfd > > . > > > > -- > > Devon McCormick, CFA > > ^me^ at acm. > > org is my > > preferred e-mail > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- Devon McCormick, CFA ^me^ at acm. org is my preferred e-mail ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
