It appears to be a difficult/interesting logistics/otpimisation problem, to split a calculation into chunks for multiple processors. One advantage of not doing it is that you can run a program for ages and still have a responsive computer for other stuff running on the other core.
On 12 February 2010 16:52, Don Guinn <[email protected]> wrote: > Array languages are easier to spread over multiple processors. And J > applications would probably extend to multiple processors with no or very > little work. But each core is a scalar processor. The J engine would have > to > divide the vector and operations that can be parallelized into scalar tasks > for each core. Not an easy task, as can be seen by all the complexities > required to support multiple cores for scalar languages like C. > > On Fri, Feb 12, 2010 at 9:41 AM, Matthew Brand <[email protected] > >wrote: > > > It only appears to use one core at a time so on dual core, CPU usage > > reaches > > 50%. > > > > Would calculations take half as long if it used both? I suppose it > depends > > on what the calculation is. But isn't one of the touted benefits of array > > based languages meant to be ease of parrallisation (now I know I must > have > > spelt that incorrectly!). > > > > On 12 February 2010 16:28, Devon McCormick <[email protected]> wrote: > > > > > Based on my experience with two cores, the OS seems smart enough to use > > the > > > other core for a separate J process if one core is busy. > > > > > > On Fri, Feb 12, 2010 at 11:19 AM, Raul Miller <[email protected]> > > > wrote: > > > > > > > On Fri, Feb 12, 2010 at 11:09 AM, Jan Jacobs < > [email protected] > > > > >wrote: > > > > > > > > > ls, > > > > > I want to upgrade my PC from single core to a quad core version, > with > > > 4GB > > > > > RAM. How does J scale with number of processors? Has J ways of > > > > configuring > > > > > a > > > > > quad core system to support this? When it doesn't, is it worthwhile > > to > > > > port > > > > > the application to 4 separate communicating J sessions or are there > > > other > > > > > solutions? Currently I use J504 and J64 Windows XP 64. > > > > > Thanks in advance for your help. > > > > > > > > > > > > > Current versions of J use only one core per J process. > > > > > > > > FYI, > > > > > > > > -- > > > > Raul > > > > > ---------------------------------------------------------------------- > > > > 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 > > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
