Raul Miller-4 wrote: > > On Mon, Apr 27, 2009 at 6:52 PM, Viktor Cerovski > <viktor.cerov...@gmail.com> wrote: >> Raul Miller-4 wrote: >>> I believe, in the context of J, the word "Actor" should be taken to mean >>> "Program". >> >> Raul, I disagree, because Actors are about writing explicitly parallel >> programs, while J programs are at best and currently in principle, >> only implicitly parallel. > > Could you state this distinction using concrete examples? > > To illustrate my confusion: I can run several J programs simultaneously > and > they can all be writing to the file system and reading from the file > system > and their changes will be happening in parallel. Are you saying that > because > I do not have a keyword in J that says "PARALLEL", I am using "implicit > parallelism" rather than "explicit parallelism"? If this is the > distinction, > can you tell me what advantages "explicit parallelism" would have? > Basically, we can't just have programs writing things into files without some kind of explicit mutex mechanism, and, in more complicated parallel programs, taking care of possible deadlocks, etc.
Or, say we want to fork two queries that cannot be easily fine-grain parallelized into two threads and continue with something else while waiting for results. > I say only because just as it is clear that auto-vectorization inherent > in J is finely adopted to the multi-core processors, it is also clear that > auto-vectorization is not going to solve all the problems of parallel > programming. Or perhaps you are thinking of a system which only has one program (one "actor", from my point of view) as opposed to a system which has multiple programs? Yes, exactly. Now then the whole issue is when you run several programs, what facilities given language provides for creating, exchanging data, etc between these running programs. The parallel programming question is sort of the opposite one: what facilities given language provides to solve a problem using several (A)c(t)or(e)s at once, i.e concurrently. -- View this message in context: http://www.nabble.com/concurrency-via-the-Actor-model-tp23249986s24193p23268278.html Sent from the J Programming mailing list archive at Nabble.com. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
