Showing posts with label futures. Show all posts
Showing posts with label futures. Show all posts

2009-12-07

Futures: Fine Grained Parallelism in PLT

We're pleased to announce the initial release of parallel futures, a construct for fine-grained parallelism in PLT. Roughly speaking, a programmer passes a thunk to 'future' and it gets run in parallel. That "roughly" holds a few gotchas, partly because we're just getting started and partly due to the technique we're using. See the documentation for more details:

http://pre.plt-scheme.org/docs/html/futures/

If you've got a multicore machine where you can't keep the cores busy or your office/machine room is a bit cold, try this program:

#lang scheme
(require scheme/future)
(define (loop) (loop))
(for-each
 touch
 (for/list ([i (in-range 0 (processor-count))])
  (future loop)))
Note that you have to build mzscheme with futures; it isn't enabled by default, but see the docs above for how to do that. Beyond the above, we've also gotten a few parallel kernels going and are seeing good scalability up to 8 cores (the biggest machine we have around for the time being).