rparallel : Racket in parallel🔗ℹ

License: LGPL-3.0-or-later

1 Introduction🔗ℹ

This package provides high-level parallel forms.

The implementation relies on Racket futures. Due to coordination overhead the library is only useful to parallelize computationally instensive code. For instance, consider the following:

(parallel-map sqrt (range 1000000))

Here the parallel form creates several futures whose overhead vastly prevails over the relatively cheap sqrt operation. This leads to a much slower computation than the respective serial map call. To take advantage from multiple processor, larger chunks of computation needs to be distributed over fewer futures, for instance:

(parallel-let ((x (map sqrt (range 1000)))

(y (map sqrt (range 1000) (range 1000000))))

(append x y))

See Parallelism with Futures for further subtleties related to the use of futures.

2 Interface🔗ℹ

See pmap : Parallel map for alternative parallel map procedures that leverage both Racket futures and places forms of parallelism.