speculation: A framework for safe, programmable, speculative parallelism
A framework for safe, programmable, speculative parallelism, loosely based on http://research.microsoft.com/pubs/118795/pldi026-vaswani.pdf
evaluates spec
g f af g
while forcing a
, if g == a
then f g
is returned. Otherwise f a
is evaluated.
Furthermore, if the argument has already been evaluated, we avoid sparking the parallel computation at all.
If a good guess at the value of a
is available, this is one way to induce parallelism in an otherwise sequential task.
However, if the guess isn't available more cheaply than the actual answer, then this saves no work and if the guess is wrong, you risk evaluating the function twice.
spec a f a = a `seq` f a
The best-case timeline looks like:
[---- f g ----] [----- a -----] [-- spec g f a --]
The worst-case timeline looks like:
[---- f g ----] [----- a -----] [---- f a ----] [------- spec g f a -----------]
Compared to the unspeculated timeline of
[---- a -----] [---- f a ----]
Changes since 0.0.1
specFoldr1
bug fixAdded
spec'
combinator
Changes since 0.0.0
Added
WithoutSpeculation
andWrappedFoldable
[Skip to Readme]
Versions [faq] | 0.0.0, 0.0.1, 0.0.2, 0.1.0, 0.2.0, 0.3.0, 0.4.0, 0.5.0, 0.5.1, 0.6.0, 0.7.0, 0.8.0, 0.8.0.1, 0.8.0.2, 0.8.1.0, 0.8.2.0, 0.9.0.0, 1.0.0.0, 1.1.0.0, 1.2.0.0, 1.2.0.1, 1.2.0.2, 1.3, 1.4, 1.4.1, 1.4.1.1, 1.4.1.2, 1.5, 1.5.0.1, 1.5.0.2, 1.5.0.3 |
---|---|
Dependencies | array (>=0.2 && <0.4), base (>=4 && <6), containers (>=0.2.0.1), parallel (==2.2.*) [details] |
License | BSD-3-Clause |
Copyright | (c) 2010 Edward A. Kmett |
Author | Edward A. Kmett |
Maintainer | Edward A. Kmett <ekmett@gmail.com> |
Category | Concurrency |
Home page | http://github.com/ekmett/speculation |
Uploaded | by EdwardKmett at Sun Jun 27 08:20:09 UTC 2010 |
Distributions | NixOS:1.5.0.3 |
Downloads | 12138 total (326 in the last 30 days) |
Rating | 2.0 (votes: 1) [estimated by rule of succession] |
Your Rating | |
Status | Docs uploaded by user Build status unknown [no reports yet] |
Downloads
- speculation-0.0.2.tar.gz [browse] (Cabal source package)
- Package description (as included in the package)