2010-06-27 10:58:44 +04:00
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name: speculation
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2010-06-27 12:20:12 +04:00
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version: 0.0.2
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2010-06-27 10:58:44 +04:00
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license: BSD3
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license-file: LICENSE
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author: Edward A. Kmett
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maintainer: Edward A. Kmett <ekmett@gmail.com>
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stability: experimental
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2010-06-27 11:44:55 +04:00
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homepage: http://github.com/ekmett/speculation
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2010-06-27 10:58:44 +04:00
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category: Concurrency
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2010-06-27 11:14:35 +04:00
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synopsis: A framework for safe, programmable, speculative parallelism
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2010-06-27 12:20:12 +04:00
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description:
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A framework for safe, programmable, speculative parallelism, loosely based on
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<http://research.microsoft.com/pubs/118795/pldi026-vaswani.pdf>
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.
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@'spec' g f a@ evaluates @f g@ while forcing @a@, if @g == a@ then @f g@ is returned. Otherwise @f a@ is evaluated.
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.
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Furthermore, if the argument has already been evaluated, we avoid sparking the parallel computation at all.
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.
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If a good guess at the value of @a@ is available, this is one way to induce parallelism in an otherwise sequential task.
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.
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However, if the guess isn\'t available more cheaply than the actual answer, then this saves no work and if the guess is
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wrong, you risk evaluating the function twice.
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.
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> spec a f a = a `seq` f a
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.
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The best-case timeline looks like:
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.
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> [---- f g ----]
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> [----- a -----]
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> [-- spec g f a --]
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.
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The worst-case timeline looks like:
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.
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> [---- f g ----]
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> [----- a -----]
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> [---- f a ----]
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> [------- spec g f a -----------]
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.
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Compared to the unspeculated timeline of
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.
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> [---- a -----]
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> [---- f a ----]
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.
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Changes since 0.0.1
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.
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* 'specFoldr1' bug fix
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.
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* Added 'spec'' combinator
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.
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Changes since 0.0.0
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.
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* Added 'WithoutSpeculation' and 'WrappedFoldable'
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2010-06-27 10:58:44 +04:00
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copyright: (c) 2010 Edward A. Kmett
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build-type: Simple
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cabal-version: >=1.2
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tested-with: GHC==6.12.1
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2010-06-27 11:14:35 +04:00
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extra-source-files: README.markdown
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2010-06-27 10:58:44 +04:00
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library
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ghc-options: -Wall
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build-depends:
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base >= 4 && < 6,
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containers >= 0.2.0.1,
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array >= 0.2 && < 0.4,
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parallel >= 2.2 && < 2.3
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exposed-modules:
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Control.Concurrent.Speculation
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