https://github.com/winterland1989/unboxed-ref

Fast unboxed references for ST and IO monad
https://github.com/winterland1989/unboxed-ref

Last synced: 9 days ago
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Fast unboxed references for ST and IO monad

• Host: GitHub
• URL: https://github.com/winterland1989/unboxed-ref
• Owner: winterland1989
• License: bsd-3-clause
• Created: 2017-05-08T11:00:59.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2017-07-17T09:33:54.000Z (over 7 years ago)
• Last Synced: 2024-09-17T10:08:08.198Z (about 2 months ago)
• Language: Haskell
• Homepage:
• Size: 10.7 KB
• Stars: 16
• Watchers: 5
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: ChangeLog.md
  • License: LICENSE

Awesome Lists containing this project

README

        
unboxed-ref

===========

[![Hackage](https://img.shields.io/hackage/v/unboxed-ref.svg?style=flat)](http://hackage.haskell.org/package/unboxed-ref)

[![Test Status](https://img.shields.io/travis/winterland1989/unboxed-ref.svg)](https://travis-ci.org/winterland1989/unboxed-ref)

This package provide fast unboxed references for `ST` and `IO` monad and atomic operations for `IORefU Int` type. Unboxed reference is implemented using single cell `MutableByteArray s` to eliminate indirection overhead which `MutVar# s a` carry, on the otherhand unboxed reference only support limited type(instances of `Prim` class).

A simple diagram could show the difference between `IORef Int` with `IORefU Int`:

```

data Foo = Foo {-# UNPACK #-} (IORef Int)

        +-----------+    +-------------+    +---------+

        | Foo |  *  +--->+ MutVar# | * +--->+ I# | i# |

        +-----------+    +-------------+    +---------+

data Bar = Bar {-# UNPACK #-} (IORefU Int)

        +-----------+    +------------------------+

        | Bar |  *  +--->+ MutableByteArray# | i# |

        +-----------+    +------------------------+

```

Benchmark

---------

Modified from [this benchmark](https://marcotmarcot.wordpress.com/2010/03/13/performance-of-ioref/).

```bash

$ cd bench && cabal build

$ time ./dist/build/bench-ref/bench-ref

143

./dist/build/bench-ref/bench-ref  19.76s user 0.02s system 99% cpu 19.785 total

------------------------------------------------------------

$ time ./dist/build/bench-unboxed-ref/bench-unboxed-ref

143

./dist/build/bench-unboxed-ref/bench-unboxed-ref  16.66s user 0.02s system 99% cpu 16.694 total

------------------------------------------------------------

$ ./dist/build/bench-unboxed-ref-atomic/bench-unboxed-ref-atomic

50500000

------------------------------------------------------------

$ ./dist/build/bench-ref-atomic/bench-ref-atomic

3597361

```