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Efficient, general purpose pseudo-random number generation

This package provides the System.Random.MWC module, a Haskell library for generating high-quality pseudo-random numbers in a space- and time-efficient way.

Performance

This library has been carefully optimised for high performance. To obtain the best runtime efficiency, it is imperative to compile libraries and applications that use this library using a high level of optimisation.

Suggested GHC options:

-O -fvia-C -funbox-strict-fields

To illustrate, here are the times (in seconds) to generate and sum 250 million random Word32 values, on a laptop with a 2.4GHz Core2 Duo P8600 processor, running Fedora 11 and GHC 6.10.3:

no flags   200+
-O           1.249
-O -fvia-C   0.991

As the numbers above suggest, compiling without optimisation will yield unacceptable performance.

Get involved!

Please report bugs via the bitbucket issue tracker.

Master Mercurial repository:

  • hg clone http://bitbucket.org/bos/mwc-random

There's also a git mirror:

  • git clone git://github.com/bos/mwc-random.git

(You can create and contribute changes using either Mercurial or git.)

Authors

This library is written and maintained by Bryan O'Sullivan, bos@serpentine.com.