@hackage pqc0.1

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PQC: QuickCheck in the Age of Concurrency

An SMP parallel QuickCheck driver

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Quick start:

Parallel batch driver for QuickCheck

Run your properties in chunks over multiple cpus.

Building (usual Cabal instructions):

$ runhaskell Setup.lhs configure 
$ runhaskell Setup.lhs build
$ runhaskell Setup.lhs install

Example use in: examples/Example.hs

---

Long story

Do you:

* Have (or want) lots of QuickCheck properties? 
* Run them often (maybe on every darcs commit)? 
* Tired of waiting for the testsuite to finish? 
* Got a multi-core box with cpus sitting idle...? 

Yes? You need Parallel QuickCheck!

PQC provides a single module: Test.QuickCheck.Parallel. This is a QuickCheck driver that runs property lists as jobs in parallel, and will utilise as many cores as you wish, with the SMP parallel GHC 6.6 runtime. It is simple, scalable replacement for Test.QuickCheck.Batch.

An example, on a 4 cpu linux server, running 20 quickcheck properties.

With 1 thread only:
    $ time ./a.out 1
    1: sort1                    : OK, 1000 tests.
    1: sort2                    : OK, 1000 tests.
    1: sort3                    : OK, 1000 tests.
    1: sort4                    : OK, 1000 tests.
    ...
    ./a.out 1 > x  18.94s user 0.01s system 99% cpu 18.963 total

18 seconds, 99% cpu. But I've got another 3 2.80GHz processors sitting
idle! Let's use them, to run the testsuite faster. No recompilation required.

4 OS threads, 4 Haskell threads:
    $ time ./a.out 4 +RTS -N4 > /dev/null
    ./a.out 4 +RTS -N4 > /dev/null  20.65s user 0.22s system 283% cpu 7.349 total

283% cpu, not bad. We're getting close to being limited by the
length of the longest running test.

Or on a dual core macbook, thanks to Spencer Janssen for macbook data and testing:

1 thread:
    ./Example 1 
    17.256s

2 thread:
    ./Example 2 +RTS -N2 
    10.402s

Get it!

Homepage: http://www.cse.unsw.edu.au/~dons/pqc.html
Haddocks: http://www.cse.unsw.edu.au/~dons/pqc/
Example : http://www.cse.unsw.edu.au/~dons/code/pqc/examples/Example.hs

darcs get http://www.cse.unsw.edu.au/~dons/code/pqc