Comentários sobre: Playing with criterion http://marcotmarcot.wordpress.com/2010/05/23/playing-with-criterion/ Thu, 27 Oct 2011 14:34:27 +0000 hourly 1 http://wordpress.com/ Por: Twan van Laarhoven http://marcotmarcot.wordpress.com/2010/05/23/playing-with-criterion/#comment-54 Sun, 23 May 2010 19:25:48 +0000 http://marcotmarcot.wordpress.com/?p=94#comment-54 You are missing a “-O2″ in your invocation of Ghc, so these tests are run without optimizations.

The reason why more than 2 threads could be helpful is because the workloads are not balanced. With two threads, one does 1.618 times as much work as the others, since one is calculating “fib 30″ and the other “fib 31″. With 4 threads one core will do only 1.118 times as much work as the other, it does “fib 28″ and “fib 30″, while the other does “fib 29″ twice.

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