Re: [Haskell-cafe] why PArr slower than list ?

Albert Lee:

I read the GHC/Data Parallel Haskell/GHC.PArr page http://haskell.org/haskellwiki/Data_Parallel_Haskell/GHC.PArr

and make a simple test to compare the speed of PArr against List:

On the wiki page GHC.PArr is described under the heading "Convenience without the speed". You'd usually still expect it not to be slower than lists. However, lists are optimised by GHC (buildr/fold fusion), where the implementation of GHC.PArr at this point is complete naive. Manuel