forkOS should work as well, assuming you have OS threads, like in linux 2.6. You should probably be using the -smp compiler flag and not the -threaded compiler flag, I'm guessing, and make sure that your +RTS arguments indicate that you want to use X total concurrent threads...
-- Jeff On Tuesday 13 March 2007 13:10, Dusan Kolar wrote: > Yes, it works for operator /par/. That's what I've reported. But should > it work for forkIO and forkOS? Could anybody give more detailed answer > than yes, no? :-) (Link to the Web is OK.) > > BTW, thanks for the link to the paper (moreover, I can see, that > googling over haskell.org is not sufficient ;-) ). > > Regards, > > Dusan > > Pepe Iborra wrote: > > On 13/03/2007, at 17:46, Jefferson Heard wrote: > >> Simon will probably chime in on it as well, but his paper on the > >> subject is > >> the best there is: > >> > >> http://research.microsoft.com/~simonpj/Papers/strategies.ps.gz > > > > It does work in GHC 6.6 very nicely. > > You can try it with the following naive fib function, extracted from > > the paper mentioned above: > > > > \begin{code} > > import Control.Parallel > > import System.Environment > > import Fib > > > > main = do > > (x:_) <- getArgs > > print$ pfib (read x) > > > > pfib 0 = 1 > > pfib 1 = 1 > > pfib n = n1 `par` n2 `seq` n1+n2+1 > > where (n1,n2) = (pfib(n-1), pfib(n-2)) > > \end{code} > > > > pep:~/code/snippets/Parallelism$ ghc --make -O Main -threaded > > > > pep:~/code/snippets/Parallelism$ time src/Main 33 > > 11405773 > > > > real 0m1.444s > > user 0m1.343s > > sys 0m0.020s > > > > pep:~/code/snippets/Parallelism$ time src/Main 33 +RTS -N2 > > 11405773 > > > > real 0m0.764s > > user 0m1.367s > > sys 0m0.030s > > > > > > > > Got a speedup of 100%, and didn't use threads at all. Yay! > > > > pepe > > > > _______________________________________________ > > Haskell-Cafe mailing list > > Haskell-Cafe@haskell.org > > http://www.haskell.org/mailman/listinfo/haskell-cafe _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
