On Wed, Apr 9, 2008 at 10:22 PM, Justin Bailey wrote:

...

main = print $ parMap rnf fib $ take 80 $ randomRs (30,35) (mkStdGen

2008/4/9 Sebastian Sylvan : 123)

Does the strategy "rwhnf" do it for you?

Justin

Nope! This is GHC 6.8.2 btw, downloaded the binary from the web site, so it's nothing strange. -- Sebastian Sylvan +44(0)7857-300802 UIN: 44640862

On Wed, Apr 9, 2008 at 10:58 PM, Justin Bailey wrote:

On Wed, Apr 9, 2008 at 2:25 PM, Sebastian Sylvan wrote:

...

Nope!

This is GHC 6.8.2 btw, downloaded the binary from the web site, so it's nothing strange.

On my hyper-threaded CPU, your original code works fine. With -N2, I see 100% CPU. With N1, only 50%. I am also using GHC 6.8.2.

Justin

Hmm, that's curious. I compile with "ghc --make -threaded partest.hs -o par.exe", and then run it with "par.exe +RTS -N2 -RTS". Am I making some silly configuration error? Are you running this on windows? -- Sebastian Sylvan +44(0)7857-300802 UIN: 44640862

On Wed, Apr 9, 2008 at 11:10 PM, Justin Bailey wrote:

On Wed, Apr 9, 2008 at 3:03 PM, Sebastian Sylvan wrote:

...

Hmm, that's curious. I compile with "ghc --make -threaded partest.hs -o par.exe", and then run it with "par.exe +RTS -N2 -RTS". Am I making some silly configuration error? Are you running this on windows?

Yep, that's the command line I used and I am running XP.

Justin

That is indeed weird. The only difference seems to be that you have hyperthreading, whereas I have dual cores. But as I mentioned, manual parallelism works (using forkIO)... -- Sebastian Sylvan +44(0)7857-300802 UIN: 44640862

On Fri, Apr 11, 2008 at 10:43 AM, Don Stewart wrote:

sebastian.sylvan:

...

On Wed, Apr 9, 2008 at 10:58 PM, Justin Bailey <[1]jgbailey@gmail.com

wrote:

On Wed, Apr 9, 2008 at 2:25 PM, Sebastian Sylvan <[2]sebastian.sylvan@gmail.com> wrote: > Nope! > > This is GHC 6.8.2 btw, downloaded the binary from the web site, so it's > nothing strange.

On my hyper-threaded CPU, your original code works fine. With -N2, I see 100% CPU. With N1, only 50%. I am also using GHC [3]6.8.2. Justin

Hmm, that's curious. I compile with "ghc --make -threaded partest.hs -o par.exe", and then run it with "par.exe +RTS -N2 -RTS". Am I making some silly configuration error? Are you running this on windows?

I think its always worth using -O or -O2 too, for what its worth.

Yes I've tried both, neither helped. -- Sebastian Sylvan +44(0)7857-300802 UIN: 44640862