runhaskell a parallel program

Bulat Ziganshin bulat.ziganshin at
Thu May 7 09:45:29 EDT 2009

Hello Simon,

Thursday, May 7, 2009, 5:24:54 PM, you wrote:

>> A related question I wanted to ask. Is there any way to have my
>> Haskell program support -j3, which is equivalent to +RTS -N3 -RTS. At
>> the moment I've set this up with a shell script to translate the -j3,
>> but a nicer method would be preferable. Even something as sledgehammer
>> like as restartWithNProcessors :: Int ->  IO (), which aborted the
>> program entirely and restarted main with a completely fresh heap but a
>> given number of processors.

Neil, you can implement it by yourself - convert -j3 in cmdline to
+RTS -N3 -RTS and run program itself. alternatively, you can use
defaultsHook() although i'm not sure that it can change number of

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at

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