runhaskell a parallel program

Bulat Ziganshin bulat.ziganshin at
Thu May 7 06:37:53 EDT 2009

Hello Neil,

Thursday, May 7, 2009, 2:27:34 PM, you wrote:

> This is a test framework that spawns system commands. My guess is the
> Haskell accounts for a few milliseconds of execution per hour. Running
> two system commands in parallel gives a massive boost.

> 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

my own program creates a lot of parallel threads without using -N

the secret is using of forkOS plus C code in threads. since you
spend time in system calls this should also work for you

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at

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