[Haskell-cafe] forkProcess, forkIO, and multithreaded runtime

Donn Cave donn at avvanta.com
Tue Oct 16 22:16:53 CEST 2012

Since we're talking about forkIO here - not forkOS - is it possible
to control the use of OS threads to avoid this problem?  As I
understand it, the problem is with real OS threads.  A program
running entirely in multiple `green' threads will fork to the same
set of threads in the same state, creating no problem with internal

I'm guessing this is why he sees the problem at 9 threads - maybe the
runtime picks up another OS thread at that point.  

Of course one could link the unthreaded RTS, and that will cause
everything, including runtime gc etc., to run in the parent thread,
true?  And there are some runtime options to control number of threads


More information about the Haskell-Cafe mailing list