[Haskell-cafe] forkIO on GHCI does not seem to spawn the thread in the background on some OSs

David Leimbach leimy2k at gmail.com
Wed Feb 9 18:21:49 CET 2011

> > It is  not always a thread.  ForkIO creates a spark and then the
> > scheduler  decides when sparks should be scheduled to threads.  Thus
> > you get a  guarantee of concurrent but not parallel execution.
> That is not correct - it is "par" that creates sparks may be discarded.

I guess I should have been clearer.  A forkIO thread is not an OS thread
necessarily.  Sparks may become threads or be discarded in the par sense.

> forkIO always creates new threads, though it is of course up to the
> scheduler
> when the threads are executed, and how many cores are used.

Yes, this is my understanding as well.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20110209/ebdf0209/attachment.htm>

More information about the Haskell-Cafe mailing list