[Haskell-cafe] Re: Hugsvs GHC (again)was: Re: Somerandomnewbiequestions

[Simon Marlow]

On 19 January 2005 16:49, Keean Schupke wrote:

> But what about the continuing computation... we do not want
> the fastest IO system, but we want the program to comlete the
> fastest... So ideally we want 2 threads!
> 
> One runs the Haskell code that is not waiting for IO. (IE other
> Haskell threads)... The other runs a select loop as you suggest!
> 
> This way the number of threads is fixed (2) and execution never
> 'blocks' for IO. (Simon, what about this scheme?)

This is what GHC does, if I understand you correctly.  The thread
running select() does so in its own OS thread, while another OS thread
runs the Haskell code.  As long as you use -threaded, that is.  Oh, and
before GHC 6.4 it was done a different way - the scheduler used to do
the select() between running Haskell threads.

Cheers,
	Simon