[Haskell-cafe] Re: concurrent haskell: thread priorities

Don Stewart dons at galois.com
Fri Jan 9 14:22:11 EST 2009


marlowsd:
> Neal Alexander wrote:
> >Thomas DuBuisson wrote:
> >>    It seems like we could get some priority based scheduling (and still
> >>    be slackers) if we allow marked green threads to be strictly
> >>    associated with a specific OS thread (forkChildIO?).
> >>
> >>
> >>I think you want the GHC-only GHC.Conc.forkOnIO
> >>
> >GHC.Conc.forkOnIO is helpful but doest work in this case - it doesn't 
> >attach them to the same OS thread.
> 
> But it does attach the thread to a particular "virtual CPU" in the GHC RTS 
> (we call them "capabilities"), with the intention that a virtual CPU 
> corresponds more or less to a real CPU core.

Every time Simon responds on questions of parallelism and the GHC
runtime, I learn something. That indicates to me that we've got a 'bus
error' situation with how to effectively use the smp runtime. 

Simon: time for a multicore FAQ wiki page to gather this knowledge, like
we did for the performance tips? Somewhere to paste these insights?

-- Don


More information about the Haskell-Cafe mailing list