On Tue, Sep 28, 2010 at 11:38 AM, Romain Demeyer
wrote:
> Does it means that the value is computed by the "caller", based on the
> thunk, and not by the worker itself?
It is computed by the one who needs the value. Your worker doesn't.
Note that the value is computed on 'print', which is *after*
Thanks for your help. It's more clear now.
> The value is not being evaluated by STM at all, as your STM functions
> don't need the value. In your program is evaluating when you print
> the answer in the main thread, as printing requires the value of the
> computation. If you didn't print, nothi
On Tue, Sep 28, 2010 at 10:06 AM, Romain Demeyer
wrote:
> Let's a function "do_job", the function to execute by the threads (the
> workers) :
> do_job :: (b -> a) -> b -> Inbox a -> IO ()
> do_job f input inbox = do { value <- return (f input)
> ; atomically ( writeMsg in
Excerpts from Romain Demeyer's message of Tue Sep 28 09:06:53 -0400 2010:
> That's what we want, but what is the explanation of this behavior? STM is
> designed to be optimistic, not blocking. So, does it means that the "value"
> is evaluated at "commit-time"?
> Do you know some problems that are r
Hi,
I'm working on Concurrent Haskell, especially with the monad STM. I don't
fully understand the way my program is executed. I think the lazy evaluation
leads to a loss of performance, if we don't pay attention to this problem. A
short example will be more explicit :
Imagine this scenario : we
