[Haskell-cafe] RE: Haskell vs. Erlang: The scheduler

Tomasz Zielonka tomasz.zielonka at gmail.com
Tue Jan 3 16:52:20 EST 2006

On Tue, Jan 03, 2006 at 04:36:37PM -0000, Simon Marlow wrote:
> > Is it impractical then to implement this type of app in Haskell?
> > Based on the nature of Haskell scheduling I would be inclined to say
> > yes.
> Absolutely not!
> Apart from the problem you have with a space leak caused by the input
> buffer of the logging thread overflowing, which is easily fixed by using
> a bounded channel, I don't know why you want priorities.  Is there
> something else?
> We could easily add Erlang-style priorities (though without the overhead
> of counting function calls, I'd do it by counting allocations), but I'd
> rather not if we can avoid it.

You could also achieve a similar effect without hacking the RTS, for
example: track the number of elements in a Chan and on writeChan invoke
yield with probability based on the number of elements in Chan - the
more elements the higher the probability. You could experiment with
different probability distributions.

This is assuming that yield will make the thread wait for the next

Best regards

I am searching for programmers who are good at least in
(Haskell || ML) && (math || Linux || FreeBSD)
for work in Warsaw, Poland

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