Re: [Haskell-cafe] Concurrency best practices?

On Sat, Feb 5, 2011 at 8:19 AM, Jesper Louis Andersen wrote:

On Sat, Feb 5, 2011 at 17:13, Andrew Coppin wrote:

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On 05/02/2011 12:56 PM, Jesper Louis Andersen wrote:

Presumably messages added to the channel appear immediately after the transaction commits. The problem is, I think GHC's STM implementation might mean that if two transactions both try to log a message, they both get rolled back...

Yes, this is the performance caveat I was hinting at. When logging becomes heavy and transactions are *not* completing, you will have transaction retries due to the logging. If the transaction completes however, it is not that much of a problem.

I recall reading that clojure has a concept of associative combination. If you can declare that certain operations are associative then the runtime doesn't have to care if they get out of order.