Craig Henderson wrote:
I am very interested to hear any comment on design, code, performance or any other area.
Some comments: * Why do your function object expose a static method instead of being real functor or polymorphic function object. What's the rationale being this choice ? * Why are timing stats embedded into the library ? I may want to not time thing and don't want to suffer from w/e memory footprint of those additional member. * The interface is, on the user side, extremely verbose. I think some functions could extract more information from their input type to lessen the amount of type definition the user has to write. Using the result_of protocol here and there could also prevent people to have to memorize various unrelated name for inner types. * Giving performances figures is OK. Comparing them to sensible existing solution is better. How fast are you with respect to a similar, hand coded application using Boost.thread or even openMP. Instead of giving absolute time,a better metric could be using cycles per processed elements as it gives an architecture independent measure of performances. * On the same topic, why not providing an openMP version on compiler that can support it ? * Give examples of other types of application that can benefit or can't benefit from MapReduce. Can I wrote Image processing with it? HPC ? Which caracteristics should my original application have to benefit from MR ? Counting and sorting words is ok for a tutorial but it doesn't give en incentive on how/why to use this library. Now, it's time for my Google Syndrom rant. For intellectual honesty, it could be nice if people could stop delivering the false sense that everything is invented by Google Lab. MapReduce is only the latest incarnation of a 20+ years research effort on pattern for high-level parallelism (being skeleton, Parallel Design pattern or Bilks ynchronosu parallelism). As it seems Google researcher can't bother doing their homework and provide a proper bibliography, it could be nice if someone actually do it. -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35