Thank you very much. I'm using the Colt random number generator directly. I've managed to reduce computing time by orders of magnitude using type hints and java arrays in some critical parts. I haven't had the time to write a report on this for the list, since have been busy with other projects, but this will come as well as the release of the source code.
Thanks again, Jose. On Tuesday, June 3, 2014 1:46:55 PM UTC-4, Mars0i wrote: > > Jose, > > This is an old thread, and whatever problems you might be dealing with > now, they're probably not the same ones as when the thread was active. > However, I think that if parallel code uses the built-in Clojure random > number functions, there is probably a bottleneck in access to the RNG. > With Criterium's bench function on an 8-core machine: > > (def ones (doall (repeat 1000 1))) > (bench (def _ (doall (map rand ones)))) ; 189 microseconds average time > (bench (def _ (doall (pmap rand ones)))) ; 948 microseconds average time > > One solution that doesn't involve generating the numbers in advance is to > create separate RNGs, as discussed in this thread > <https://groups.google.com/forum/#!searchin/clojure/random/clojure/cRVS19PB06E/8FsmtsYx6SkJ>. > > This is a strategy that I am starting to explore. > > Related notes for anyone interested: > > As of Incanter 1.5.5 at least some functions such as sample are based on > Clojure's bult-in rand, so they would have this problem as well. > > clojure.data.generators allows rebinding the RNG, and provides > reservoir-sample and a replacement for the default rand-nth. > > The bigml/sampling > <https://github.com/bigmlcom/sampling/tree/master/src/bigml/sampling> > library provides sampling and random number functions with optional > generation of a new RNG. > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
