Man, this is exactly how I feel after all this tinkering! It was great for learning Clojure a bit more in depth, but in the end I am going to stick with the Java solution. Especially since it's so easy to mix Java and Clojure in the same project! I just specify :java-source-paths ["src/java"] in my project.clj and I just call that one method when I need it and the rest of the project is in Clojure. I think when performance if critical idiomatic Clojure is to just drop down to Java :)
Christophe's second function actually achieves Java speed or very close (within 5-10%), but it's ugly and there's a bit more to my algorithm which would make it even uglier if I were to go that route. On Thursday, February 21, 2013 4:55:13 AM UTC-5, Marko Topolnik wrote: > > Whatever the final performance achieved, the fact remains that the > original Java code was much cleaner, simpler, and more comprehensible than > the big ball of mud the performant Clojure version is turning into. > > I have my own piece of performance-critical code that I used to maintain > and improve over a timespan of many months. I finally gave in and recoded > the thing in Java. It took only a couple of hours and the result was nice, > clean, idiomatic Java code, with completely predictable performance > characteristics, as opposed to the Clojure version where it took many hours > of staring at ridiculuously counterintuitive stacktraces in VisualVM to > find what to optimize and how. The amount of code is about the same at > either end. > > > On Thursday, February 21, 2013 10:41:55 AM UTC+1, Christophe Grand wrote: >> >> I updated my answer on SO, with a deftype-based one that gives me an >> additional 30% boost. >> >> >> On Tue, Feb 19, 2013 at 6:38 PM, Geo <ggrig...@gmail.com> wrote: >> >>> What about the call to .equals? >>> >>> >>> On Tuesday, February 19, 2013 12:20:28 PM UTC-5, Marko Topolnik wrote: >>>> >>>> The difference between String[] and Object[] is that a member of the >>>> former doesn't need a checked cast to String, but the latter does need >>>> one. >>>> In the code under consideration, however, nothing specific to String is >>>> used, so even in the Java code you can freely replace String[] with >>>> Object[] and everything still works. >>>> >>>> If, on the other hand, you needed to invoke say *substring*, you'd see >>>> a small penalty due to the checked cast operation. >>>> >>>> On Tuesday, February 19, 2013 5:52:31 PM UTC+1, Andy Fingerhut wrote: >>>>> >>>>> ^objects is a Clojure synonym for ^"[Ljava.lang.Object;". Note that >>>>> there are such synonyms for only a few Java types, not everything, e.g. >>>>> there is no ^strings. >>>>> >>>>> What you are hinting is that a1 and a2 are Java arrays of objects. I >>>>> think this might speed up (aget a1 i) expressions, since it is known that >>>>> a1 is an array of objects, but I'm not sure about that. I believe "under >>>>> the hood" in the JVM all arrays of Objects are treated the same, >>>>> regardless >>>>> of whether those Objects are String, Integer, java.awt.Color, etc. >>>>> >>>>> Andy >>>>> >>>>> On Feb 19, 2013, at 8:46 AM, Geo wrote: >>>>> >>>>> One thing I don't get is that switching the type hints from >>>>> >>>>> [#^"[Ljava.lang.String;" a1 #^"[Ljava.lang.String;" a2] >>>>> >>>>> to [^objects a1 ^objects a2] didn't seem to have any negative impact >>>>> on performance. Can anyone explain why hinting ^objects is just as good >>>>> as >>>>> specifying that it's an array of Strings? What are you hinting with >>>>> ^objects that Clojure doesn't already know? >>>>> >>>>> -- >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Clojure" group. >>> To post to this group, send email to clo...@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+u...@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+u...@googlegroups.com. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >>> >>> >> >> >> >> -- >> On Clojure http://clj-me.cgrand.net/ >> Clojure Programming http://clojurebook.com >> Training, Consulting & Contracting http://lambdanext.eu/ >> > -- -- 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/groups/opt_out.
