Gah. Meant in project.clj: :jvm-opts ^:replace ["-server"] ;; maybe also set max heap with "-Xmx1g" in there
On Thursday, May 14, 2015 at 2:46:59 PM UTC-5, Alex Miller wrote: > > Oh also, the default Leiningen settings are optimized for reducing > startup, not for speed. Use: > > ^:jvm-opts ^:replace ["-server"] ;; maybe also set max heap > with "-Xmx1g" in there > > Or just don't use lein when perf testing. > > On Thursday, May 14, 2015 at 2:44:38 PM UTC-5, Alex Miller wrote: >> >> The major problem here is that you are using boxed math for everything >> instead of primitives. >> >> 0) Switch to Clojure 1.7.0-beta3 - it's faster and some things below are >> dependent on it for best performance. And use Java 1.8. >> 1) Parse the lines you're reading directly into longs (Clojure focuses on >> 64-bit primitives - longs and doubles) >> 2) Put the longs first into a data structure that preserves the primitive >> type. The two best options for that here are records (which can have >> primitive fields) and arrays. I would create a Canvas defrecord with ^long >> width and height and a Paper defrecord with all ^long fields for example. >> 3) Store the papers in a vector (using transient to create it) >> 4) I suspect visible-color and covered? could probably be tightened up >> into a reduce over papers or a single loop-recur over papers - can't say I >> totally get what's happening there. >> 5) In visible-color-frequencies, you could use "update" instead of get + >> transient assoc! on the acc map, but this is never going to be terribly >> fast. Another option here would be to create an array with the max color >> (you could track that while reading if it's not a well-known answer) and >> bash the array. That can retain int or long counters and will be *way* >> faster. >> 6) You can use (set! *unchecked-math* :warn-on-boxed) to get faster math >> (no overflow checks) and also issue warnings (added in 1.7) if you happened >> to use boxed math by accident. >> >> >> >> On Thursday, May 14, 2015 at 3:02:42 AM UTC-5, Amith George wrote: >>> >>> I wrote the following code to solve this challenge - >>> https://www.reddit.com/r/dailyprogrammer/comments/35s2ds/20150513_challenge_214_intermediate_pile_of_paper/ >>> . >>> >>> Code - >>> https://github.com/amithgeorge/reddit-dailyprogrammer-clojure/blob/56ce1dbb6a08e96150dc85934caecfeb68108a53/src/rdp/214_intermediate.clj >>> >>> I executed the -main function using `lein run 1`. >>> >>> Output >>> >>> ;; lein run 1 >>> >>> 0 12605919 >>> 1 3578145 >>> 2 15356894 >>> 3 19134293 >>> 4 2394558 >>> 5 15030409 >>> 6 6424953 >>> 7 14893444 >>> 8 1592254 >>> 9 1914025 >>> 10 7075106 >>> "Elapsed time: 501168.972435 msecs" >>> >>> The code originally used an immutable hashmap, but I lost patience >>> waiting for the computation to end. With mutable hashmap, it still takes >>> around 8 mins. >>> >>> I wrote a C# version of the above code - >>> https://gist.github.com/amithgeorge/766b8220f39d48221e58. It finishes >>> under 40secs. The C# exe was built under Release mode and executed directly >>> from the commandline. I expected the Clojure version to perform similarly. >>> >>> Any tips on what I am doing wrong? >>> >>> ----- >>> Explanation of the code - Create a vector of all paper sheets, such that >>> the sheet placed last is the first element of the vector and the last >>> element is the canvas. To compute the frequency of each visible color - for >>> each point in the canvas find the first sheet in the vector that covers the >>> point. Store/increment its count in the hashmap. I understand there might >>> be better more efficient ways to solve this, but currently I am interested >>> in why the Clojure versions is so slow vis-a-vis the C# version. >>> >>> -- 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.
