Re: [rules-users] Performance of collect seems to be n-squared

Repeatedly creating this ArrayList is bound to be O(n2). Why do you want the Post facts as a List? There may be better ways for achieving your goal. -W On 13 February 2012 20:49, Shur, Bob <robert.shur(a)hp.com&gt; wrote: > I have a simple class Post { int id; ... }. I insert some number of them > as facts and then call ksession.execute(facts); > > The whole drl file (except for package and import statements) is: > > rule "collect" > when > $a : ArrayList(size > 0) from collect(Post()); > then > System.out.println("Number of posts: " + $a.size()); > System.out.println("DONE"); > end > > The time it takes to run is n-squared in the number of posts. For 4000, > 8000, 16000, 32000, 64000 posts the time is (in 1/10 seconds): > > 4, 14, 56, 220, 852 > > Is this expected? Is there a better way for me to do the collect? > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users