From: "matz (Yukihiro Matsumoto)" Date: 2012-04-03T17:47:28+09:00 Subject: [ruby-core:44102] [ruby-trunk - Bug #6183][Assigned] Enumerator::Lazy performance issue Issue #6183 has been updated by matz (Yukihiro Matsumoto). Status changed from Rejected to Assigned Assignee set to nobu (Nobuyoshi Nakada) Priority changed from Normal to Low Nobu, could you review the patch? And if you don't see any problem, check it in? Matz. ---------------------------------------- Bug #6183: Enumerator::Lazy performance issue https://bugs.ruby-lang.org/issues/6183#change-25631 Author: gregolsen (Innokenty Mikhailov) Status: Assigned Priority: Low Assignee: nobu (Nobuyoshi Nakada) Category: Target version: ruby -v: ruby 2.0.0dev (2012-03-17 trunk 35075) [x86_64-linux] I benchmarked Enumerator::Lazy and that's what I got: user system total real Lazy: 0.690000 0.010000 0.700000 ( 0.733160) Normal: 0.160000 0.010000 0.170000 ( 0.186695) It seems like even with 4 chain links and 3000 elements in initial array, Lazy enumerator is almost 4(!) times slower than the normal case. Instead of performance benefit we've got 4 times performance drawback. See test file attached. -- http://bugs.ruby-lang.org/