Issue #5337 has been reported by Masaki Matsushita. ---------------------------------------- Feature #5337: Use outbufs in FileUtils.compare_stream http://redmine.ruby-lang.org/issues/5337 Author: Masaki Matsushita Status: Open Priority: Normal Assignee: Category: lib Target version: 1.9.x =begin I propose using outbufs in FileUtils.compare_stream. It will increase performance. I executed the following code to performance test. require 'fileutils' require "stringio" str = "hoge" * 100000000 a = StringIO.new(str) b = StringIO.new(str) FileUtils.compare_stream(a, b) The following are results of time command. present compare_stream: 1.27s user 0.69s system 96% cpu 2.036 total 1.38s user 0.69s system 96% cpu 2.152 total 1.12s user 0.24s system 98% cpu 1.379 total patched compare_stream: 0.70s user 0.43s system 97% cpu 1.158 total 0.72s user 0.27s system 98% cpu 1.010 total 0.62s user 0.28s system 98% cpu 0.915 total Patched ruby passes tests in test/fileutils. =end -- http://redmine.ruby-lang.org