Bug #8129

Updated by nobu (Nobuyoshi Nakada) about 7 years ago

 I created a simple ruby script: 


 #! /usr/bin/env ruby 

 raise "need a file name" unless ARGV[0] 
 contents =[0]) 

 326_000.times do |i| 
   contents[(i + 23) % contents.size] 

 And I uploaded two files below. One is all ASCII characters and the other has a single Unicode character in the first line (an "em dash"). 

 String#index has dramatically different performance for the two strings. Locally, I'm seeing ~1.5 seconds with all_ascii.css and ~30 seconds with one_unicode.css on 1.9.3-p385. It gets worse with ruby 2.0, all_ascii.css still takes ~1 sec, but one_unicode.css takes ~2.5 minutes! 

 Any idea why the performance is so dramatically different between the two?