Explorations of Ruby 1.9.3, CastOff, and JRuby performance on fib and tarai

gistfile1.txt

# Real fixnums obviously helps a lot in 1.9.3 and CastOff.

ruby-1.9.3-p0 ~/projects/jruby $ ruby -v bench/bench_fib_float_recursive.rb 5 30ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin10.8.0]
832040.0
  0.330000   0.000000   0.330000 (  0.336662)
832040.0
  0.330000   0.000000   0.330000 (  0.330731)
832040.0
  0.340000   0.000000   0.340000 (  0.331758)
832040.0
  0.330000   0.000000   0.330000 (  0.332715)
832040.0
  0.330000   0.000000   0.330000 (  0.332331)

ruby-1.9.3-p0 ~/projects/jruby $ cast_off --run bench/bench_fib_float_recursive.rb 5 30832040.0
  0.220000   0.000000   0.220000 (  0.218369)
832040.0
  0.220000   0.000000   0.220000 (  0.221209)
832040.0
  0.220000   0.000000   0.220000 (  0.220458)
832040.0
  0.220000   0.000000   0.220000 (  0.217716)
832040.0
  0.250000   0.000000   0.250000 (  0.250451)

ruby-1.9.3-p0 ~/projects/jruby $ ruby -v bench/bench_fib_recursive.rb 5 30
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin10.8.0]
  0.180000   0.000000   0.180000 (  0.183686)
  0.180000   0.000000   0.180000 (  0.183474)
  0.190000   0.000000   0.190000 (  0.183440)
  0.180000   0.000000   0.180000 (  0.183403)
  0.180000   0.000000   0.180000 (  0.183839)

ruby-1.9.3-p0 ~/projects/jruby $ cast_off --run bench/bench_fib_recursive.rb 5 30
  0.060000   0.010000   0.070000 (  0.053983)
  0.050000   0.000000   0.050000 (  0.054199)
  0.050000   0.000000   0.050000 (  0.054230)
  0.050000   0.000000   0.050000 (  0.054481)
  0.060000   0.000000   0.060000 (  0.054941)

# JRuby still wins on both, but I'm not entirely sure why...

ruby-1.9.3-p0 ~/projects/jruby $ jruby bench/bench_fib_float_recursive.rb 10 30
832040.0
  0.185000   0.000000   0.185000 (  0.154000)
832040.0
  0.065000   0.000000   0.065000 (  0.065000)
832040.0
  0.056000   0.000000   0.056000 (  0.056000)
832040.0
  0.078000   0.000000   0.078000 (  0.078000)
832040.0
  0.041000   0.000000   0.041000 (  0.041000)
832040.0
  0.041000   0.000000   0.041000 (  0.041000)
832040.0
  0.042000   0.000000   0.042000 (  0.042000)
832040.0
  0.042000   0.000000   0.042000 (  0.042000)
832040.0
  0.042000   0.000000   0.042000 (  0.042000)
832040.0
  0.044000   0.000000   0.044000 (  0.044000)

ruby-1.9.3-p0 ~/projects/jruby $ jruby bench/bench_fib_recursive.rb 10 30
  0.126000   0.000000   0.126000 (  0.095000)
  0.032000   0.000000   0.032000 (  0.032000)
  0.033000   0.000000   0.033000 (  0.033000)
  0.033000   0.000000   0.033000 (  0.033000)
  0.032000   0.000000   0.032000 (  0.032000)
  0.032000   0.000000   0.032000 (  0.032000)
  0.033000   0.000000   0.033000 (  0.033000)
  0.032000   0.000000   0.032000 (  0.032000)
  0.032000   0.000000   0.032000 (  0.032000)
  0.032000   0.000000   0.032000 (  0.032000)

# CastOff does very well on tarai

ruby-1.9.3-p0 ~/projects/jruby $ ruby -v bm_app_tarai.rb 
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin10.8.0]
0.845492
0.845843
0.845498
0.843641
0.843561

ruby-1.9.3-p0 ~/projects/jruby $ cast_off --run bm_app_tarai.rb
0.053275
0.052842
0.053815
0.053394
0.053144

ruby-1.9.3-p0 ~/projects/jruby $ jruby bm_app_tarai.rb 20
0.23
0.118
0.119
0.118
0.118

# If we remove some guards from JRuby (Fixnum modification, result is Fixnum, overflow, self call method guards), it gets closer to CastOff
ruby-1.9.3-p0 ~/projects/jruby $ jruby bm_app_tarai.rb
0.145
0.081
0.086
0.084
0.081

# Remaining overhead may indicate inefficiencies in how JRuby's compiling this, obscuring some optimization potential from JVM.