2.4-bench.rb

require 'benchmark/ips'

def class_integer
  0.class == Integer
end

def version_gte
  RUBY_VERSION >= '2.4'
end

Benchmark.ips do |x|
  x.report("0.class == Integer") { class_integer }
  x.report("RUBY_VERSION") { version_gte }
  x.compare!
end

__END__

Warming up --------------------------------------
  0.class == Integer   255.499k i/100ms
        RUBY_VERSION   209.773k i/100ms
Calculating -------------------------------------
  0.class == Integer      7.971M (± 5.6%) i/s -     39.858M in   5.016829s
        RUBY_VERSION      4.997M (± 3.7%) i/s -     25.173M in   5.044146s

Comparison:
  0.class == Integer:  7970583.6 i/s
        RUBY_VERSION:  4997419.2 i/s - 1.59x  slower