Benchmark 可以用来测试某个函数或者任何代码的执行时间。

用法很简单：

require 'benchmark'
n = 1500
Benchmark.bmbm do |x|
  x.report("+ method") { n.times {string1 = "ddd" + "11111" + "Helodd" } }
  x.report("<< method") { n.times {string2 = "ddd" << "11111" << "Helodd"} }
end

结果如下：

usermatoMacBook-Pro:test qichunren$ ruby test.rb
Rehearsal ---------------------------------------------
+ method    0.000000   0.000000   0.000000 (  0.001722)
<< method   0.000000   0.000000   0.000000 (  0.001073)
------------------------------------ total: 0.000000sec

                user     system      total        real
+ method    0.000000   0.000000   0.000000 (  0.001040)
<< method   0.000000   0.000000   0.000000 (  0.000719)

参考资料