each_vs_inject.rb

require 'benchmark/ips'

Benchmark.ips do |x|
  x.report("each") do
    s = 0
    (10 ** 5).times.each do |i|
      s += i
    end
  end

  x.report("inject") do
    (10 ** 5).times.inject(0) do |acc, i|
      acc + i
    end
  end

  x.compare!
end

result.txt

[15:23:20] ~ via 💎 v3.0.1
❯ ruby each_vs_inject.rb
Warming up --------------------------------------
                each    24.000  i/100ms
              inject    16.000  i/100ms
Calculating -------------------------------------
                each    227.144  (± 3.5%) i/s -      1.152k in   5.078252s
              inject    137.510  (± 9.5%) i/s -    688.000  in   5.052515s

Comparison:
                each:      227.1 i/s
              inject:      137.5 i/s - 1.65x  (± 0.00) slower