gistfile1.txt

Calculating -------------------------------------
            Array#[]   201.052k i/100ms
            Array#at   194.228k i/100ms
-------------------------------------------------
            Array#[]     11.090M (± 2.2%) i/s -     55.490M
            Array#at     10.003M (± 1.3%) i/s -     50.111M

Comparison:
            Array#[]: 11089538.6 i/s
            Array#at: 10002944.7 i/s - 1.11x slower

webscale.rb

require 'benchmark/ips'

array = (1..1_000_000).to_a

Benchmark.ips do |bench|
  bench.report 'Array#[]' do
    array[4]
  end

  bench.report 'Array#at' do
    array.at(4)
  end

  bench.compare!
end