require 'benchmark/ips'

arr = (1..100).to_a
Benchmark.ips do |x|
  x.report("Stack") { arr.push arr.pop }
  x.report("Tail -> Head Queue") { arr.unshift arr.pop }
  x.report("Head -> Tail Queue (shift)") { arr.push arr.shift }
  x.report("Head -> Tail Queue (delete_at)") { arr.push arr.delete_at(0) }
end

               Stack           4.994M (± 0.2%) i/s -     24.985M
  Tail -> Head Queue           5.092M (± 0.1%) i/s -     25.521M
Head -> Tail Queue (shift)     4.898M (± 0.1%) i/s -     24.511M
Head -> Tail Queue (delete_at) 4.453M (± 0.1%) i/s -     22.289M