Benchmarking sort strategies in Ruby.

bench-sort.rb

require 'benchmark'

a = Array.new(10_000) { rand }

Benchmark.bm(20) do |bench|
  bench.report('sort <=>') { 10.times { a.sort { |x,y| y <=> x } } }
  bench.report('sort.reverse') { 10.times { a.sort.reverse } }
  bench.report('sort_by.reverse') { 10.times { a.sort_by(&:to_f).reverse } }
end

#                            user     system      total        real
# sort <=>               0.130000   0.000000   0.130000 (  0.131826)
# sort.reverse           0.070000   0.000000   0.070000 (  0.066339)
# sort_by.reverse        0.070000   0.000000   0.070000 (  0.070748)