measure.rb

require 'benchmark'

def measure(gc: false, times: 1000, &block)
  GC.start
  GC.disable if gc

  gc_key = if RUBY_VERSION > 2.2
    :total_allocated_objects
  else
    :total_allocated_object
  end

  memory_before = `ps -o rss= -p #{Process.pid}`.to_i
  objects_before = GC.stat(gc_key)

  runtime = Benchmark.realtime do
    times.times do
      yield
    end
  end

  object_delta = GC.stat(gc_key) - objects_before
  memory_delta = (`ps -o rss= -p #{Process.pid}`.to_i) - memory_before

  puts "Iterations: #{times}"
  puts "Runtime: #{runtime} :: #{runtime / times} per call"
  puts "Objects: #{object_delta} :: #{object_delta / times} per call"
  puts "Memory (RSS): #{memory_delta}KB"

  GC.enable
  GC.start
end