Micro-benchmarking different error handling methods in ruby

bench_error_handling.rb

# frozen_string_literal: true

# Some, probable not extreamly clever, micro benchmarks to compare
# different methods of "return a value or error".
# The samples benchmark the error path only.

require 'benchmark/ips'
require 'dry/monads/result'

M = Dry::Monads
Result = Struct.new(:success, :value)

def _return_nil; nil end
def _return_failure; M.Failure("error") end
def _return_struct; Result.new(false, "error") end
def _raise_error; raise StandardError, "error" end
def _throw_error; throw(:test, "error") end

def fastest
  result = _return_nil
  result if result
end

def medium
  result = catch(:test) { _throw_error }
  result
end

def slow
  result = begin
    _raise_error
  rescue StandardError => e
    nil
  end
  result
end

def dry_failure
  result = _return_failure
  result.value_or(nil)
end

def result_struct
  result = _return_struct
  result.success ? result.value : nil
end

Benchmark.ips do |x|
  x.warmup = 100

  x.report('return') { fastest }
  x.report('throw')  { medium }
  x.report('raise')  { slow }

  x.report('Failure()') { dry_failure }
  x.report('Struct') { result_struct }

  x.compare!
end

###
# macOS 10.14.1
# Intel(R) Core(TM) i7-4980HQ CPU @ 2.80GHz
# 16GB RAM
# Lots of background noise
###
#
# ruby 2.6.0preview3 (2018-11-06 trunk 65578) [x86_64-darwin18]
# raise_vs_return.rb:28: warning: assigned but unused variable - e
# Calculating -------------------------------------
#               return   207.114k i/100ms
#                throw   143.958k i/100ms
#                raise    74.611k i/100ms
#            Failure()    38.082k i/100ms
#               Struct   149.491k i/100ms
# -------------------------------------------------
#               return     14.433M (± 4.2%) i/s -     72.076M
#                throw      3.772M (± 3.1%) i/s -     18.858M
#                raise      1.121M (± 4.7%) i/s -      5.596M
#            Failure()    472.264k (± 3.4%) i/s -      2.361M
#               Struct      4.539M (± 3.2%) i/s -     22.723M
#
# Comparison:
#               return: 14433477.6 i/s
#               Struct:  4538907.4 i/s - 3.18x slower
#                throw:  3771951.7 i/s - 3.83x slower
#                raise:  1120595.5 i/s - 12.88x slower
#            Failure():   472264.2 i/s - 30.56x slower
#
###
#
# ruby --jit -v raise_vs_return.rb
# ruby 2.6.0preview3 (2018-11-06 trunk 65578) +JIT [x86_64-darwin18]
# raise_vs_return.rb:28: warning: assigned but unused variable - e
# Calculating -------------------------------------
#               return   224.228k i/100ms
#                throw   148.997k i/100ms
#                raise    75.438k i/100ms
#            Failure()    38.648k i/100ms
#               Struct   164.680k i/100ms
# -------------------------------------------------
#               return     24.915M (± 4.6%) i/s -    124.222M
#                throw      3.983M (± 6.3%) i/s -     19.817M
#                raise      1.139M (± 3.0%) i/s -      5.733M
#            Failure()    485.783k (± 6.4%) i/s -      2.435M
#               Struct      5.195M (± 6.0%) i/s -     25.855M
#
# Comparison:
#               return: 24914915.7 i/s
#               Struct:  5194806.9 i/s - 4.80x slower
#                throw:  3982539.1 i/s - 6.26x slower
#                raise:  1139278.3 i/s - 21.87x slower
#            Failure():   485783.5 i/s - 51.29x slower
#
###
#
# jruby 9.2.4.1 (2.5.0) 2018-11-28 f487d1e Java HotSpot(TM) 64-Bit Server VM 25.60-b23 on 1.8.0_60-b27 +jit [darwin-x86_64]
# Calculating -------------------------------------
#              return   148.276k i/100ms
#               throw    52.078k i/100ms
#               raise     1.389k i/100ms
#           Failure()     1.294k i/100ms
#              Struct   113.227k i/100ms
# -------------------------------------------------
#              return     18.470M (± 7.6%) i/s -     91.486M
#               throw    917.148k (± 2.9%) i/s -      4.583M
#               raise     14.407k (± 3.6%) i/s -     72.228k
#           Failure()     13.793k (± 2.1%) i/s -     69.876k
#              Struct      6.767M (± 4.0%) i/s -     33.742M
#
# Comparison:
#              return: 18469948.6 i/s
#              Struct:  6767455.3 i/s - 2.73x slower
#               throw:   917147.5 i/s - 20.14x slower
#               raise:    14407.3 i/s - 1281.99x slower
#           Failure():    13793.2 i/s - 1339.06x slower#