Ruby string interpolation bench: annotated vs unannotated (http://rubocop.readthedocs.io/en/latest/cops_style/#styleformatstringtoken)

bench.rb

#!/usr/bin/env ruby
require 'benchmark/ips'
require 'bundler/setup'
require 'dnsimple'

account_id = 1010
zone_id    = 100
record_id  = 999

Benchmark.ips do |x|
  x.report("unannotated") { Dnsimple::Client.versioned("/%s/zones/%s/records/%s" % [account_id, zone_id, record_id]) }
  x.report("annotated")   { Dnsimple::Client.versioned("/%<account_id>s/zones/%<zone_id>s/records/%<record_id>s" % {account_id: account_id, zone_id: zone_id, record_id: record_id}) }
  x.compare!
end

__END__
Result:

  Warming up --------------------------------------
           unannotated    40.723k i/100ms
             annotated    29.192k i/100ms
  Calculating -------------------------------------
           unannotated    469.618k (± 2.8%) i/s -      2.362M in   5.033355s
             annotated    312.024k (± 4.5%) i/s -      1.576M in   5.062552s

  Comparison:
           unannotated:   469618.4 i/s
             annotated:   312023.6 i/s - 1.51x  slower

Ruby:

    ruby 2.4.2p198 (2017-09-14 revision 59899) [x86_64-darwin16]

Hardware:

    Hardware Overview:

      Model Name: MacBook Pro
      Model Identifier: MacBookPro12,1
      Processor Name: Intel Core i7
      Processor Speed: 3,1 GHz
      Number of Processors: 1
      Total Number of Cores: 2
      L2 Cache (per Core): 256 KB
      L3 Cache: 4 MB
      Memory: 16 GB
      Boot ROM Version: MBP121.0171.B00
      SMC Version (system): 2.28f7

Software:

    System Software Overview:

      System Version: macOS 10.12.6 (16G1114)
      Kernel Version: Darwin 16.7.0
      Time since boot: 10 days 6:49