strings_vs_symbol_benchmark.rb

require 'benchmark/ips'

str = { "foo" => 1 }
sym = { foo: 1 }

Benchmark.ips do |x|
  x.report("string") { str["foo"] }
  x.report("symbol") { sym[:foo]  }

  x.compare!
end

#### Results (Ruby 2.4) ####
# Warming up --------------------------------------
#               string   153.784k i/100ms
#               symbol   180.471k i/100ms
# Calculating -------------------------------------
#               string      5.493M (± 3.2%) i/s -     27.527M in   5.016529s
#               symbol      9.323M (± 3.8%) i/s -     46.562M in   5.001791s
#
# Comparison:
#               symbol:  9323414.3 i/s
#               string:  5493159.4 i/s - 1.70x  slower