Benchmarking generating fairly unique tokens quickly without external dependencies

quick_token.rb

require 'benchmark'

Benchmark.bmbm do |x|
  x.report('printf') do
    for i in 1..1_000_000
      3.times.map { '%06x' % rand(0x100000) }.join
    end
  end

  x.report('to_s') do
    for i in 1..1_000_000
      3.times.map { rand(0x100000).to_s(36) }.join
    end
  end
end

# Rehearsal ------------------------------------------
# printf   8.580000   0.020000   8.600000 (  8.597337)
# to_s     3.010000   0.000000   3.010000 (  3.019717)
# -------------------------------- total: 11.610000sec
# 
#              user     system      total        real
# printf   8.560000   0.020000   8.580000 (  8.584776)
# to_s     3.040000   0.000000   3.040000 (  3.039551)