Parsing ISO8601 Time format with Ruby

iso8601.rb

require 'time'
require 'benchmark'

time = Time.now.iso8601(3)
#  => "2014-05-26T23:26:08.628-07:00"

Benchmark.bm do |x|
  x.report('parse') { 100_000.times { Time.parse(time).gmtime } } 
  x.report('iso8601') { 100_000.times { Time.iso8601(time).gmtime } }
end

# MRI 2.1.2
#        user     system      total        real
# parse  2.890000   0.050000   2.940000 (  2.938882)
# iso8601  1.130000   0.010000   1.140000 (  1.144048)

# JRuby 1.7.12 (Stablized after a few runs)
#        user     system      total        real
# parse  4.810000   0.010000   4.820000 (  4.701000)
# iso8601  0.750000   0.000000   0.750000 (  0.715000)

joda.rb

require 'benchmark'
require 'logstash/event'

time = Time.now.iso8601(3)
# => "2014-05-26T23:35:53.961-07:00" 

Benchmark.bm do |x|
  x.report('joda') { 100_000.times { LogStash::Time.parse_iso8601(time) } } 
end

# JRuby 1.7.12 (Stabilized after a few runs)
#        user     system      total        real
# joda  0.230000   0.000000   0.230000 (  0.222000)

with JRuby use Benchmark.bmbm so it actually runs the benchmark twice, first as a"rehearsal" then the actual test so that the JVM gets warmed.

Oh interesting. I didn't know about that, thanks!

The results presented here are actually the "stablized" value after running the benchmarks a few times. I'll remember to use Benchmark.bmbm in the future to automate this!

I'll check this now and see if I get significantly different results.

I tried out Benchmark.bmbm and got similar results. I looked at this gist more closely and noticed that I did already put a comment in there: # JRuby 1.7.12 (Stabilized after a few runs)