benchpress.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin
Date: February 06, 2011
Summary: Comparing Nokogiri's parsers

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i7 2.66 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH" is up to 16% faster over 1,000 repetitions

Nokogiri XPATH                0.13944482803344727 secs    Fastest
Nokogiri Search (w/ XPATH)    0.14812183380126953 secs    5% Slower
Nokogiri CSS                  0.16048192977905273 secs    13% Slower
Nokogiri Search (w/ CSS)      0.16649389266967773 secs    16% Slower

benchpress_10000reps_01.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin - Ian D. Eccles
Date: February 07, 2011
Summary: Comparing Nokogiri's parsers and RegEx for good measure.

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i5 2.53 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH - /html/head/title" is up to 64% faster over 10,000 repetitions

Nokogiri XPATH - /html/head/title                0.5199141502380371 secs    Fastest
Nokogiri Search (w/ XPATH) - /html/head/title    0.6333937644958496 secs    17% Slower
Nokogiri XPATH - //head/title                    1.1117651462554932 secs    53% Slower
Nokogiri XPATH - //title                         1.129045009613037  secs    53% Slower
Nokogiri Search (w/ XPATH) - //title             1.2313289642333984 secs    57% Slower
Nokogiri Search (w/ XPATH) - //head/title        1.2370507717132568 secs    57% Slower
Nokogiri Search (w/ CSS) - title                 1.3102619647979736 secs    60% Slower
Nokogiri CSS - title                             1.3113257884979248 secs    60% Slower
Nokogiri CSS - head title                        1.318915843963623  secs    60% Slower
Nokogiri CSS - title                             1.3250529766082764 secs    60% Slower
Nokogiri Search (w/ CSS) - head>title            1.3271639347076416 secs    60% Slower
Nokogiri Search (w/ CSS) - title                 1.3291771411895752 secs    60% Slower
Nokogiri CSS - head>title                        1.3403031826019287 secs    61% Slower
Nokogiri Search (w/ CSS) - head title            1.356755018234253  secs    61% Slower
Nokogiri Search (w/ CSS) - html>head>title       1.380044937133789  secs    62% Slower
Nokogiri CSS - html>head>title                   1.415450096130371  secs    63% Slower
Nokogiri CSS - html head title                   1.455049991607666  secs    64% Slower
Nokogiri Search (w/ CSS) - html head title       1.4604699611663818 secs    64% Slower

benchpress_10000reps_02.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin - Ian D. Eccles
Date: February 07, 2011
Summary: Comparing Nokogiri's parsers and RegEx for good measure.

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i5 2.53 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH - /html/head/title" is up to 65% faster over 10,000 repetitions

Nokogiri XPATH - /html/head/title                0.549346923828125  secs    Fastest
Nokogiri Search (w/ XPATH) - /html/head/title    0.6463708877563477 secs    15% Slower
Nokogiri XPATH - //title                         1.1517019271850586 secs    52% Slower
Nokogiri XPATH - //head/title                    1.1620349884033203 secs    52% Slower
Nokogiri Search (w/ XPATH) - //head/title        1.291672945022583  secs    57% Slower
Nokogiri Search (w/ XPATH) - //title             1.3146800994873047 secs    58% Slower
Nokogiri CSS - title                             1.3669140338897705 secs    59% Slower
Nokogiri Search (w/ CSS) - head title            1.3699350357055664 secs    59% Slower
Nokogiri CSS - head title                        1.3751940727233887 secs    60% Slower
Nokogiri Search (w/ CSS) - title                 1.3816111087799072 secs    60% Slower
Nokogiri CSS - title                             1.3922057151794434 secs    60% Slower
Nokogiri Search (w/ CSS) - title                 1.3927769660949707 secs    60% Slower
Nokogiri CSS - head>title                        1.430954933166504  secs    61% Slower
Nokogiri Search (w/ CSS) - head>title            1.438581943511963  secs    61% Slower
Nokogiri Search (w/ CSS) - html>head>title       1.4586009979248047 secs    62% Slower
Nokogiri CSS - html>head>title                   1.4640250205993652 secs    62% Slower
Nokogiri CSS - html head title                   1.5587737560272217 secs    64% Slower
Nokogiri Search (w/ CSS) - html head title       1.5759928226470947 secs    65% Slower

benchpress_more.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin
Date: February 06, 2011
Summary: Comparing Nokogiri's parsers

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i7 2.66 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH - Specific" is up to 74% faster over 1,000 repetitions

Nokogiri XPATH - Specific                     0.04272198677062988  secs    Fastest
Nokogiri Search (w/ XPATH) - Specific         0.051782846450805664 secs    17% Slower
Nokogiri XPATH - Semi-Specific                0.1356217861175537   secs    68% Slower
Nokogiri XPATH - Nonspecific                  0.14063310623168945  secs    69% Slower
Nokogiri CSS - Nonspecific                    0.1483469009399414   secs    71% Slower
Nokogiri Search (w/ CSS) - Nonspecific        0.15012288093566895  secs    71% Slower
Nokogiri Search (w/ CSS) - Semi-Specific      0.15072989463806152  secs    71% Slower
Nokogiri CSS - Semi-Specific                  0.15105509757995605  secs    71% Slower
Nokogiri Search (w/ XPATH) - Semi-Specific    0.15113496780395508  secs    71% Slower
Nokogiri Search (w/ XPATH) - Nonspecific      0.1534569263458252   secs    72% Slower
Nokogiri Search (w/ CSS) - Specific           0.16422104835510254  secs    73% Slower
Nokogiri CSS - Specific                       0.1705338954925537   secs    74% Slower

benchpress_more_specific.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin - Ian D. Eccles
Date: February 07, 2011
Summary: Comparing Nokogiri's parsers and RegEx for good measure.

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i5 2.53 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH - Specific" is up to 67% faster over 1,000 repetitions

Nokogiri XPATH - Specific                     0.05413079261779785 secs    Fastest
Nokogiri Search (w/ XPATH) - Specific         0.06922698020935059 secs    21% Slower
Nokogiri XPATH - Semi-Specific                0.11409807205200195 secs    52% Slower
Nokogiri XPATH - Nonspecific                  0.11448025703430176 secs    52% Slower
Nokogiri Search (w/ XPATH) - Semi-Specific    0.12456512451171875 secs    56% Slower
Nokogiri Search (w/ CSS) - Semi-Specific      0.1319267749786377  secs    58% Slower
Nokogiri Search (w/ CSS) - Nonspecific        0.13361787796020508 secs    59% Slower
Nokogiri CSS - More Specific                  0.1415722370147705  secs    61% Slower *
Nokogiri CSS - Nonspecific                    0.141798734664917   secs    61% Slower
Nokogiri CSS - Semi-Specific                  0.1418309211730957  secs    61% Slower
Nokogiri Search (w/ CSS) - More Specific      0.1437239646911621  secs    62% Slower *
Nokogiri Search (w/ XPATH) - Nonspecific      0.14478492736816406 secs    62% Slower
Nokogiri Search (w/ CSS) - Specific           0.15114283561706543 secs    64% Slower
Nokogiri CSS - Specific                       0.1663680076599121  secs    67% Slower

benchpress_more_specific_02.md

Nokogiri Parser Comparisons

Author: Ezekiel Templin - Ian D. Eccles
Date: February 07, 2011
Summary: Comparing Nokogiri's parsers and RegEx for good measure.

System Information

Operating System:    Mac OS X 10.6.6 (10J567)
CPU:                 Intel Core i5 2.53 GHz
Processor Count:     2
Memory:              4 GB
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-darwin10.6.0]

"Nokogiri XPATH - /html/head/title" is up to 60% faster over 1,000 repetitions

Nokogiri XPATH - /html/head/title                0.05964303016662598 secs    Fastest
Nokogiri Search (w/ XPATH) - /html/head/title    0.06176280975341797 secs    3% Slower
Nokogiri XPATH - //title                         0.11733198165893555 secs    49% Slower
Nokogiri XPATH - //head/title                    0.11788702011108398 secs    49% Slower
Nokogiri Search (w/ XPATH) - //head/title        0.12118005752563477 secs    50% Slower
Nokogiri Search (w/ XPATH) - //title             0.1237180233001709  secs    51% Slower
Nokogiri CSS - title                             0.12938594818115234 secs    53% Slower
Nokogiri Search (w/ CSS) - title                 0.1294267177581787  secs    53% Slower
Nokogiri Search (w/ CSS) - head title            0.12976598739624023 secs    54% Slower
Nokogiri Search (w/ CSS) - head>title            0.1303880214691162  secs    54% Slower
Nokogiri CSS - head>title                        0.13044309616088867 secs    54% Slower
Nokogiri CSS - head title                        0.13219928741455078 secs    54% Slower
Nokogiri CSS - title                             0.13598322868347168 secs    56% Slower
Nokogiri Search (w/ CSS) - title                 0.13603901863098145 secs    56% Slower
Nokogiri Search (w/ CSS) - html>head>title       0.1388840675354004  secs    57% Slower
Nokogiri CSS - html head title                   0.14284586906433105 secs    58% Slower
Nokogiri Search (w/ CSS) - html head title       0.14297819137573242 secs    58% Slower
Nokogiri CSS - html>head>title                   0.15062904357910156 secs    60% Slower

nokogiri-parsers.rb

require 'nokogiri'
require 'bench_press'
extend BenchPress

name 'Nokogiri Parser Comparisons'
author 'Ezekiel Templin'
date '2011-02-06'
summary 'Comparing Nokogiri\'s parsers'

@doc = Nokogiri::HTML.parse(open('test.html'))

measure "Nokogiri CSS" do
  @doc.css('title')
end

measure "Nokogiri XPATH" do
  @doc.xpath('//title')
end

measure "Nokogiri Search (w/ XPATH)" do
  @doc.search('//title')
end

measure "Nokogiri Search (w/ CSS)" do
  @doc.search('title')
end

nokogiri-parsers_more.rb

require 'nokogiri'
require 'bench_press'
extend BenchPress

name 'Nokogiri Parser Comparisons'
author 'Ezekiel Templin'
date '2011-02-06'
summary 'Comparing Nokogiri\'s parsers and RegEx for good measure.'
@file = File.open('test.html', 'r')

@xpath_non = "//title"
@xpath_semi = "//head/title"
@xpath_spec = "/html/head/title"

@css_non = "title"
@css_semi = "head title"
@css_spec = "html head title"
@css_spec_more = "html > head > title"

@doc = Nokogiri::HTML.parse(@file)

# XPath

measure "Nokogiri XPATH - Nonspecific" do
  @doc.xpath(@xpath_non)
end

measure "Nokogiri Search (w/ XPATH) - Nonspecific" do
  @doc.search(@xpath_non)
end

measure "Nokogiri XPATH - Semi-Specific" do
  @doc.xpath(@xpath_semi)
end

measure "Nokogiri Search (w/ XPATH) - Semi-Specific" do
  @doc.search(@xpath_semi)
end

measure "Nokogiri XPATH - Specific" do
  @doc.xpath(@xpath_spec)
end

measure "Nokogiri Search (w/ XPATH) - Specific" do
  @doc.search(@xpath_spec)
end

# CSS

measure "Nokogiri CSS - Nonspecific" do
  @doc.css(@css_non)
end

measure "Nokogiri Search (w/ CSS) - Nonspecific" do
  @doc.search(@css_non)
end

measure "Nokogiri CSS - Semi-Specific" do
  @doc.css(@css_semi)
end

measure "Nokogiri Search (w/ CSS) - Semi-Specific" do
  @doc.search(@css_semi)
end

measure "Nokogiri CSS - Specific" do
  @doc.css(@css_spec)
end

measure "Nokogiri CSS - More Specific" do
  @doc.css(@css_spec_more)
end

measure "Nokogiri Search (w/ CSS) - Specific" do
  @doc.search(@css_spec)
end

measure "Nokogiri Search (w/ CSS) - More Specific" do
  @doc.search(@css_spec_more)
end

What's interesting to me is how different the results can be between runs. Compare https://gist.github.com/814429#file_benchpress_more_specific_02.md and https://gist.github.com/814429#file_benchpress_more_specific.md. Same tests are being run, but suddenly the "html>head>title" selector becomes the slowest. There seems to be a lot of variability in the performance of CSS selectors that I wouldn't expect.

CSS is definitely getting smoked by XPath, there's no question of that. Maybe more than 1000 iterations need to be run to get more stable results amongst the other searches?