Brighton Ruby Conf 2014

Transcript

1. Hello!!!
2. Welcome!
3. Thanks!!!
4. You Beer Me
6. Samuel L. Jackson @tenderlove
8. America
9. 'MURICA
10. FREEDOM
13. Ruby Core Rails Core
14. Rack-Core Racc-Core
15. Psych-Core Fiddle-Core
16. Nokogiri-Core rails_autolink-Core
17. Core-Core IHaveNoIdea-Core
18. ☑Adequate Everything. Adequately.
19. Twitter: tenderlove GitHub: tenderlove Instagram: tenderlove Yo: tenderlove
20. ಠ_ಠ ಠ_ಠ Separation Of Concerns
21. OMG! INTERNET! POINTS
22. Revert Commits Count Too!
23. More mistakes == more points!!!!
24. Short Stack Engineer
27. Dad-Joke Programmer
28. Gorbachev Puff Puff Thunderhorse
29. SEA-TAC Airport YouTube
33. Node.JS
34. Closer to the METAL
36. ENGLAND!!
41. I realize
42. There is no "d" in "z".
43. "z" == "zee"
44. $$$$$$$$ $$$$$$$$ $$$ 'MURICA!
45. I feel very bad…
46. @fishermanchips
47. Brighton Ruby! Recap!
48. Ruby Order SORTED
49. Hi, I’m! Samuel L. Jackson!
50. Better Security
51. 255.255.255.254 Important!
52. Cucumber
53. Steak Holder
54. How to pick JS libraries
57. Quadrant System
58. Cats Code Beer Adequate System
59. 1 Quadrant Short.
60. It’s Adequate.
61. RubyMotion! is a bridge. (JUST KIDDING!)
62. My Favorite Type System
63. Word Perfect 5.1
64. Yo Dawg, I heard you like Sandi
66. Fizz Buzz?
67. I am not good enough to be a developer.
68. If I can developer, you can too!
69. BANANA!! ANANA!B
70. I’ve never played Mario Kart. :’(
71. Strong Ducks?
73. Gave me a run for my money.
74. Ground Breaking Technology
76. Speed up Rails,! Speed up your Code
77. Stuff on my mind
78. Pro Tip:
79. ruby -d
80. ruby -d -Ilib:test test/cases/ base_test.rb
81. Exception `LoadError' at rubygems.rb:1194 - cannot load such file -- rubygems/defaults/ operating_system ! Exception `LoadError' at kernel_require.rb:55 - cannot load such file -- bundler
82. Find Swallowed Exceptions!
83. Rack
84. def call(env) end LOL Global Data
85. There will be no Rack 2.0* * There will be a Rack 2.0
86. Ruby >= 2.0?
87. Next Generation
88. def call(env, input, output) end IO IO
89. Just Thoughts.
90. Performance Tools
91. Raw Performance
92. benchmark/ips
93. benchmark Benchmark.bm do |x| x.report('some test') { N.times { some_test } } end How big? STD LIB
94. Output user system total real some test 0.000000 0.000000 0.000000 ( 0.000098)
95. benchmark/ips require 'benchmark/ips' require 'set' ! list = ('a'..'zzzz').to_a set = Set.new list ! Benchmark.ips do |x| x.report("set access") { set.include? "foo" } ! x.report("ary access") { list.include? "foo" } end G EM
96. Output Calculating ------------------------------------- set access 68622 i/100ms ary access 395 i/100ms ------------------------------------------------- set access 3047175.3 (±12.7%) i/s - 14959596 in 5.018692s ary access 3899.2 (±7.1%) i/s - 19750 in 5.096118s IPS
97. Set Include: 3047175.3 / sec
98. Array Include: 3899.2 / sec
99. IPS: Higher Is Better
100. Output Calculating ------------------------------------- set access 68622 i/100ms ary access 395 i/100ms ------------------------------------------------- set access 3047175.3 (±12.7%) i/s - 14959596 in 5.018692s ary access 3899.2 (±7.1%) i/s - 19750 in 5.096118s STDDEV
101. benchmark N = 100000 ! list = ('a'..'zzz').to_a hash = list.each_with_object({}) { |x,h| h[x] = true } set = Set.new list ! Benchmark.bm do |x| x.report("set access") { N.times { set.include? "foo" } } ! x.report("hash access") { N.times { hash.include? "foo" } } end STD LIB
102. Output user system total real set access 0.030000 0.000000 0.030000 ( 0.030044) hash access 0.030000 0.000000 0.030000 ( 0.032125) Set Is Faster? benchm ark
103. benchmark/ips list = ('a'..'zzz').to_a hash = list.each_with_object({}) { |x,h| h[x] = true } set = Set.new list ! Benchmark.ips do |x| x.report("set access") { set.include? "foo" } x.report("hash access") { hash.include? "foo" } end G EM
104. Output Calculating ------------------------------------- set access 73910 i/100ms hash access 73845 i/100ms ------------------------------------------------- set access 3081455.6 (±7.6%) i/s - 15299370 in 4.999343s hash access 3772358.3 (±7.2%) i/s - 18756630 in 5.004747s benchm ark/ips
105. IPS Graph 0 1000000 2000000 3000000 4000000 Iterations / Sec Set access Hash Access
106. Blackbox Testing
107. Cache Impls cache1 = Cache1.new cache2 = Cache2.new ! cache1["x"] = Object.new cache2["x"] = Object.new ! Benchmark.ips do |x| x.report("cache1") { cache1["x"] } x.report("cache2") { cache2["x"] } end
108. Collect Reports reports = [10, 100, 1000, 100_000].map do |i| cache1 = Cache1.new cache2 = Cache2.new ! (i - 1).times { |z| cache2[z.to_s] = cache1[z.to_s] = Object.new } ! cache1["x"] = Object.new cache2["x"] = Object.new ! report = Benchmark.ips do |x| x.report("cache1") { cache1["x"] } x.report("cache2") { cache2["x"] } end [i, report] end Report
109. Compile Data header = nil rows = reports.map { |i,report| header ||= [nil] + report.map(&:label) ["#{i} elements"] + report.map { |r| (1 / r.ips) * 10_000 } } puts header.join ',' rows.each { |r| puts r.join ',' } Seconds Per Iteration Seconds for 10k iters
110. Runtime Graph Time for 10,000 iterations (seconds) 0.01 0.1 1 10 100 Cache Size 10 elements 100 elements 1000 elements 100000 elements Cache 1 Cache 2
111. Cache Implementation class Cache1 def initialize @cache = {} end def [] k; @cache[k]; end def []= k,v; @cache[k] = v; end end ! class Cache2 def initialize @cache = [] end def [] k; x, = @cache.assoc(k); x; end def []= k,v; @cache << [k, v]; end end Constant Linear
112. Real World Example: Routes
113. Number Of Routes class MyTest routes = ActionDispatch::Routing::RouteSet.new routes.draw { resources(:articles) } end ! article = Article.new.tap(&:save!) ! Benchmark.ips do |x| x.report("link_to") { test.link_to "zomg", article } end
114. Add 10 routes class MyTest routes = ActionDispatch::Routing::RouteSet.new routes.draw { resources(:articles) 10.times do |num| resources num.to_s.to_sym end } end
115. Add 100 routes class MyTest routes = ActionDispatch::Routing::RouteSet.new routes.draw { resources(:articles) 100.times do |num| resources num.to_s.to_sym end } end
116. Add 1000 routes class MyTest routes = ActionDispatch::Routing::RouteSet.new routes.draw { resources(:articles) 1000.times do |num| resources num.to_s.to_sym end } end
117. Sec / 100k calls 9.5 9.7 9.9 10.1 10.3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 link_to
118. Size of URL class MyTest routes = ActionDispatch::Routing::RouteSet.new link = 'a' ! routes.draw { get "/#{link}/:id", :as => :article, :controller => :articles, :action => :show } end ! test = MyTest.new article = Article.new.tap(&:save!) ! puts "Model Instance" Benchmark.ips do |x| x.report("link_to") { test.link_to "zomg", article } end
119. Length of 1 class MyTest routes = ActionDispatch::Routing::RouteSet.new link = 1.times.map(&:to_s).join '/' ! routes.draw { get "/#{link}/:id", :as => :article, :controller => :articles, :action => :show } end
120. Length of 10 class MyTest routes = ActionDispatch::Routing::RouteSet.new link = 10.times.map(&:to_s).join '/' ! routes.draw { get "/#{link}/:id", :as => :article, :controller => :articles, :action => :show } end
121. Length of 100 class MyTest routes = ActionDispatch::Routing::RouteSet.new link = 100.times.map(&:to_s).join '/' ! routes.draw { get "/#{link}/:id", :as => :article, :controller => :articles, :action => :show } end
122. Sec / 100k calls 9 10.5 12 13.5 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 link_to
123. Where is time spent?
124. stackprof https://github.com/tmm1/stackprof
125. Profiling url_for require 'stackprof' StackProf.run(mode: :cpu, out: 'url_for.dump') do 5000.times { test.url_for article } end
126. View Results $ stackprof url_for.dump --text
127. ================================== Mode: cpu(1000) Samples: 218 (0.00% miss rate) GC: 27 (12.39%) ================================== TOTAL (pct) SAMPLES (pct) FRAME 149 (68.3%) 57 (26.1%) ActionDispatch::Routing::RouteSet#url_for 183 (83.9%) 19 (8.7%) ActionDispatch::::UrlHelper#call 18 (8.3%) 18 (8.3%) #<Module:0x007fb2f4ea3db0>.build_host_url 14 (6.4%) 13 (6.0%) ActionDispatch::UrlHelper#handle_positional_args 68 (31.2%) 12 (5.5%) ActionDispatch::Journey::Formatter#generate 66 (30.3%) 12 (5.5%) ActionDispatch::Formatter#visit_CAT 10 (4.6%) 10 (4.6%) ActionDispatch::Utils::UriEncoder#escape 56 (25.7%) 7 (3.2%) block in ActionDispatch::Formatter#generate 13 (6.0%) 5 (2.3%) ActionDispatch#extract_parameterized_parts
128. GC.stat()
129. Total allocations GC.stat(:total_allocated_object)
130. Measure Allocations Person.find id before = GC.stat(:total_allocated_object) N.times { Person.find id } after = GC.stat(:total_allocated_object) puts (after - before) / N W arm up Benchmark Objects / Call Count O bjs C ount O bjs
131. Real World Example: Views
132. Request Benchmark task :allocated_objects do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) before = GC.stat :total_allocated_object TEST_CNT.times { do_test_task(app, env.dup) } after = GC.stat :total_allocated_object puts (after - before) / TEST_CNT end "/books/new"
133. Request Benchmark task :allocated_objects do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) before = GC.stat :total_allocated_object TEST_CNT.times { do_test_task(app, env.dup) } after = GC.stat :total_allocated_object puts (after - before) / TEST_CNT end
134. Request Benchmark task :allocated_objects do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) before = GC.stat :total_allocated_object TEST_CNT.times { do_test_task(app, env.dup) } after = GC.stat :total_allocated_object puts (after - before) / TEST_CNT end
135. Test Results Object Allocations Per Request 2000 2150 2300 2450 2600 4-0-stable 4-1-stable master 2000
136. HOW TO LIE WITH GRAPHS
137. Test Results Object Allocations Per Request 0 650 1300 1950 2600 4-0-stable 4-1-stable master
138. ~19% reduction since 4-0-stable
139. ~14% reduction since 4-1-stable
140. allocation_tracer https://github.com/ko1/allocation_tracer
141. Example ObjectSpace::AllocationTracer.trace do 1000.times { ["foo", {}] } end ! ObjectSpace::AllocationTracer.allocated_count_table
142. Output {:T_NONE=>0, :T_OBJECT=>0, :T_CLASS=>0, :T_MODULE=>0, :T_FLOAT=>0, :T_STRING=>1000, :T_REGEXP=>0, :T_ARRAY=>1000, :T_HASH=>1000, :T_ZOMBIE=>0}
143. Speeding up Helpers
144. Object Allocation Reduction
145. Profiling Request / Response
146. Test Code task :view_stack do app = Ko1TestApp::Application.instance app.app ! env = rackenv "/books/new" do_test_task(app, env.dup) require 'stackprof' puts "#" * 90 StackProf.run(mode: :cpu, out: 'req-res.dump') do 1800.times { do_test_task(app, env.dup) } end end
147. Test Code task :view_stack do app = Ko1TestApp::Application.instance app.app ! env = rackenv "/books/new" do_test_task(app, env.dup) require 'stackprof' puts "#" * 90 StackProf.run(mode: :cpu, out: 'req-res.dump') do 1800.times { do_test_task(app, env.dup) } end end
148. Test Code task :view_stack do app = Ko1TestApp::Application.instance app.app ! env = rackenv "/books/new" do_test_task(app, env.dup) require 'stackprof' puts "#" * 90 StackProf.run(mode: :cpu, out: 'req-res.dump') do 1800.times { do_test_task(app, env.dup) } end end
149. TOTAL (pct) SAMPLES (pct) FRAME 813 (9.5%) 813 (9.5%) ActiveSupport::SafeBuffer#initialize 699 (8.1%) 350 (4.1%) block in ActiveRecord::Read#read_attribute 486 (5.7%) 298 (3.5%) ActionController::UrlFor#url_options 670 (7.8%) 274 (3.2%) ActionDispatch::Journey::Format#evaluate 773 (9.0%) 253 (2.9%) ActionDispatch#parameterize_args 1172 (13.6%) 220 (2.6%) ActiveRecord::Persistence#instantiate 213 (2.5%) 213 (2.5%) block in SQLite3::Statement#each 208 (2.4%) 208 (2.4%) ActiveSupport::SafeBuffer#html_safe? 204 (2.4%) 204 (2.4%) ActionDispatch::UrlFor#routes_generation? 245 (2.9%) 191 (2.2%) block (2 levels) in Class#class_attribute
150. ActiveSupport::SafeBuffer #initialize
151. Finding Calls require 'active_support/all' ! trace = TracePoint.new(:c_call, :call) { |tp| if tp.defined_class == ActiveSupport::SafeBuffer && tp.method_id == :initialize puts "#" * 90 puts tp.binding.eval "caller" end } ! trace.enable "asdfadsf".html_safe ActiveSupport::SafeBuffer.new "omgee" Callstack
152. Output ##################################################################### t1.rb:7:in `eval' t1.rb:7:in `block in <main>' lib/active_support/core_ext/string/output_safety.rb:166:in `initialize' lib/active_support/core_ext/string/output_safety.rb:251:in `new' lib/active_support/core_ext/string/output_safety.rb:251:in `html_safe' t1.rb:12:in `<main>' ##################################################################### t1.rb:7:in `eval' t1.rb:7:in `block in <main>' lib/active_support/core_ext/string/output_safety.rb:166:in `initialize' t1.rb:13:in `new' t1.rb:13:in `<main>'
153. In Rails
154. Tag Options def tag_option(key, value, escape) if value.is_a?(Array) value = escape ? safe_join(value, " ") : value.join(" ") else value = escape ? ERB::Util.h(value) : value end %(#{key}="#{value}") end
155. HTML Sanitization in Rails
156. ActiveSupport:: SafeBuffer
157. Ordinary String >> x = "foo" => "foo" >> x.class => String >> x.html_safe? => false
158. SafeBuffer >> x = "foo" => "foo" >> y = x.html_safe => "foo" >> y.class => ActiveSupport::SafeBuffer >> y.html_safe? => true
159. `html_safe` just tags the string.
160. ERB::Utils.h
161. ERB::Utils.h def html_escape(s) s = s.to_s if s.html_safe? s else s.gsub(HTML_ESCAPE_REGEXP, HTML_ESCAPE).html_safe end end
162. Creates 2 Strings.
163. Tag Options def tag_option(key, value, escape) if value.is_a?(Array) value = escape ? safe_join(value, " ") : value.join(" ") else value = escape ? ERB::Util.h(value) : value end %(#{key}="#{value}") end
164. String -> String -> SafeBuffer -> String
165. String -> String -> String
166. Extract Method def unwrapped_html_escape(s) # :nodoc: s = s.to_s if s.html_safe? s else s.gsub(HTML_ESCAPE_REGEXP, HTML_ESCAPE) end end ! def html_escape(s) unwrapped_html_escape(s).html_safe end
167. Update Callers def tag_option(key, value, escape) if value.is_a?(Array) value = escape ? safe_join(value, " ") : value.join(" ") else value = escape ? ERB::Util.unwrapped_html_escape(value) : value end %(#{key}="#{value}") end
168. String -> String -> String
169. ~200 Allocations Per Request for /books/new
170. Request Benchmark task :allocation_tracer do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) ObjectSpace::AllocationTracer.trace do TEST_CNT.times { do_test_task(app, env.dup) } end p ObjectSpace::AllocationTracer.allocated_count_table end "/books/new"
171. Request Benchmark task :allocation_tracer do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) ObjectSpace::AllocationTracer.trace do TEST_CNT.times { do_test_task(app, env.dup) } end p ObjectSpace::AllocationTracer.allocated_count_table end
172. Request Benchmark task :allocation_tracer do app = Ko1TestApp::Application.instance app.app do_test_task(app) env = rackenv "/books/new" do_test_task(app, env.dup) ObjectSpace::AllocationTracer.trace do TEST_CNT.times { do_test_task(app, env.dup) } end p ObjectSpace::AllocationTracer.allocated_count_table end
173. Allocations Per Request 0 275 550 825 1100 T_STRING T_ARRAY T_HASH T_NODE T_DATA OTHER 4-0-stable 4-1-stable master
174. ~19% reduction since 4-0-stable
175. ~14% reduction since 4-1-stable
176. YMMV (Your Mileage (kilometers?) May Vary)
177. String Object Reduction
178. Mutable Strings irb(main):007:0> 5.times { irb(main):008:1* p "foo".object_id irb(main):009:1> } 70344882872020 70344882871920 70344882871840 70344882871720 70344882871540 => 5 irb(main):010:0>
179. Frozen Strings irb(main):010:0> 5.times { irb(main):011:1* p "foo".freeze.object_id irb(main):012:1> } 70344870307760 70344870307760 70344870307760 70344870307760 70344870307760 => 5
180. ERB Template <% books.each do |book| %> <tr><td> <%= book.name %> </tr></td> <% end %>
181. Compiled Template @output_buffer = output_buffer || ActionView::OutputBuffer.new;@output_buffer.safe_append='<h1>Listing books</h1> ! <table> <thead> <tr> <th>Name</th> <th colspan="3"></th> </tr> </thead> ! <tbody> '.freeze; @books.each do |book| @output_buffer.safe_append=' <tr> <td>'.freeze;@output_buffer.append=( book.name );@output_buffer.safe_append='</td> <td>'.freeze;@output_buffer.append=( link_to 'Show', book );@output_buffer.safe_append='</ td> </tr> '.freeze; end @output_buffer.safe_append=' </tbody> </table> ! <br>
182. Compiled Template @output_buffer = ActionView::OutputBuffer.new @output_buffer.safe_append=' <tr> <td>' @output_buffer.append=( book.name ) HTML Literal
183. Template Literals Can’t Change
184. Add `freeze` @output_buffer = ActionView::OutputBuffer.new @output_buffer.safe_append=' <tr> <td>’.freeze @output_buffer.append=( book.name ) HTML Literal
185. Allocations Per Request 0 275 550 825 1100 T_STRING T_ARRAY T_HASH T_NODE T_DATA OTHER 4-0-stable 4-1-stable master
186. Speeding up Output
187. WARNING:! Work in Progress
188. Law of Demeter
189. Suggestion of Demeter
191. Arrested Developer?
192. It’s not about dots, it’s about types.
193. Fewer Types == Faster / Easier code
194. Compiled Template @output_buffer = output_buffer || ActionView::OutputBuffer.new;@output_buffer.safe_append='<h1>Listing books</h1> ! <table> <thead> <tr> <th>Name</th> <th colspan="3"></th> </tr> </thead> ! <tbody> '.freeze; @books.each do |book| @output_buffer.safe_append=' <tr> <td>'.freeze;@output_buffer.append=( book.name );@output_buffer.safe_append='</td> <td>'.freeze;@output_buffer.append=( link_to 'Show', book );@output_buffer.safe_append='</ td> </tr> '.freeze; end @output_buffer.safe_append=' </tbody> </table> ! <br>
195. Compiled Template @output_buffer = ActionView::OutputBuffer.new @output_buffer.safe_append=' <tr> <td>'.freeze @output_buffer.append=( book.name ) HTML Literal
196. safe_append= class OutputBuffer def safe_append=(value) return self if value.nil? super(value.to_s) end end W hy?
197. safe_append= class OutputBuffer def safe_append=(value) super(value.to_s) end end
198. safe_append= class OutputBuffer def safe_append=(value) super(value) end end
199. safe_append= class OutputBuffer def safe_append=(value) super end end
200. safe_append= class OutputBuffer end
201. Law of Demeter
202. Defensive Programming
203. Limiting Types
204. "I only handle strings!"
205. superclass def safe_append=(value) (!html_safe? || arg.html_safe?) ? arg : ERB::Utils.h(arg) end Only on m utations
206. How can you get the Output Buffer?
207. Who Mutates the OutputBuffer?
208. I think no one.
209. superclass def safe_append=(value) arg.html_safe? ? arg : ERB::Utils.h(arg) end
210. Cache Invariants
211. Eliminate Objects
212. "No code is faster than no code"
213. Limit Types
214. Fewer Types = Less Code
215. Less Code = Faster Code
216. Report Performance Issues
217. Rails 4.2 will be the fastest ever!
218. THANKS!