From f70987ccde6f14d4ac17c29cd2d3cd4d8b4f6846 Mon Sep 17 00:00:00 2001
From: Antonio Terceiro <terceiro@colivre.coop.br>
Date: Mon, 9 Aug 2010 18:14:59 -0300
Subject: [PATCH] Adding a performance test for blog display

---
 test/integration/performance_test.rb | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+), 0 deletions(-)
 create mode 100644 test/integration/performance_test.rb

diff --git a/test/integration/performance_test.rb b/test/integration/performance_test.rb
new file mode 100644
index 0000000..a25f43d
--- /dev/null
+++ b/test/integration/performance_test.rb
@@ -0,0 +1,64 @@
+require "#{File.dirname(__FILE__)}/../test_helper"
+require 'benchmark'
+
+class PerformanceTest < ActionController::IntegrationTest
+
+  all_fixtures
+
+  # Testing blog page display. It should not present a linear increase in time
+  # needed to display a blog page with the increase in number of posts.
+  #
+  # GOOD          BAD
+  #  
+  # ^             ^     /
+  # |             |    /
+  # |   _____     |   /
+  # |  /          |  /
+  # | /           | /
+  # |/            |/
+  # +--------->   +--------->
+  # 0  50  100    0  50  100
+  #
+  should 'not have a linear increase in time to display a blog page' do
+    person = create_profile('clueless')
+
+    # no posts
+    time0 = (Benchmark.measure { get '/clueless/blog' })
+
+    # first 50
+    create_posts(person)
+    time1 = (Benchmark.measure { get '/clueless/blog' })
+
+    # another 50
+    create_posts(person)
+    time2 = (Benchmark.measure { get '/clueless/blog' })
+
+    # should not scale linearly, i.e. the inclination of the first segment must
+    # be a lot higher than the one of the segment segment. To compensate for
+    # small variations due to hardware and/or execution environment, we are
+    # satisfied if the the inclination of the first segment is at least twice
+    # the inclination of the second segment.
+    a1 = (time1.total - time0.total)/50.0
+    a2 = (time2.total - time1.total)/50.0
+    assert a1 > a2*2, "#{a1} should be larger than #{a2} by at least a factor of 2"
+  end
+
+  protected
+
+  def create_profile(name)
+    person = create_user(name).person
+    Blog.create(:name => "Blog", :profile => person)
+    person
+  end
+
+  def create_posts(profile)
+    postnumber = profile.articles.count
+    blog = profile.blog
+    50.times do |i|
+      postnumber += 1
+      TinyMceArticle.create!(:profile => profile, :parent => blog, :name => "post number #{postnumber}")
+    end
+  end
+
+end
+
--
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