Commits on Mar 5, 2014

1. only loop over spec dependencies to resolve conflicts …

   Before this commit, the `conflicts` method would loop over every
   activated gem and the `conflicts` method would get slower as you
   activate more gems.
   
   This commit speeds up the `conflicts` method which is called on ever gem
   activation by only looping over dependencies on the spec itself, then
   looking up possible conflicts from the loaded_specs hash.
   
   Here is the benchmark:
   
   ```ruby
   def util_spec name, version = 2
     spec = Gem::Specification.new do |s|
       s.platform    = Gem::Platform::RUBY
       s.name        = name
       s.version     = version
       s.author      = 'A User'
       s.email       = 'example@example.com'
       s.homepage    = 'http://example.com'
       s.summary     = "this is a summary"
       s.description = "This is a test description"
     end
   
     spec.loaded_from = spec.spec_file
   
     Gem::Specification.add_spec spec
   
     return spec
   end
   
   require 'benchmark/ips'
   
   (ENV['N'] || 100).to_i.times { |i| util_spec(i.to_s).activate }
   
   p Gem.loaded_specs.size
   
   Benchmark.ips do |x|
     spec = util_spec 'a'
     # Typical mode, runs the block as many times as it can
     x.report("conflicts") { spec.conflicts }
   end
   ```
   
   Before my change:
   
   ```
   [aaron@higgins rubygems (master)]$ N=100 ruby -I lib test.rb
   101
   Calculating -------------------------------------
              conflicts      1957 i/100ms
   -------------------------------------------------
              conflicts    20090.1 (±4.6%) i/s -     101764 in   5.077002s
   [aaron@higgins rubygems (master)]$ N=1000 ruby -I lib test.rb
   1001
   Calculating -------------------------------------
              conflicts       214 i/100ms
   -------------------------------------------------
              conflicts     2209.6 (±5.0%) i/s -      11128 in   5.050977s
   ```
   
   After my change:
   
   ```
   [aaron@higgins rubygems (master)]$ N=100 ruby -I lib test.rb
   101
   Calculating -------------------------------------
              conflicts     71357 i/100ms
   -------------------------------------------------
              conflicts  2230414.4 (±7.2%) i/s -   11131692 in   5.022458s
   [aaron@higgins rubygems (master)]$ N=1000 ruby -I lib test.rb
   1001
   Calculating -------------------------------------
              conflicts     69479 i/100ms
   -------------------------------------------------
              conflicts  2171237.1 (±6.2%) i/s -   10838724 in   5.013410s
   ```
   
   You can see that after this change the speed of `conflicts` stays about
   the same regardless of the number of specs loaded.

   

   tenderlove committed Mar 5, 2014
   Configuration menu

   • View commit details
   • Copy full SHA for 3e6cd47
   • Browse repository at this point

   Copy the full SHA

   3e6cd47 View commit details

   Browse the repository at this point in the history