Benchmark rubygems list implementations

benchmark_rubygems_list.rb

# A benchmarking script for Rubygems' linked list implementation.
# See https://github.com/rubygems/rubygems/pull/1200
#
# To run, clone the rubygems repo and place this file in the
# root of the checkout. Then run:
#
#     ruby ./benchmark_rubygems_list.rb
#
require 'benchmark'
require './lib/rubygems/util/list.rb'

git_branch_name = `git rev-parse --abbrev-ref HEAD`.chomp
puts "\n#{'=' * 50}\nBenchmarking Gem::List in git branch #{git_branch_name}\n#{'=' * 50}\n\n"

NUM_LISTS = 1000
LIST_SIZE = 1000
NUM_TIMES =  100

lists = Array.new(NUM_LISTS) { (0...LIST_SIZE).inject(nil) { |l, v| Gem::List.prepend(l, v) } }

Benchmark.bmbm do |x|
  x.report("#{git_branch_name} to_a:") { NUM_TIMES.times { lists.map { |l| l.to_a } } }
  x.report("#{git_branch_name} find:") { NUM_TIMES.times { lists.map { |l| l.find { |v| v < 0 } } } }
end

results.txt

$ git co master
$ ruby ./benchmark_rubygems_list.rb

==================================================
Benchmarking Gem::List in git branch master
==================================================

Rehearsal ------------------------------------------------
master to_a:  12.060000   0.170000  12.230000 ( 12.245445)
master find:  12.110000   0.010000  12.120000 ( 12.127869)
-------------------------------------- total: 24.350000sec

                   user     system      total        real
master to_a:  11.090000   0.130000  11.220000 ( 11.227482)
master find:  11.720000   0.010000  11.730000 ( 11.736898)

$ git co more-dry-list
Switched to branch 'more-dry-list'
Your branch is up-to-date with 'origin/more-dry-list'.
msiegel@nantucket:~/Documents/workspace/OpenSource/rubygems$ ruby ./benchmark_rubygems_list.rb

==================================================
Benchmarking Gem::List in git branch more-dry-list
==================================================

Rehearsal -------------------------------------------------------
more-dry-list to_a:   8.350000   0.280000   8.630000 (  8.639509)
more-dry-list find:  11.330000   0.030000  11.360000 ( 11.363005)
--------------------------------------------- total: 19.990000sec

                          user     system      total        real
more-dry-list to_a:   8.030000   0.240000   8.270000 (  8.273676)
more-dry-list find:  11.710000   0.020000  11.730000 ( 11.726015)