tt1

.gitignore

Gemfile.lock

Gemfile

source :rubygems
gem 'activerecord', '~>3.2'
gem 'pg'

test.rb

require 'rubygems'
require 'bundler/setup'
require 'active_record'

conn = {:adapter => 'postgresql', :database => "tt_test", :pool => 30, :allow_concurrency => true}
`dropdb tt_test`
`createdb tt_test`

ActiveRecord::Base.establish_connection conn
ActiveRecord::Migration.create_table(:bla){|t| t.integer :a; t.string :b }
class Bla < ActiveRecord::Base; self.table_name = 'bla'; end

T = 10
N = 100

T.times do |i|
  Bla.create! :a => i, :b => "bla#{i}"
end

tm1 = Time.now

(0...T).map do |i|
  Thread.new do
    bla = Bla.find_by_a(i)
    bla.b = bla.b + "i"
    bla.save!
  end
end.each(&:join)

puts Time.now - tm1