From ae934aef4af05f21d231015485cbc5a96df7a4d6 Mon Sep 17 00:00:00 2001 From: Jon Leighton Date: Fri, 12 Oct 2012 12:33:11 +0100 Subject: Don't allocate new strings in compiled attribute methods MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This improves memory and performance without having to use symbols which present DoS problems. Thanks @headius and @tenderlove for the suggestion. This was originally committed in f1765019ce9b6292f2264b4601dad5daaffe3a89, and then reverted in d3494903719682abc0948bef290af0d3d7b5a440 due to it causing problems in a real application. This second attempt should solve that. Benchmark --------- require 'active_record' require 'benchmark/ips' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') class Post < ActiveRecord::Base connection.create_table :posts, force: true do |t| t.string :name end end post = Post.create name: 'omg' Benchmark.ips do |r| r.report('Post.new') { Post.new name: 'omg' } r.report('post.name') { post.name } r.report('post.name=') { post.name = 'omg' } r.report('Post.find(1).name') { Post.find(1).name } end Before ------ Calculating ------------------------------------- Post.new 1419 i/100ms post.name 7538 i/100ms post.name= 3024 i/100ms Post.find(1).name 243 i/100ms ------------------------------------------------- Post.new 20637.6 (±12.7%) i/s - 102168 in 5.039578s post.name 1167897.7 (±18.2%) i/s - 5186144 in 4.983077s post.name= 64305.6 (±9.6%) i/s - 317520 in 4.998720s Post.find(1).name 2678.8 (±10.8%) i/s - 13365 in 5.051265s After ----- Calculating ------------------------------------- Post.new 1431 i/100ms post.name 7790 i/100ms post.name= 3181 i/100ms Post.find(1).name 245 i/100ms ------------------------------------------------- Post.new 21308.8 (±12.2%) i/s - 105894 in 5.053879s post.name 1534103.8 (±2.1%) i/s - 7634200 in 4.979405s post.name= 67441.0 (±7.5%) i/s - 337186 in 5.037871s Post.find(1).name 2681.9 (±10.6%) i/s - 13475 in 5.084511s --- activerecord/lib/active_record/core.rb | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'activerecord/lib/active_record/core.rb') diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb index 957027c1ee..94c6684700 100644 --- a/activerecord/lib/active_record/core.rb +++ b/activerecord/lib/active_record/core.rb @@ -83,7 +83,12 @@ module ActiveRecord @attribute_methods_mutex = Mutex.new # force attribute methods to be higher in inheritance hierarchy than other generated methods - generated_attribute_methods + generated_attribute_methods.const_set(:AttrNames, Module.new { + def self.const_missing(name) + const_set(name, [name.to_s.sub(/ATTR_/, '')].pack('h*').freeze) + end + }) + generated_feature_methods end -- cgit v1.2.3