add optional ruby-profiling with --profile-ruby

Gemfile

@@ -18,6 +18,8 @@ group(:maintenance) do
 end
 
 group(:development, :test) do
+  # for profiling
+  gem "ruby-prof"
 
   gem "simplecov"
   gem 'rack', "~> 1.5.1"

lib/chef/application/apply.rb

@@ -97,6 +97,12 @@ class Chef::Application::Apply < Chef::Application
     :description  => 'Enable whyrun mode',
     :boolean      => true
 
+  option :profile_ruby,
+    :long         => "--[no-]profile-ruby",
+    :description  => "Output ruby execution profile graph",
+    :boolean      => true,
+    :default      => false
+
   option :color,
     :long         => '--[no-]color',
     :boolean      => true,

lib/chef/application/client.rb

@@ -2,7 +2,7 @@
 # Author:: AJ Christensen (<aj@opscode.com)
 # Author:: Christopher Brown (<cb@opscode.com>)
 # Author:: Mark Mzyk (mmzyk@opscode.com)
-# Copyright:: Copyright (c) 2008 Opscode, Inc.
+# Copyright:: Copyright (c) 2008-2015 Chef Software, Inc.
 # License:: Apache License, Version 2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -55,6 +55,12 @@ class Chef::Application::Client < Chef::Application
     :boolean      => true,
     :default      => false
 
+  option :profile_ruby,
+    :long         => "--[no-]profile-ruby",
+    :description  => "Output ruby execution profile graph",
+    :boolean      => true,
+    :default      => false
+
   option :color,
     :long         => '--[no-]color',
     :boolean      => true,

lib/chef/application/solo.rb

@@ -1,7 +1,7 @@
 #
 # Author:: AJ Christensen (<aj@opscode.com>)
 # Author:: Mark Mzyk (mmzyk@opscode.com)
-# Copyright:: Copyright (c) 2008 Opscode, Inc.
+# Copyright:: Copyright (c) 2008-2015 Chef Software, Inc.
 # License:: Apache License, Version 2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -52,6 +52,12 @@ class Chef::Application::Solo < Chef::Application
     :boolean      => true,
     :default      => false
 
+  option :profile_ruby,
+    :long         => "--[no-]profile-ruby",
+    :description  => "Output ruby execution profile graph",
+    :boolean      => true,
+    :default      => false
+
   option :color,
     :long         => '--[no-]color',
     :boolean      => true,

lib/chef/client.rb

@@ -53,6 +53,11 @@
 require 'chef/mixin/deprecation'
 require 'ohai'
 require 'rbconfig'
+begin
+  require 'ruby-prof'
+rescue LoadError
+  # ruby-prof is optional.
+end
 
 class Chef
   # == Chef::Client
@@ -232,6 +237,8 @@ def initialize(json_attribs=nil, args={})
     # @return Always returns true.
     #
     def run
+      start_profiling
+
       run_error = nil
 
       runlock = RunLock.new(Chef::Config.lockfile)
@@ -284,6 +291,9 @@ def run
         run_completed_successfully
         events.run_completed(node)
 
+        # keep this inside the main loop to get exception backtraces
+        end_profiling
+
         # rebooting has to be the last thing we do, no exceptions.
         Chef::Platform::Rebooter.reboot_if_needed!(node)
       rescue Exception => run_error
@@ -891,6 +901,28 @@ def run_failed_notifications
     attr_reader :override_runlist
     attr_reader :specific_recipes
 
+    def profiling_prereqs!
+      if !defined? RubyProf
+        raise "You must have the ruby-prof gem installed in order to use --profile-ruby"
+      end
+    end
+
+    def start_profiling
+      return unless Chef::Config[:profile_ruby]
+      profiling_prereqs!
+      RubyProf.start
+    end
+
+    def end_profiling
+      return unless Chef::Config[:profile_ruby]
+      profiling_prereqs!
+      path = Chef::FileCache.create_cache_path("graph_profile.out", false)
+      File.open(path, "w+") do |file|
+        RubyProf::GraphPrinter.new(RubyProf.stop).print(file, {})
+      end
+      Chef::Log.warn("Ruby execution profile dumped to #{path}")
+    end
+
     def empty_directory?(path)
       !File.exists?(path) || (Dir.entries(path).size <= 2)
     end

spec/integration/client/client_spec.rb

@@ -301,6 +301,23 @@ class ::Blah
       result.error!
     end
 
+    it "should complete with success when using --profile-ruby and output a profile file" do
+      file 'config/client.rb', <<EOM
+local_mode true
+cookbook_path "#{path_to('cookbooks')}"
+EOM
+      result = shell_out!("#{chef_client} -c \"#{path_to('config/client.rb')}\" -o 'x::default' -z --profile-ruby", :cwd => chef_dir)
+      expect(File.exist?(path_to("config/local-mode-cache/cache/graph_profile.out"))).to be true
+    end
+
+    it "doesn't produce a profile when --profile-ruby is not present" do
+      file 'config/client.rb', <<EOM
+local_mode true
+cookbook_path "#{path_to('cookbooks')}"
+EOM
+      result = shell_out!("#{chef_client} -c \"#{path_to('config/client.rb')}\" -o 'x::default' -z", :cwd => chef_dir)
+      expect(File.exist?(path_to("config/local-mode-cache/cache/graph_profile.out"))).to be false
+    end
   end
 
   when_the_repository "has a cookbook that generates deprecation warnings" do