From a19e91f0fab13cca61acdb1f33e27be2323b9786 Mon Sep 17 00:00:00 2001 From: Ryuta Kamizono Date: Mon, 22 Jan 2018 10:46:36 +0900 Subject: PERF: Recover `changes_applied` performance (#31698) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit #30985 caused `object.save` performance regression since calling `changes` in `changes_applied` is very slow. We don't need to call the expensive method in `changes_applied` as long as `@attributes` is tracked by mutation tracker. https://gist.github.com/kamipo/1a9f4f3891803b914fc72ede98268aa2 Before: ``` Warming up -------------------------------------- create_string_columns 73.000 i/100ms Calculating ------------------------------------- create_string_columns 722.256 (± 5.8%) i/s - 3.650k in 5.073031s ``` After: ``` Warming up -------------------------------------- create_string_columns 96.000 i/100ms Calculating ------------------------------------- create_string_columns 950.224 (± 7.7%) i/s - 4.800k in 5.084837s ``` --- activerecord/lib/active_record/attribute_methods/dirty.rb | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'activerecord/lib/active_record/attribute_methods') diff --git a/activerecord/lib/active_record/attribute_methods/dirty.rb b/activerecord/lib/active_record/attribute_methods/dirty.rb index 3de6fe566d..df4c79b0f6 100644 --- a/activerecord/lib/active_record/attribute_methods/dirty.rb +++ b/activerecord/lib/active_record/attribute_methods/dirty.rb @@ -32,9 +32,7 @@ module ActiveRecord # reload the record and clears changed attributes. def reload(*) super.tap do - @previously_changed = ActiveSupport::HashWithIndifferentAccess.new @mutations_before_last_save = nil - @attributes_changed_by_setter = ActiveSupport::HashWithIndifferentAccess.new @mutations_from_database = nil end end @@ -114,12 +112,12 @@ module ActiveRecord # Alias for +changed+ def changed_attribute_names_to_save - changes_to_save.keys + mutations_from_database.changed_attribute_names end # Alias for +changed_attributes+ def attributes_in_database - changes_to_save.transform_values(&:first) + mutations_from_database.changed_values end private -- cgit v1.2.3