Revert "Merge branch 'throttle-touching-of-objects' into 'master'"

app/models/concerns/throttled_touch.rb

-# ThrottledTouch can be used to throttle the number of updates triggered by
-# calling "touch" on an ActiveRecord model.
-module ThrottledTouch
-  # The amount of time to wait before "touch" can update a record again.
-  TOUCH_INTERVAL = 1.minute
-
-  def touch(*args)
-    super if (Time.zone.now - updated_at) > TOUCH_INTERVAL
-  end
-end

app/models/issue.rb

@@ -9,7 +9,6 @@ class Issue < ActiveRecord::Base
   include FasterCacheKeys
   include RelativePositioning
   include TimeTrackable
-  include ThrottledTouch
 
   DueDateStruct = Struct.new(:title, :name).freeze
   NoDueDate     = DueDateStruct.new('No Due Date', '0').freeze

app/models/merge_request.rb

@@ -7,7 +7,6 @@ class MergeRequest < ActiveRecord::Base
   include TimeTrackable
   include ManualInverseAssociation
   include EachBatch
-  include ThrottledTouch
 
   ignore_column :locked_at,
                 :ref_fetched

app/models/note.rb

@@ -15,7 +15,6 @@ class Note < ActiveRecord::Base
   include IgnorableColumn
   include Editable
   include Gitlab::SQL::Pattern
-  include ThrottledTouch
 
   module SpecialRole
     FIRST_TIME_CONTRIBUTOR = :first_time_contributor
@@ -56,7 +55,7 @@ class Note < ActiveRecord::Base
   participant :author
 
   belongs_to :project
-  belongs_to :noteable, polymorphic: true # rubocop:disable Cop/PolymorphicAssociations
+  belongs_to :noteable, polymorphic: true, touch: true # rubocop:disable Cop/PolymorphicAssociations
   belongs_to :author, class_name: "User"
   belongs_to :updated_by, class_name: "User"
   belongs_to :last_edited_by, class_name: 'User'
@@ -119,7 +118,6 @@ class Note < ActiveRecord::Base
   before_validation :set_discussion_id, on: :create
   after_save :keep_around_commit, if: :for_project_noteable?
   after_save :expire_etag_cache
-  after_save :touch_noteable
   after_destroy :expire_etag_cache
 
   class << self
@@ -371,38 +369,6 @@ class Note < ActiveRecord::Base
     Gitlab::EtagCaching::Store.new.touch(key)
   end
 
-  def touch(*args)
-    # We're not using an explicit transaction here because this would in all
-    # cases result in all future queries going to the primary, even if no writes
-    # are performed.
-    #
-    # We touch the noteable first so its SELECT query can run before our writes,
-    # ensuring it runs on a secondary (if no prior write took place).
-    touch_noteable
-    super
-  end
-
-  # By default Rails will issue an "SELECT *" for the relation, which is
-  # overkill for just updating the timestamps. To work around this we manually
-  # touch the data so we can SELECT only the columns we need.
-  def touch_noteable
-    # Commits are not stored in the DB so we can't touch them.
-    return if for_commit?
-
-    assoc = association(:noteable)
-
-    noteable_object =
-      if assoc.loaded?
-        noteable
-      else
-        # If the object is not loaded (e.g. when notes are loaded async) we
-        # _only_ want the data we actually need.
-        assoc.scope.select(:id, :updated_at).take
-      end
-
-    noteable_object&.touch
-  end
-
   def banzai_render_context(field)
     super.merge(noteable: noteable)
   end

changelogs/unreleased/throttle-touching-of-objects.yml

----
-title: Throttle the number of UPDATEs triggered by touch
-merge_request:
-author:
-type: performance

spec/models/concerns/issuable_spec.rb

@@ -171,7 +171,7 @@ describe Issuable do
 
     it "returns false when record has been updated" do
       allow(issue).to receive(:today?).and_return(true)
-      issue.update_attribute(:updated_at, 1.hour.ago)
+      issue.touch
       expect(issue.new?).to be_falsey
     end
   end

spec/models/issue_spec.rb

@@ -765,8 +765,4 @@ describe Issue do
       expect(described_class.public_only).to eq([public_issue])
     end
   end
-
-  it_behaves_like 'throttled touch' do
-    subject { create(:issue, updated_at: 1.hour.ago) }
-  end
 end

spec/models/merge_request_spec.rb

@@ -1851,8 +1851,4 @@ describe MergeRequest do
         .to change { project.open_merge_requests_count }.from(1).to(0)
     end
   end
-
-  it_behaves_like 'throttled touch' do
-    subject { create(:merge_request, updated_at: 1.hour.ago) }
-  end
 end

spec/models/note_spec.rb

@@ -5,7 +5,7 @@ describe Note do
 
   describe 'associations' do
     it { is_expected.to belong_to(:project) }
-    it { is_expected.to belong_to(:noteable).touch(false) }
+    it { is_expected.to belong_to(:noteable).touch(true) }
     it { is_expected.to belong_to(:author).class_name('User') }
 
     it { is_expected.to have_many(:todos).dependent(:destroy) }

spec/support/shared_examples/throttled_touch.rb

-shared_examples_for 'throttled touch' do
-  describe '#touch' do
-    it 'updates the updated_at timestamp' do
-      Timecop.freeze do
-        subject.touch
-        expect(subject.updated_at).to eq(Time.zone.now)
-      end
-    end
-
-    it 'updates the object at most once per minute' do
-      first_updated_at = Time.zone.now - (ThrottledTouch::TOUCH_INTERVAL * 2)
-      second_updated_at = Time.zone.now - (ThrottledTouch::TOUCH_INTERVAL * 1.5)
-
-      Timecop.freeze(first_updated_at) { subject.touch }
-      Timecop.freeze(second_updated_at) { subject.touch }
-
-      expect(subject.updated_at).to eq(first_updated_at)
-    end
-  end
-end