diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index 0f89f2e88cc..4612abcbae8 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -55,7 +55,7 @@ class Projects::IssuesController < Projects::ApplicationController
   end
 
   def show
-    @participants = @issue.participants(current_user, @project)
+    @participants = @issue.participants(current_user)
     @note = @project.notes.new(noteable: @issue)
     @notes = @issue.notes.inc_author.fresh
     @noteable = @issue
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 7570934e727..98df6984bf7 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -246,7 +246,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   end
 
   def define_show_vars
-    @participants = @merge_request.participants(current_user, @project)
+    @participants = @merge_request.participants(current_user)
 
     # Build a note object for comment form
     @note = @project.notes.new(noteable: @merge_request)
diff --git a/app/models/concerns/mentionable.rb b/app/models/concerns/mentionable.rb
index 5b0ae411642..694403949c1 100644
--- a/app/models/concerns/mentionable.rb
+++ b/app/models/concerns/mentionable.rb
@@ -43,53 +43,53 @@ module Mentionable
 
   # Determine whether or not a cross-reference Note has already been created between this Mentionable and
   # the specified target.
-  def has_mentioned?(target)
+  def cross_reference_exists?(target)
     SystemNoteService.cross_reference_exists?(target, local_reference)
   end
 
-  def mentioned_users(current_user = nil)
-    return [] if mentionable_text.blank?
-
+  def all_references(current_user = self.author, text = self.mentionable_text)
     ext = Gitlab::ReferenceExtractor.new(self.project, current_user)
-    ext.analyze(mentionable_text)
-    ext.users.uniq
+    ext.analyze(text)
+    ext
+  end
+
+  def mentioned_users(current_user = nil)
+    all_references(current_user).users.uniq
   end
 
   # Extract GFM references to other Mentionables from this Mentionable. Always excludes its #local_reference.
-  def references(p = project, current_user = self.author, text = mentionable_text)
+  def referenced_mentionables(current_user = self.author, text = self.mentionable_text)
     return [] if text.blank?
 
-    ext = Gitlab::ReferenceExtractor.new(p, current_user)
-    ext.analyze(text)
-
-    (ext.issues + ext.merge_requests + ext.commits).uniq - [local_reference]
+    refs = all_references(current_user, text)
+    (refs.issues + refs.merge_requests + refs.commits).uniq - [local_reference]
   end
 
   # Create a cross-reference Note for each GFM reference to another Mentionable found in +mentionable_text+.
-  def create_cross_references!(p = project, a = author, without = [])
-    refs = references(p)
-
+  def create_cross_references!(author = self.author, without = [])
+    refs = referenced_mentionables(author)
+    
     # We're using this method instead of Array diffing because that requires
     # both of the object's `hash` values to be the same, which may not be the
     # case for otherwise identical Commit objects.
-    refs.reject! { |ref| without.include?(ref) }
+    refs.reject! { |ref| without.include?(ref) || cross_reference_exists?(ref) }
 
     refs.each do |ref|
-      SystemNoteService.cross_reference(ref, local_reference, a)
+      SystemNoteService.cross_reference(ref, local_reference, author)
     end
   end
 
   # When a mentionable field is changed, creates cross-reference notes that
   # don't already exist
-  def create_new_cross_references!(p = project, a = author)
+  def create_new_cross_references!(author = self.author)
     changes = detect_mentionable_changes
 
     return if changes.empty?
 
     original_text = changes.collect { |_, vals| vals.first }.join(' ')
 
-    preexisting = references(p, self.author, original_text)
-    create_cross_references!(p, a, preexisting)
+    preexisting = referenced_mentionables(author, original_text)
+    create_cross_references!(author, preexisting)
   end
 
   private
diff --git a/app/models/concerns/participable.rb b/app/models/concerns/participable.rb
index 7c9597333dd..d697c125c7d 100644
--- a/app/models/concerns/participable.rb
+++ b/app/models/concerns/participable.rb
@@ -37,7 +37,7 @@ module Participable
 
   # Be aware that this method makes a lot of sql queries.
   # Save result into variable if you are going to reuse it inside same request
-  def participants(current_user = self.author, project = self.project)
+  def participants(current_user = self.author)
     participants = self.class.participant_attrs.flat_map do |attr|
       meth = method(attr)
 
@@ -48,13 +48,11 @@ module Participable
           meth.call
         end
 
-      participants_for(value, current_user, project)
+      participants_for(value, current_user)
     end.compact.uniq
 
-    if project
-      participants.select! do |user|
-        user.can?(:read_project, project)
-      end
+    participants.select! do |user|
+      user.can?(:read_project, self.project)
     end
 
     participants
@@ -62,14 +60,14 @@ module Participable
 
   private
 
-  def participants_for(value, current_user = nil, project = nil)
+  def participants_for(value, current_user = nil)
     case value
     when User
       [value]
     when Enumerable, ActiveRecord::Relation
-      value.flat_map { |v| participants_for(v, current_user, project) }
+      value.flat_map { |v| participants_for(v, current_user) }
     when Participable
-      value.participants(current_user, project)
+      value.participants(current_user)
     end
   end
 end
diff --git a/app/models/note.rb b/app/models/note.rb
index de3b6df88f7..13eb28f5718 100644
--- a/app/models/note.rb
+++ b/app/models/note.rb
@@ -358,7 +358,7 @@ class Note < ActiveRecord::Base
   end
 
   def set_references
-    create_new_cross_references!(project, author)
+    create_new_cross_references!
   end
 
   def system?
diff --git a/app/services/git_push_service.rb b/app/services/git_push_service.rb
index f9a8265d2d4..81d47602f13 100644
--- a/app/services/git_push_service.rb
+++ b/app/services/git_push_service.rb
@@ -74,48 +74,30 @@ class GitPushService
   def process_commit_messages(ref)
     is_default_branch = is_default_branch?(ref)
 
+    authors = Hash.new do |hash, commit|
+      email = commit.author_email
+      return hash[email] if hash.has_key?(email)
+
+      hash[email] = commit_user(commit)
+    end
+
     @push_commits.each do |commit|
-      # Close issues if these commits were pushed to the project's default branch and the commit message matches the
-      # closing regex. Exclude any mentioned Issues from cross-referencing even if the commits are being pushed to
-      # a different branch.
-      issues_to_close = commit.closes_issues(user)
-
-      # Load commit author only if needed.
-      # For push with 1k commits it prevents 900+ requests in database
-      author = nil
-
       # Keep track of the issues that will be actually closed because they are on a default branch.
       # Hence, when creating cross-reference notes, the not-closed issues (on non-default branches)
       # will also have cross-reference.
-      actually_closed_issues = []
+      closed_issues = []
 
-      if issues_to_close.present? && is_default_branch
-        author ||= commit_user(commit)
-        actually_closed_issues = issues_to_close
-        issues_to_close.each do |issue|
-          Issues::CloseService.new(project, author, {}).execute(issue, commit)
+      if is_default_branch
+        # Close issues if these commits were pushed to the project's default branch and the commit message matches the
+        # closing regex. Exclude any mentioned Issues from cross-referencing even if the commits are being pushed to
+        # a different branch.
+        closed_issues = commit.closes_issues(user)
+        closed_issues.each do |issue|
+          Issues::CloseService.new(project, authors[commit], {}).execute(issue, commit)
         end
       end
 
-      if project.default_issues_tracker?
-        create_cross_reference_notes(commit, actually_closed_issues)
-      end
-    end
-  end
-
-  def create_cross_reference_notes(commit, issues_to_close)
-    # Create cross-reference notes for any other references than those given in issues_to_close.
-    # Omit any issues that were referenced in an issue-closing phrase, or have already been
-    # mentioned from this commit (probably from this commit being pushed to a different branch).
-    refs = commit.references(project, user) - issues_to_close
-    refs.reject! { |r| commit.has_mentioned?(r) }
-
-    if refs.present?
-      author ||= commit_user(commit)
-
-      refs.each do |r|
-        SystemNoteService.cross_reference(r, commit, author)
-      end
+      commit.create_cross_references!(authors[commit], closed_issues)
     end
   end
 
diff --git a/app/services/issues/create_service.rb b/app/services/issues/create_service.rb
index 1ea4b72216c..bcb380d3215 100644
--- a/app/services/issues/create_service.rb
+++ b/app/services/issues/create_service.rb
@@ -10,7 +10,7 @@ module Issues
         issue.update_attributes(label_ids: label_params)
         notification_service.new_issue(issue, current_user)
         event_service.open_issue(issue, current_user)
-        issue.create_cross_references!(issue.project, current_user)
+        issue.create_cross_references!(current_user)
         execute_hooks(issue, 'open')
       end
 
diff --git a/app/services/issues/update_service.rb b/app/services/issues/update_service.rb
index 2fc6ef7f356..2b5426ad452 100644
--- a/app/services/issues/update_service.rb
+++ b/app/services/issues/update_service.rb
@@ -35,7 +35,7 @@ module Issues
           create_title_change_note(issue, issue.previous_changes['title'].first)
         end
 
-        issue.create_new_cross_references!(issue.project, current_user)
+        issue.create_new_cross_references!
         execute_hooks(issue, 'update')
       end
 
diff --git a/app/services/merge_requests/create_service.rb b/app/services/merge_requests/create_service.rb
index 9651b16462c..009d5a6867e 100644
--- a/app/services/merge_requests/create_service.rb
+++ b/app/services/merge_requests/create_service.rb
@@ -18,7 +18,7 @@ module MergeRequests
         merge_request.update_attributes(label_ids: label_params)
         event_service.open_mr(merge_request, current_user)
         notification_service.new_merge_request(merge_request, current_user)
-        merge_request.create_cross_references!(merge_request.project, current_user)
+        merge_request.create_cross_references!(current_user)
         execute_hooks(merge_request)
       end
 
diff --git a/app/services/merge_requests/update_service.rb b/app/services/merge_requests/update_service.rb
index 25d79e22e39..ebbe0af803b 100644
--- a/app/services/merge_requests/update_service.rb
+++ b/app/services/merge_requests/update_service.rb
@@ -59,7 +59,7 @@ module MergeRequests
           merge_request.mark_as_unchecked
         end
 
-        merge_request.create_new_cross_references!(merge_request.project, current_user)
+        merge_request.create_new_cross_references!
         execute_hooks(merge_request, 'update')
       end
 
diff --git a/lib/gitlab/reference_extractor.rb b/lib/gitlab/reference_extractor.rb
index 0961bd80421..30497e274c2 100644
--- a/lib/gitlab/reference_extractor.rb
+++ b/lib/gitlab/reference_extractor.rb
@@ -39,6 +39,8 @@ module Gitlab
     #
     # Returns the results Array for the requested filter type
     def pipeline_result(filter_type)
+      return [] if @text.blank?
+      
       klass  = filter_type.to_s.camelize + 'ReferenceFilter'
       filter = Gitlab::Markdown.const_get(klass)
 
diff --git a/spec/models/concerns/mentionable_spec.rb b/spec/models/concerns/mentionable_spec.rb
index 2d6fe003215..6179882e935 100644
--- a/spec/models/concerns/mentionable_spec.rb
+++ b/spec/models/concerns/mentionable_spec.rb
@@ -25,7 +25,7 @@ describe Issue, "Mentionable" do
     it 'correctly removes already-mentioned Commits' do
       expect(SystemNoteService).not_to receive(:cross_reference)
 
-      issue.create_cross_references!(project, author, [commit2])
+      issue.create_cross_references!(author, [commit2])
     end
   end
 
diff --git a/spec/services/git_push_service_spec.rb b/spec/services/git_push_service_spec.rb
index c483060fd73..bb620783410 100644
--- a/spec/services/git_push_service_spec.rb
+++ b/spec/services/git_push_service_spec.rb
@@ -155,7 +155,7 @@ describe GitPushService do
 
     before do
       allow(commit).to receive_messages(
-        safe_message: "this commit \n mentions ##{issue.id}",
+        safe_message: "this commit \n mentions ##{issue.iid}",
         references: [issue],
         author_name: commit_author.name,
         author_email: commit_author.email
diff --git a/spec/support/mentionable_shared_examples.rb b/spec/support/mentionable_shared_examples.rb
index e3de0afb448..220566a22b6 100644
--- a/spec/support/mentionable_shared_examples.rb
+++ b/spec/support/mentionable_shared_examples.rb
@@ -65,7 +65,7 @@ shared_examples 'a mentionable' do
 
   it "extracts references from its reference property" do
     # De-duplicate and omit itself
-    refs = subject.references(project)
+    refs = subject.referenced_mentionables
     expect(refs.size).to eq(6)
     expect(refs).to include(mentioned_issue)
     expect(refs).to include(mentioned_mr)
@@ -84,14 +84,14 @@ shared_examples 'a mentionable' do
         with(referenced, subject.local_reference, author)
     end
 
-    subject.create_cross_references!(project, author)
+    subject.create_cross_references!
   end
 
   it 'detects existing cross-references' do
     SystemNoteService.cross_reference(mentioned_issue, subject.local_reference, author)
 
-    expect(subject).to have_mentioned(mentioned_issue)
-    expect(subject).not_to have_mentioned(mentioned_mr)
+    expect(subject.cross_reference_exists?(mentioned_issue)).to be_truthy
+    expect(subject.cross_reference_exists?(mentioned_mr)).to be_falsey
   end
 end
 
@@ -143,6 +143,6 @@ shared_examples 'an editable mentionable' do
     end
 
     set_mentionable_text.call(new_text)
-    subject.create_new_cross_references!(project, author)
+    subject.create_new_cross_references!(author)
   end
 end