Remove ci_preload_runner_tags feature flag

Changelog: performance

app/models/ci/runner.rb

@@ -381,8 +381,6 @@ module Ci
     end
 
     def tag_list
-      return super unless Feature.enabled?(:ci_preload_runner_tags, default_enabled: :yaml)
-
       if tags.loaded?
         tags.map(&:name)
       else

app/services/ci/update_build_queue_service.rb

@@ -100,7 +100,7 @@ module Ci
 
     def tick_for(build, runners)
       runners = runners.with_recent_runner_queue
-      runners = runners.with_tags if Feature.enabled?(:ci_preload_runner_tags, default_enabled: :yaml)
+      runners = runners.with_tags
 
       metrics.observe_active_runners(-> { runners.to_a.size })
 

config/feature_flags/development/ci_preload_runner_tags.yml

----
-name: ci_preload_runner_tags
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/55543
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/323243
-milestone: '13.10'
-type: development
-group: group::memory
-default_enabled: true

spec/services/ci/update_build_queue_service_spec.rb

@@ -308,36 +308,12 @@ RSpec.describe Ci::UpdateBuildQueueService do
       let!(:build) { create(:ci_build, pipeline: pipeline, tag_list: %w[a b]) }
       let!(:project_runner) { create(:ci_runner, :project, :online, projects: [project], tag_list: %w[a b c]) }
 
-      context 'when ci_preload_runner_tags is enabled' do
-        before do
-          stub_feature_flags(
-            ci_preload_runner_tags: true
-          )
-        end
-
-        it 'does execute the same amount of queries regardless of number of runners' do
-          control_count = ActiveRecord::QueryRecorder.new { subject.tick(build) }.count
-
-          create_list(:ci_runner, 10, :project, :online, projects: [project], tag_list: %w[b c d])
-
-          expect { subject.tick(build) }.not_to exceed_all_query_limit(control_count)
-        end
-      end
-
-      context 'when ci_preload_runner_tags are disabled' do
-        before do
-          stub_feature_flags(
-            ci_preload_runner_tags: false
-          )
-        end
-
-        it 'does execute more queries for more runners' do
-          control_count = ActiveRecord::QueryRecorder.new { subject.tick(build) }.count
+      it 'does execute the same amount of queries regardless of number of runners' do
+        control_count = ActiveRecord::QueryRecorder.new { subject.tick(build) }.count
 
-          create_list(:ci_runner, 10, :project, :online, projects: [project], tag_list: %w[b c d])
+        create_list(:ci_runner, 10, :project, :online, projects: [project], tag_list: %w[b c d])
 
-          expect { subject.tick(build) }.to exceed_all_query_limit(control_count)
-        end
+        expect { subject.tick(build) }.not_to exceed_all_query_limit(control_count)
       end
     end
   end