Remove cleanup_lfs_during_gc feature flag

This enables the feature, and also adds some documentation for it

app/workers/git_garbage_collect_worker.rb

@@ -91,7 +91,6 @@ class GitGarbageCollectWorker # rubocop:disable Scalability/IdempotentWorker
   end
 
   def cleanup_orphan_lfs_file_references(project)
-    return unless Feature.enabled?(:cleanup_lfs_during_gc, project)
     return if Gitlab::Database.read_only? # GitGarbageCollectWorker may be run on a Geo secondary
 
     ::Gitlab::Cleanup::OrphanLfsFileReferences.new(project, dry_run: false, logger: logger).run!

changelogs/unreleased/238605-remove-cleanup-lfs-during-gc-feature-flag.yml

+---
+title: Clean up unused LFS objects during repository housekeeping
+merge_request: 40979
+author:
+type: added

config/feature_flags/development/cleanup_lfs_during_gc.yml

----
-name: cleanup_lfs_during_gc
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/38813
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/238605
-group: group::source code
-type: development
-default_enabled: false

doc/administration/housekeeping.md

@@ -28,6 +28,9 @@ the `pushes_since_gc` value is 200 a `git gc` will be run.
   `git add`.
 - `git repack` ([man page](https://mirrors.edge.kernel.org/pub/software/scm/git/docs/git-repack.html)) re-organize existing packs into a single, more efficient pack.
 
+Housekeeping will also [remove unreferenced LFS files](../raketasks/cleanup.md#remove-unreferenced-lfs-files)
+from your project on the same schedule as the `git gc` operation, freeing up storage space for your project.
+
 You can find this option under your project's **Settings > General > Advanced**.
 
 ![Housekeeping settings](img/housekeeping_settings.png)

doc/user/project/repository/reducing_the_repo_size_using_git.md

@@ -230,6 +230,7 @@ This will:
 - Run `git gc` against the repository to remove unreferenced objects. Repacking your repository will temporarily
   cause the size of your repository to increase significantly, because the old pack files are not removed until the
   new pack files have been created.
+- Unlink any unused LFS objects currently attached to your project, freeing up storage space.
 - Recalculate the size of your repository on disk.
 
 You will receive an email notification with the recalculated repository size after the cleanup has completed.

spec/workers/git_garbage_collect_worker_spec.rb

@@ -129,57 +129,36 @@ RSpec.describe GitGarbageCollectWorker do
           let_it_be(:lfs_reference) { create(:lfs_objects_project, project: project) }
           let(:lfs_object) { lfs_reference.lfs_object }
 
-          context 'with cleanup_lfs_during_gc feature flag enabled' do
-            before do
-              stub_feature_flags(cleanup_lfs_during_gc: true)
+          it 'cleans up unreferenced LFS objects' do
+            expect_next_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences) do |svc|
+              expect(svc.project).to eq(project)
+              expect(svc.dry_run).to be_falsy
+              expect(svc).to receive(:run!).and_call_original
             end
 
-            it 'cleans up unreferenced LFS objects' do
-              expect_next_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences) do |svc|
-                expect(svc.project).to eq(project)
-                expect(svc.dry_run).to be_falsy
-                expect(svc).to receive(:run!).and_call_original
-              end
-
-              subject.perform(*params)
-
-              expect(project.lfs_objects.reload).not_to include(lfs_object)
-            end
-
-            it 'does nothing if the database is read-only' do
-              allow(Gitlab::Database).to receive(:read_only?) { true }
-
-              expect_any_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences).not_to receive(:run!)
-
-              subject.perform(*params)
+            subject.perform(*params)
 
-              expect(project.lfs_objects.reload).to include(lfs_object)
-            end
+            expect(project.lfs_objects.reload).not_to include(lfs_object)
+          end
 
-            it 'catches and logs exceptions' do
-              expect_any_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences)
-                .to receive(:run!)
-                .and_raise(/Failed/)
+          it 'catches and logs exceptions' do
+            expect_any_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences)
+              .to receive(:run!)
+              .and_raise(/Failed/)
 
-              expect(Gitlab::GitLogger).to receive(:warn)
-              expect(Gitlab::ErrorTracking).to receive(:track_and_raise_for_dev_exception)
+            expect(Gitlab::GitLogger).to receive(:warn)
+            expect(Gitlab::ErrorTracking).to receive(:track_and_raise_for_dev_exception)
 
-              subject.perform(*params)
-            end
+            subject.perform(*params)
           end
 
-          context 'with cleanup_lfs_during_gc feature flag disabled' do
-            before do
-              stub_feature_flags(cleanup_lfs_during_gc: false)
-            end
+          it 'does nothing if the database is read-only' do
+            allow(Gitlab::Database).to receive(:read_only?) { true }
+            expect_any_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences).not_to receive(:run!)
 
-            it 'does not clean up unreferenced LFS objects' do
-              expect_any_instance_of(Gitlab::Cleanup::OrphanLfsFileReferences).not_to receive(:run!)
-
-              subject.perform(*params)
+            subject.perform(*params)
 
-              expect(project.lfs_objects.reload).to include(lfs_object)
-            end
+            expect(project.lfs_objects.reload).to include(lfs_object)
           end
         end
       end