Refactor LFS GC functions

- Remove options that currently aren't set
on `GarbageCollectLFSMetaObjectsOptions` and
`IterateLFSMetaObjectsForRepoOptions`.
- Simplify `IterateRepositoryIDsWithLFSMetaObjects` and
`IterateLFSMetaObjectsForRepo`.
- `IterateLFSMetaObjectsForRepo` was previously able to get in a
loop (`gc-lfs` doctor check was able to reproduce this) because the code
expected that the records would be updated to not match the SQL query,
but that wasn't the case. Simply enforce that only records higher than
the latest `id` from the previous iteration are allowed.
- For `gc-lfs` doctor check this was because `UpdatedLessRecentlyThan`
option was not set, which caused that records just marked as active in
the iteration weren't being filtered.
- Add unit tests
- Most likely a regression from 2cc3a6381c.
- The bug with `gc-lfs` was found on Codeberg.

(cherry picked from commit 7ffa7f5bcef12a0cc05aff660cb5217dc7e4c886)

models/git/TestIterateRepositoryIDsWithLFSMetaObjects/lfs_meta_object.yaml

@@ -0,0 +1,7 @@
+-
+
+  id: 1000
+  oid: 9d172e5c64b4f0024b9901ec6afe9ea052f3c9b6ff9f4b07956d8c48c86fca82
+  size: 25
+  repository_id: 1
+  created_unix: 1712309123

models/git/lfs.go

@@ -337,32 +337,29 @@ func GetRepoLFSSize(ctx context.Context, repoID int64) (int64, error) {
 func IterateRepositoryIDsWithLFSMetaObjects(ctx context.Context, f func(ctx context.Context, repoID, count int64) error) error {
 	batchSize := setting.Database.IterateBufferSize
 	sess := db.GetEngine(ctx)
-	id := int64(0)
+	var start int
 	type RepositoryCount struct {
 		RepositoryID int64
 		Count        int64
 	}
 	for {
 		counts := make([]*RepositoryCount, 0, batchSize)
-		sess.Select("repository_id, COUNT(id) AS count").
+		if err := sess.Select("repository_id, COUNT(id) AS count").
 			Table("lfs_meta_object").
-			Where("repository_id > ?", id).
 			GroupBy("repository_id").
-			OrderBy("repository_id ASC")
-
-		if err := sess.Limit(batchSize, 0).Find(&counts); err != nil {
+			OrderBy("repository_id ASC").Limit(batchSize, start).Find(&counts); err != nil {
 			return err
 		}
 		if len(counts) == 0 {
 			return nil
 		}
+		start += len(counts)
 
 		for _, count := range counts {
 			if err := f(ctx, count.RepositoryID, count.Count); err != nil {
 				return err
 			}
 		}
-		id = counts[len(counts)-1].RepositoryID
 	}
 }
 
@@ -370,25 +367,17 @@ func IterateRepositoryIDsWithLFSMetaObjects(ctx context.Context, f func(ctx cont
 type IterateLFSMetaObjectsForRepoOptions struct {
 	OlderThan               timeutil.TimeStamp
 	UpdatedLessRecentlyThan timeutil.TimeStamp
-	OrderByUpdated            bool
-	LoopFunctionAlwaysUpdates bool
 }
 
 // IterateLFSMetaObjectsForRepo provides a iterator for LFSMetaObjects per Repo
-func IterateLFSMetaObjectsForRepo(ctx context.Context, repoID int64, f func(context.Context, *LFSMetaObject, int64) error, opts *IterateLFSMetaObjectsForRepoOptions) error {
-	var start int
+func IterateLFSMetaObjectsForRepo(ctx context.Context, repoID int64, f func(context.Context, *LFSMetaObject) error, opts *IterateLFSMetaObjectsForRepoOptions) error {
 	batchSize := setting.Database.IterateBufferSize
 	engine := db.GetEngine(ctx)
-	type CountLFSMetaObject struct {
-		Count         int64
-		LFSMetaObject `xorm:"extends"`
-	}
-
 	id := int64(0)
 
 	for {
-		beans := make([]*CountLFSMetaObject, 0, batchSize)
-		sess := engine.Table("lfs_meta_object").Select("`lfs_meta_object`.*, COUNT(`l1`.oid) AS `count`").
+		beans := make([]*LFSMetaObject, 0, batchSize)
+		sess := engine.Table("lfs_meta_object").Select("`lfs_meta_object`.*").
 			Join("INNER", "`lfs_meta_object` AS l1", "`lfs_meta_object`.oid = `l1`.oid").
 			Where("`lfs_meta_object`.repository_id = ?", repoID)
 		if !opts.OlderThan.IsZero() {
@@ -397,25 +386,19 @@ func IterateLFSMetaObjectsForRepo(ctx context.Context, repoID int64, f func(cont
 		if !opts.UpdatedLessRecentlyThan.IsZero() {
 			sess.And("`lfs_meta_object`.updated_unix < ?", opts.UpdatedLessRecentlyThan)
 		}
-		sess.GroupBy("`lfs_meta_object`.id")
-		if opts.OrderByUpdated {
-			sess.OrderBy("`lfs_meta_object`.updated_unix ASC")
-		} else {
-			sess.And("`lfs_meta_object`.id > ?", id)
-			sess.OrderBy("`lfs_meta_object`.id ASC")
-		}
-		if err := sess.Limit(batchSize, start).Find(&beans); err != nil {
+		sess.GroupBy("`lfs_meta_object`.id").
+			And("`lfs_meta_object`.id > ?", id).
+			OrderBy("`lfs_meta_object`.id ASC")
+
+		if err := sess.Limit(batchSize, 0).Find(&beans); err != nil {
 			return err
 		}
 		if len(beans) == 0 {
 			return nil
 		}
-		if !opts.LoopFunctionAlwaysUpdates {
-			start += len(beans)
-		}
 
 		for _, bean := range beans {
-			if err := f(ctx, &bean.LFSMetaObject, bean.Count); err != nil {
+			if err := f(ctx, bean); err != nil {
 				return err
 			}
 		}

models/git/lfs_test.go

@@ -0,0 +1,101 @@
+// Copyright 2024 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package git
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/test"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIterateRepositoryIDsWithLFSMetaObjects(t *testing.T) {
+	defer unittest.OverrideFixtures(
+		unittest.FixturesOptions{
+			Dir:  filepath.Join(setting.AppWorkPath, "models/fixtures/"),
+			Base: setting.AppWorkPath,
+			Dirs: []string{"models/git/TestIterateRepositoryIDsWithLFSMetaObjects/"},
+		},
+	)()
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	type repocount struct {
+		repoid int64
+		count  int64
+	}
+	expected := []repocount{{1, 1}, {54, 4}}
+
+	t.Run("Normal batch size", func(t *testing.T) {
+		defer test.MockVariableValue(&setting.Database.IterateBufferSize, 20)()
+		cases := []repocount{}
+
+		err := IterateRepositoryIDsWithLFSMetaObjects(db.DefaultContext, func(ctx context.Context, repoID, count int64) error {
+			cases = append(cases, repocount{repoID, count})
+			return nil
+		})
+		assert.NoError(t, err)
+		assert.EqualValues(t, expected, cases)
+	})
+
+	t.Run("Low batch size", func(t *testing.T) {
+		defer test.MockVariableValue(&setting.Database.IterateBufferSize, 1)()
+		cases := []repocount{}
+
+		err := IterateRepositoryIDsWithLFSMetaObjects(db.DefaultContext, func(ctx context.Context, repoID, count int64) error {
+			cases = append(cases, repocount{repoID, count})
+			return nil
+		})
+		assert.NoError(t, err)
+		assert.EqualValues(t, expected, cases)
+	})
+}
+
+func TestIterateLFSMetaObjectsForRepo(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	expectedIDs := []int64{1, 2, 3, 4}
+
+	t.Run("Normal batch size", func(t *testing.T) {
+		defer test.MockVariableValue(&setting.Database.IterateBufferSize, 20)()
+		actualIDs := []int64{}
+
+		err := IterateLFSMetaObjectsForRepo(db.DefaultContext, 54, func(ctx context.Context, lo *LFSMetaObject) error {
+			actualIDs = append(actualIDs, lo.ID)
+			return nil
+		}, &IterateLFSMetaObjectsForRepoOptions{})
+		assert.NoError(t, err)
+		assert.EqualValues(t, expectedIDs, actualIDs)
+	})
+
+	t.Run("Low batch size", func(t *testing.T) {
+		defer test.MockVariableValue(&setting.Database.IterateBufferSize, 1)()
+		actualIDs := []int64{}
+
+		err := IterateLFSMetaObjectsForRepo(db.DefaultContext, 54, func(ctx context.Context, lo *LFSMetaObject) error {
+			actualIDs = append(actualIDs, lo.ID)
+			return nil
+		}, &IterateLFSMetaObjectsForRepoOptions{})
+		assert.NoError(t, err)
+		assert.EqualValues(t, expectedIDs, actualIDs)
+
+		t.Run("Batch handles updates", func(t *testing.T) {
+			actualIDs := []int64{}
+
+			err := IterateLFSMetaObjectsForRepo(db.DefaultContext, 54, func(ctx context.Context, lo *LFSMetaObject) error {
+				actualIDs = append(actualIDs, lo.ID)
+				_, err := db.DeleteByID[LFSMetaObject](ctx, lo.ID)
+				assert.NoError(t, err)
+				return nil
+			}, &IterateLFSMetaObjectsForRepoOptions{})
+			assert.NoError(t, err)
+			assert.EqualValues(t, expectedIDs, actualIDs)
+		})
+	})
+}

services/doctor/lfs.go

@@ -44,6 +44,7 @@ func garbageCollectLFSCheck(ctx context.Context, logger log.Logger, autofix bool
 		OlderThan: time.Now().Add(-24 * time.Hour * 7),
 		// We don't set the UpdatedLessRecentlyThan because we want to do a full GC
 	}); err != nil {
+		logger.Error("Couldn't garabage collect LFS objects: %v", err)
 		return err
 	}
 

services/repository/lfs.go

@@ -5,7 +5,6 @@ package repository
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"time"
 
@@ -25,8 +24,6 @@ type GarbageCollectLFSMetaObjectsOptions struct {
 	AutoFix                 bool
 	OlderThan               time.Time
 	UpdatedLessRecentlyThan time.Time
-	NumberToCheckPerRepo     int64
-	ProportionToCheckPerRepo float64
 }
 
 // GarbageCollectLFSMetaObjects garbage collects LFS objects for all repositories
@@ -49,9 +46,6 @@ func GarbageCollectLFSMetaObjects(ctx context.Context, opts GarbageCollectLFSMet
 			return err
 		}
 
-		if newMinimum := int64(float64(count) * opts.ProportionToCheckPerRepo); newMinimum > opts.NumberToCheckPerRepo && opts.NumberToCheckPerRepo != 0 {
-			opts.NumberToCheckPerRepo = newMinimum
-		}
 		return GarbageCollectLFSMetaObjectsForRepo(ctx, repo, opts)
 	})
 }
@@ -78,13 +72,9 @@ func GarbageCollectLFSMetaObjectsForRepo(ctx context.Context, repo *repo_model.R
 	defer gitRepo.Close()
 
 	store := lfs.NewContentStore()
-	errStop := errors.New("STOPERR")
 	objectFormat := git.ObjectFormatFromName(repo.ObjectFormatName)
 
-	err = git_model.IterateLFSMetaObjectsForRepo(ctx, repo.ID, func(ctx context.Context, metaObject *git_model.LFSMetaObject, count int64) error {
-		if opts.NumberToCheckPerRepo > 0 && total > opts.NumberToCheckPerRepo {
-			return errStop
-		}
+	err = git_model.IterateLFSMetaObjectsForRepo(ctx, repo.ID, func(ctx context.Context, metaObject *git_model.LFSMetaObject) error {
 		total++
 		pointerSha := git.ComputeBlobHash(objectFormat, []byte(metaObject.Pointer.StringContent()))
 
@@ -125,14 +115,8 @@ func GarbageCollectLFSMetaObjectsForRepo(ctx context.Context, repo *repo_model.R
 		// unassociated LFS object is genuinely unassociated.
 		OlderThan:               timeutil.TimeStamp(opts.OlderThan.Unix()),
 		UpdatedLessRecentlyThan: timeutil.TimeStamp(opts.UpdatedLessRecentlyThan.Unix()),
-		OrderByUpdated:            true,
-		LoopFunctionAlwaysUpdates: true,
 	})
-
-	if err == errStop {
-		opts.LogDetail("Processing stopped at %d total LFSMetaObjects in %-v", total, repo)
-		return nil
-	} else if err != nil {
+	if err != nil {
 		return err
 	}
 	return nil