Graceful: Xorm, RepoIndexer, Cron and Others (#9282)

* Change graceful to use a singleton obtained through GetManager instead of a global.
* Graceful: Make TestPullRequests shutdownable
* Graceful: Make the cron tasks graceful
* Graceful: AddTestPullRequest run in graceful ctx
* Graceful: SyncMirrors shutdown
* Graceful: SetDefaultContext for Xorm to be HammerContext
* Avoid starting graceful for migrate commands and checkout
* Graceful: DeliverHooks now can be shutdown
* Fix multiple syncing errors in modules/sync/UniqueQueue &  Make UniqueQueue closable
* Begin the process of making the repo indexer shutdown gracefully

37 files changed, 631 insertions, 290 deletions

diff --git a/cmd/migrate.go b/cmd/migrate.go
index 1fa1d09e25..2428925887 100644
--- a/cmd/migrate.go
+++ b/cmd/migrate.go
@@ -5,6 +5,8 @@
 package cmd
 
 import (
+	"context"
+
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/models/migrations"
 	"code.gitea.io/gitea/modules/log"
@@ -32,7 +34,7 @@ func runMigrate(ctx *cli.Context) error {
 	log.Trace("Log path: %s", setting.LogRootPath)
 	setting.InitDBConfig()
 
-	if err := models.NewEngine(migrations.Migrate); err != nil {
+	if err := models.NewEngine(context.Background(), migrations.Migrate); err != nil {
 		log.Fatal("Failed to initialize ORM engine: %v", err)
 		return err
 	}
diff --git a/cmd/web.go b/cmd/web.go
index cc00a32198..243b9a4108 100644
--- a/cmd/web.go
+++ b/cmd/web.go
@@ -5,6 +5,7 @@
 package cmd
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	_ "net/http/pprof" // Used for debugging if enabled and a web server is running
@@ -96,6 +97,10 @@ func runLetsEncryptFallbackHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 func runWeb(ctx *cli.Context) error {
+	managerCtx, cancel := context.WithCancel(context.Background())
+	graceful.InitManager(managerCtx)
+	defer cancel()
+
 	if os.Getppid() > 1 && len(os.Getenv("LISTEN_FDS")) > 0 {
 		log.Info("Restarting Gitea on PID: %d from parent PID: %d", os.Getpid(), os.Getppid())
 	} else {
@@ -108,7 +113,7 @@ func runWeb(ctx *cli.Context) error {
 	}
 
 	// Perform global initialization
-	routers.GlobalInit()
+	routers.GlobalInit(graceful.GetManager().HammerContext())
 
 	// Set up Macaron
 	m := routes.NewMacaron()
@@ -199,8 +204,7 @@ func runWeb(ctx *cli.Context) error {
 		log.Critical("Failed to start server: %v", err)
 	}
 	log.Info("HTTP Listener: %s Closed", listenAddr)
-	graceful.Manager.WaitForServers()
-	graceful.Manager.WaitForTerminate()
+	<-graceful.GetManager().Done()
 	log.Info("PID: %d Gitea Web Finished", os.Getpid())
 	log.Close()
 	return nil
diff --git a/cmd/web_graceful.go b/cmd/web_graceful.go
index 5f8b85b390..f3c41766af 100644
--- a/cmd/web_graceful.go
+++ b/cmd/web_graceful.go
@@ -28,13 +28,13 @@ func runHTTPSWithTLSConfig(network, listenAddr string, tlsConfig *tls.Config, m
 
 // NoHTTPRedirector tells our cleanup routine that we will not be using a fallback http redirector
 func NoHTTPRedirector() {
-	graceful.Manager.InformCleanup()
+	graceful.GetManager().InformCleanup()
 }
 
 // NoMainListener tells our cleanup routine that we will not be using a possibly provided listener
 // for our main HTTP/HTTPS service
 func NoMainListener() {
-	graceful.Manager.InformCleanup()
+	graceful.GetManager().InformCleanup()
 }
 
 func runFCGI(network, listenAddr string, m http.Handler) error {
diff --git a/contrib/pr/checkout.go b/contrib/pr/checkout.go
index 9c06357295..34cd82ff0a 100644
--- a/contrib/pr/checkout.go
+++ b/contrib/pr/checkout.go
@@ -5,6 +5,7 @@ Checkout a PR and load the tests data into sqlite database
 */
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -92,7 +93,7 @@ func runPR() {
 	//x, err = xorm.NewEngine("sqlite3", "file::memory:?cache=shared")
 
 	var helper testfixtures.Helper = &testfixtures.SQLite{}
-	models.NewEngine(func(_ *xorm.Engine) error {
+	models.NewEngine(context.Background(), func(_ *xorm.Engine) error {
 		return nil
 	})
 	models.HasEngine = true
diff --git a/integrations/auth_ldap_test.go b/integrations/auth_ldap_test.go
index 5cb2bad57d..80286c09e6 100644
--- a/integrations/auth_ldap_test.go
+++ b/integrations/auth_ldap_test.go
@@ -5,6 +5,7 @@
 package integrations
 
 import (
+	"context"
 	"net/http"
 	"os"
 	"strings"
@@ -147,7 +148,7 @@ func TestLDAPUserSync(t *testing.T) {
 	}
 	defer prepareTestEnv(t)()
 	addAuthSourceLDAP(t, "")
-	models.SyncExternalUsers()
+	models.SyncExternalUsers(context.Background())
 
 	session := loginUser(t, "user1")
 	// Check if users exists
@@ -206,7 +207,8 @@ func TestLDAPUserSSHKeySync(t *testing.T) {
 	}
 	defer prepareTestEnv(t)()
 	addAuthSourceLDAP(t, "sshPublicKey")
-	models.SyncExternalUsers()
+
+	models.SyncExternalUsers(context.Background())
 
 	// Check if users has SSH keys synced
 	for _, u := range gitLDAPUsers {
diff --git a/integrations/integration_test.go b/integrations/integration_test.go
index 5da9e04c78..bf363f3b4d 100644
--- a/integrations/integration_test.go
+++ b/integrations/integration_test.go
@@ -6,6 +6,7 @@ package integrations
 
 import (
 	"bytes"
+	"context"
 	"database/sql"
 	"encoding/json"
 	"fmt"
@@ -24,6 +25,7 @@ import (
 
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/routers"
 	"code.gitea.io/gitea/routers/routes"
@@ -55,6 +57,10 @@ func NewNilResponseRecorder() *NilResponseRecorder {
 }
 
 func TestMain(m *testing.M) {
+	managerCtx, cancel := context.WithCancel(context.Background())
+	graceful.InitManager(managerCtx)
+	defer cancel()
+
 	initIntegrationTest()
 	mac = routes.NewMacaron()
 	routes.RegisterRoutes(mac)
@@ -171,7 +177,7 @@ func initIntegrationTest() {
 		}
 		defer db.Close()
 	}
-	routers.GlobalInit()
+	routers.GlobalInit(graceful.GetManager().HammerContext())
 }
 
 func prepareTestEnv(t testing.TB, skip ...int) func() {
diff --git a/integrations/migration-test/migration_test.go b/integrations/migration-test/migration_test.go
index 4fe36dc021..c274d482da 100644
--- a/integrations/migration-test/migration_test.go
+++ b/integrations/migration-test/migration_test.go
@@ -6,6 +6,7 @@ package migrations
 
 import (
 	"compress/gzip"
+	"context"
 	"database/sql"
 	"fmt"
 	"io/ioutil"
@@ -220,7 +221,7 @@ func doMigrationTest(t *testing.T, version string) {
 	err := models.SetEngine()
 	assert.NoError(t, err)
 
-	err = models.NewEngine(wrappedMigrate)
+	err = models.NewEngine(context.Background(), wrappedMigrate)
 	assert.NoError(t, err)
 	currentEngine.Close()
 }
diff --git a/models/branches.go b/models/branches.go
index bb99cffa05..045019314a 100644
--- a/models/branches.go
+++ b/models/branches.go
@@ -5,6 +5,7 @@
 package models
 
 import (
+	"context"
 	"fmt"
 	"time"
 
@@ -525,7 +526,8 @@ func (deletedBranch *DeletedBranch) LoadUser() {
 }
 
 // RemoveOldDeletedBranches removes old deleted branches
-func RemoveOldDeletedBranches() {
+func RemoveOldDeletedBranches(ctx context.Context) {
+	// Nothing to do for shutdown or terminate
 	log.Trace("Doing: DeletedBranchesCleanup")
 
 	deleteBefore := time.Now().Add(-setting.Cron.DeletedBranchesCleanup.OlderThan)
diff --git a/models/models.go b/models/models.go
index 8c10e7abfc..9eb174e200 100644
--- a/models/models.go
+++ b/models/models.go
@@ -6,6 +6,7 @@
 package models
 
 import (
+	"context"
 	"database/sql"
 	"errors"
 	"fmt"
@@ -164,11 +165,13 @@ func SetEngine() (err error) {
 }
 
 // NewEngine initializes a new xorm.Engine
-func NewEngine(migrateFunc func(*xorm.Engine) error) (err error) {
+func NewEngine(ctx context.Context, migrateFunc func(*xorm.Engine) error) (err error) {
 	if err = SetEngine(); err != nil {
 		return err
 	}
 
+	x.SetDefaultContext(ctx)
+
 	if err = x.Ping(); err != nil {
 		return err
 	}
diff --git a/models/pull_list.go b/models/pull_list.go
index 49d04ba0b8..1376978353 100644
--- a/models/pull_list.go
+++ b/models/pull_list.go
@@ -68,11 +68,12 @@ func GetUnmergedPullRequestsByBaseInfo(repoID int64, branch string) ([]*PullRequ
 		Find(&prs)
 }
 
-// GetPullRequestsByCheckStatus returns all pull requests according the special checking status.
-func GetPullRequestsByCheckStatus(status PullRequestStatus) ([]*PullRequest, error) {
-	prs := make([]*PullRequest, 0, 10)
-	return prs, x.
+// GetPullRequestIDsByCheckStatus returns all pull requests according the special checking status.
+func GetPullRequestIDsByCheckStatus(status PullRequestStatus) ([]int64, error) {
+	prs := make([]int64, 0, 10)
+	return prs, x.Table("pull_request").
 		Where("status=?", status).
+		Cols("pull_request.id").
 		Find(&prs)
 }
 
diff --git a/models/repo.go b/models/repo.go
index f4ac75b8f0..c7eee3c1ec 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -7,6 +7,7 @@ package models
 
 import (
 	"bytes"
+	"context"
 	"crypto/md5"
 	"errors"
 	"fmt"
@@ -2098,19 +2099,27 @@ func DeleteRepositoryArchives() error {
 }
 
 // DeleteOldRepositoryArchives deletes old repository archives.
-func DeleteOldRepositoryArchives() {
+func DeleteOldRepositoryArchives(ctx context.Context) {
 	log.Trace("Doing: ArchiveCleanup")
 
-	if err := x.Where("id > 0").Iterate(new(Repository), deleteOldRepositoryArchives); err != nil {
+	if err := x.Where("id > 0").Iterate(new(Repository), func(idx int, bean interface{}) error {
+		return deleteOldRepositoryArchives(ctx, idx, bean)
+	}); err != nil {
 		log.Error("ArchiveClean: %v", err)
 	}
 }
 
-func deleteOldRepositoryArchives(idx int, bean interface{}) error {
+func deleteOldRepositoryArchives(ctx context.Context, idx int, bean interface{}) error {
 	repo := bean.(*Repository)
 	basePath := filepath.Join(repo.RepoPath(), "archives")
 
 	for _, ty := range []string{"zip", "targz"} {
+		select {
+		case <-ctx.Done():
+			return fmt.Errorf("Aborted due to shutdown:\nin delete of old repository archives %v\nat delete file %s", repo, ty)
+		default:
+		}
+
 		path := filepath.Join(basePath, ty)
 		file, err := os.Open(path)
 		if err != nil {
@@ -2133,6 +2142,11 @@ func deleteOldRepositoryArchives(idx int, bean interface{}) error {
 		minimumOldestTime := time.Now().Add(-setting.Cron.ArchiveCleanup.OlderThan)
 		for _, info := range files {
 			if info.ModTime().Before(minimumOldestTime) && !info.IsDir() {
+				select {
+				case <-ctx.Done():
+					return fmt.Errorf("Aborted due to shutdown:\nin delete of old repository archives %v\nat delete file %s - %s", repo, ty, info.Name())
+				default:
+				}
 				toDelete := filepath.Join(path, info.Name())
 				// This is a best-effort purge, so we do not check error codes to confirm removal.
 				if err = os.Remove(toDelete); err != nil {
@@ -2226,13 +2240,17 @@ func SyncRepositoryHooks() error {
 }
 
 // GitFsck calls 'git fsck' to check repository health.
-func GitFsck() {
+func GitFsck(ctx context.Context) {
 	log.Trace("Doing: GitFsck")
-
 	if err := x.
 		Where("id>0 AND is_fsck_enabled=?", true).BufferSize(setting.Database.IterateBufferSize).
 		Iterate(new(Repository),
 			func(idx int, bean interface{}) error {
+				select {
+				case <-ctx.Done():
+					return fmt.Errorf("Aborted due to shutdown")
+				default:
+				}
 				repo := bean.(*Repository)
 				repoPath := repo.RepoPath()
 				log.Trace("Running health check on repository %s", repoPath)
@@ -2278,13 +2296,19 @@ type repoChecker struct {
 	desc                 string
 }
 
-func repoStatsCheck(checker *repoChecker) {
+func repoStatsCheck(ctx context.Context, checker *repoChecker) {
 	results, err := x.Query(checker.querySQL)
 	if err != nil {
 		log.Error("Select %s: %v", checker.desc, err)
 		return
 	}
 	for _, result := range results {
+		select {
+		case <-ctx.Done():
+			log.Warn("CheckRepoStats: Aborting due to shutdown")
+			return
+		default:
+		}
 		id := com.StrTo(result["id"]).MustInt64()
 		log.Trace("Updating %s: %d", checker.desc, id)
 		_, err = x.Exec(checker.correctSQL, id, id)
@@ -2295,7 +2319,7 @@ func repoStatsCheck(checker *repoChecker) {
 }
 
 // CheckRepoStats checks the repository stats
-func CheckRepoStats() {
+func CheckRepoStats(ctx context.Context) {
 	log.Trace("Doing: CheckRepoStats")
 
 	checkers := []*repoChecker{
@@ -2331,7 +2355,13 @@ func CheckRepoStats() {
 		},
 	}
 	for i := range checkers {
-		repoStatsCheck(checkers[i])
+		select {
+		case <-ctx.Done():
+			log.Warn("CheckRepoStats: Aborting due to shutdown")
+			return
+		default:
+			repoStatsCheck(ctx, checkers[i])
+		}
 	}
 
 	// ***** START: Repository.NumClosedIssues *****
@@ -2341,6 +2371,12 @@ func CheckRepoStats() {
 		log.Error("Select %s: %v", desc, err)
 	} else {
 		for _, result := range results {
+			select {
+			case <-ctx.Done():
+				log.Warn("CheckRepoStats: Aborting due to shutdown")
+				return
+			default:
+			}
 			id := com.StrTo(result["id"]).MustInt64()
 			log.Trace("Updating %s: %d", desc, id)
 			_, err = x.Exec("UPDATE `repository` SET num_closed_issues=(SELECT COUNT(*) FROM `issue` WHERE repo_id=? AND is_closed=? AND is_pull=?) WHERE id=?", id, true, false, id)
@@ -2358,6 +2394,12 @@ func CheckRepoStats() {
 		log.Error("Select %s: %v", desc, err)
 	} else {
 		for _, result := range results {
+			select {
+			case <-ctx.Done():
+				log.Warn("CheckRepoStats: Aborting due to shutdown")
+				return
+			default:
+			}
 			id := com.StrTo(result["id"]).MustInt64()
 			log.Trace("Updating %s: %d", desc, id)
 			_, err = x.Exec("UPDATE `repository` SET num_closed_pulls=(SELECT COUNT(*) FROM `issue` WHERE repo_id=? AND is_closed=? AND is_pull=?) WHERE id=?", id, true, true, id)
@@ -2375,6 +2417,12 @@ func CheckRepoStats() {
 		log.Error("Select repository count 'num_forks': %v", err)
 	} else {
 		for _, result := range results {
+			select {
+			case <-ctx.Done():
+				log.Warn("CheckRepoStats: Aborting due to shutdown")
+				return
+			default:
+			}
 			id := com.StrTo(result["id"]).MustInt64()
 			log.Trace("Updating repository count 'num_forks': %d", id)
 
diff --git a/models/repo_indexer.go b/models/repo_indexer.go
index 138ef54d33..aee3c74b35 100644
--- a/models/repo_indexer.go
+++ b/models/repo_indexer.go
@@ -4,6 +4,12 @@
 
 package models
 
+import (
+	"fmt"
+
+	"xorm.io/builder"
+)
+
 // RepoIndexerStatus status of a repo's entry in the repo indexer
 // For now, implicitly refers to default branch
 type RepoIndexerStatus struct {
@@ -12,6 +18,31 @@ type RepoIndexerStatus struct {
 	CommitSha string `xorm:"VARCHAR(40)"`
 }
 
+// GetUnindexedRepos returns repos which do not have an indexer status
+func GetUnindexedRepos(maxRepoID int64, page, pageSize int) ([]int64, error) {
+	ids := make([]int64, 0, 50)
+	cond := builder.Cond(builder.IsNull{
+		"repo_indexer_status.id",
+	})
+	sess := x.Table("repository").Join("LEFT OUTER", "repo_indexer_status", "repository.id = repo_indexer_status.repo_id")
+	if maxRepoID > 0 {
+		cond = builder.And(cond, builder.Lte{
+			"repository.id": maxRepoID,
+		})
+	}
+	if page >= 0 && pageSize > 0 {
+		start := 0
+		if page > 0 {
+			start = (page - 1) * pageSize
+		}
+		sess.Limit(pageSize, start)
+	}
+
+	sess.Where(cond).Cols("repository.id").Desc("repository.id")
+	err := sess.Find(&ids)
+	return ids, err
+}
+
 // GetIndexerStatus loads repo codes indxer status
 func (repo *Repository) GetIndexerStatus() error {
 	if repo.IndexerStatus != nil {
@@ -31,15 +62,21 @@ func (repo *Repository) GetIndexerStatus() error {
 // UpdateIndexerStatus updates indexer status
 func (repo *Repository) UpdateIndexerStatus(sha string) error {
 	if err := repo.GetIndexerStatus(); err != nil {
-		return err
+		return fmt.Errorf("UpdateIndexerStatus: Unable to getIndexerStatus for repo: %s/%s Error: %v", repo.MustOwnerName(), repo.Name, err)
 	}
 	if len(repo.IndexerStatus.CommitSha) == 0 {
 		repo.IndexerStatus.CommitSha = sha
 		_, err := x.Insert(repo.IndexerStatus)
-		return err
+		if err != nil {
+			return fmt.Errorf("UpdateIndexerStatus: Unable to insert repoIndexerStatus for repo: %s/%s Sha: %s Error: %v", repo.MustOwnerName(), repo.Name, sha, err)
+		}
+		return nil
 	}
 	repo.IndexerStatus.CommitSha = sha
 	_, err := x.ID(repo.IndexerStatus.ID).Cols("commit_sha").
 		Update(repo.IndexerStatus)
-	return err
+	if err != nil {
+		return fmt.Errorf("UpdateIndexerStatus: Unable to update repoIndexerStatus for repo: %s/%s Sha: %s Error: %v", repo.MustOwnerName(), repo.Name, sha, err)
+	}
+	return nil
 }
diff --git a/models/user.go b/models/user.go
index 2cef2e5dec..0454158de6 100644
--- a/models/user.go
+++ b/models/user.go
@@ -7,6 +7,7 @@ package models
 
 import (
 	"container/list"
+	"context"
 	"crypto/md5"
 	"crypto/sha256"
 	"crypto/subtle"
@@ -1695,7 +1696,7 @@ func synchronizeLdapSSHPublicKeys(usr *User, s *LoginSource, sshPublicKeys []str
 }
 
 // SyncExternalUsers is used to synchronize users with external authorization source
-func SyncExternalUsers() {
+func SyncExternalUsers(ctx context.Context) {
 	log.Trace("Doing: SyncExternalUsers")
 
 	ls, err := LoginSources()
@@ -1710,6 +1711,12 @@ func SyncExternalUsers() {
 		if !s.IsActived || !s.IsSyncEnabled {
 			continue
 		}
+		select {
+		case <-ctx.Done():
+			log.Warn("SyncExternalUsers: Aborted due to shutdown before update of %s", s.Name)
+			return
+		default:
+		}
 
 		if s.IsLDAP() {
 			log.Trace("Doing: SyncExternalUsers[%s]", s.Name)
@@ -1727,6 +1734,12 @@ func SyncExternalUsers() {
 				log.Error("SyncExternalUsers: %v", err)
 				return
 			}
+			select {
+			case <-ctx.Done():
+				log.Warn("SyncExternalUsers: Aborted due to shutdown before update of %s", s.Name)
+				return
+			default:
+			}
 
 			sr, err := s.LDAP().SearchEntries()
 			if err != nil {
@@ -1735,6 +1748,19 @@ func SyncExternalUsers() {
 			}
 
 			for _, su := range sr {
+				select {
+				case <-ctx.Done():
+					log.Warn("SyncExternalUsers: Aborted due to shutdown at update of %s before completed update of users", s.Name)
+					// Rewrite authorized_keys file if LDAP Public SSH Key attribute is set and any key was added or removed
+					if sshKeysNeedUpdate {
+						err = RewriteAllPublicKeys()
+						if err != nil {
+							log.Error("RewriteAllPublicKeys: %v", err)
+						}
+					}
+					return
+				default:
+				}
 				if len(su.Username) == 0 {
 					continue
 				}
@@ -1819,6 +1845,13 @@ func SyncExternalUsers() {
 				}
 			}
 
+			select {
+			case <-ctx.Done():
+				log.Warn("SyncExternalUsers: Aborted due to shutdown at update of %s before delete users", s.Name)
+				return
+			default:
+			}
+
 			// Deactivate users not present in LDAP
 			if updateExisting {
 				for _, usr := range users {
diff --git a/modules/cron/cron.go b/modules/cron/cron.go
index 795fafb51f..f4511a8e79 100644
--- a/modules/cron/cron.go
+++ b/modules/cron/cron.go
@@ -6,9 +6,11 @@
 package cron
 
 import (
+	"context"
 	"time"
 
 	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/migrations"
 	"code.gitea.io/gitea/modules/setting"
@@ -37,17 +39,19 @@ var taskStatusTable = sync.NewStatusTable()
 type Func func()
 
 // WithUnique wrap a cron func with an unique running check
-func WithUnique(name string, body Func) Func {
+func WithUnique(name string, body func(context.Context)) Func {
 	return func() {
 		if !taskStatusTable.StartIfNotRunning(name) {
 			return
 		}
 		defer taskStatusTable.Stop(name)
-		body()
+		graceful.GetManager().RunWithShutdownContext(body)
 	}
 }
 
 // NewContext begins cron tasks
+// Each cron task is run within the shutdown context as a running server
+// AtShutdown the cron server is stopped
 func NewContext() {
 	var (
 		entry *cron.Entry
@@ -129,6 +133,7 @@ func NewContext() {
 	go WithUnique(updateMigrationPosterID, migrations.UpdateMigrationPosterID)()
 
 	c.Start()
+	graceful.GetManager().RunAtShutdown(context.Background(), c.Stop)
 }
 
 // ListTasks returns all running cron tasks.
diff --git a/modules/git/git.go b/modules/git/git.go
index 286e1ad8b4..d5caaa0912 100644
--- a/modules/git/git.go
+++ b/modules/git/git.go
@@ -106,7 +106,8 @@ func SetExecutablePath(path string) error {
 }
 
 // Init initializes git module
-func Init() error {
+func Init(ctx context.Context) error {
+	DefaultContext = ctx
 	// Git requires setting user.name and user.email in order to commit changes.
 	for configKey, defaultValue := range map[string]string{"user.name": "Gitea", "user.email": "gitea@fake.local"} {
 		if stdout, stderr, err := process.GetManager().Exec("git.Init(get setting)", GitExecutable, "config", "--get", configKey); err != nil || strings.TrimSpace(stdout) == "" {
diff --git a/modules/git/git_test.go b/modules/git/git_test.go
index 0c6259a9c5..27951d639b 100644
--- a/modules/git/git_test.go
+++ b/modules/git/git_test.go
@@ -5,6 +5,7 @@
 package git
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"testing"
@@ -16,7 +17,7 @@ func fatalTestError(fmtStr string, args ...interface{}) {
 }
 
 func TestMain(m *testing.M) {
-	if err := Init(); err != nil {
+	if err := Init(context.Background()); err != nil {
 		fatalTestError("Init failed: %v", err)
 	}
 
diff --git a/modules/graceful/context.go b/modules/graceful/context.go
index a4a4df7dea..1ad1109b4e 100644
--- a/modules/graceful/context.go
+++ b/modules/graceful/context.go
@@ -62,7 +62,7 @@ func (ctx *ChannelContext) Value(key interface{}) interface{} {
 // ShutdownContext returns a context.Context that is Done at shutdown
 // Callers using this context should ensure that they are registered as a running server
 // in order that they are waited for.
-func (g *gracefulManager) ShutdownContext() context.Context {
+func (g *Manager) ShutdownContext() context.Context {
 	return &ChannelContext{
 		done: g.IsShutdown(),
 		err:  ErrShutdown,
@@ -72,7 +72,7 @@ func (g *gracefulManager) ShutdownContext() context.Context {
 // HammerContext returns a context.Context that is Done at hammer
 // Callers using this context should ensure that they are registered as a running server
 // in order that they are waited for.
-func (g *gracefulManager) HammerContext() context.Context {
+func (g *Manager) HammerContext() context.Context {
 	return &ChannelContext{
 		done: g.IsHammer(),
 		err:  ErrHammer,
@@ -82,7 +82,7 @@ func (g *gracefulManager) HammerContext() context.Context {
 // TerminateContext returns a context.Context that is Done at terminate
 // Callers using this context should ensure that they are registered as a terminating server
 // in order that they are waited for.
-func (g *gracefulManager) TerminateContext() context.Context {
+func (g *Manager) TerminateContext() context.Context {
 	return &ChannelContext{
 		done: g.IsTerminate(),
 		err:  ErrTerminate,
diff --git a/modules/graceful/manager.go b/modules/graceful/manager.go
index b9a56ca9c6..eec675e297 100644
--- a/modules/graceful/manager.go
+++ b/modules/graceful/manager.go
@@ -6,9 +6,9 @@ package graceful
 
 import (
 	"context"
+	"sync"
 	"time"
 
-	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/process"
 	"code.gitea.io/gitea/modules/setting"
@@ -34,14 +34,24 @@ const (
 const numberOfServersToCreate = 3
 
 // Manager represents the graceful server manager interface
-var Manager *gracefulManager
-
-func init() {
-	Manager = newGracefulManager(context.Background())
-	// Set the git default context to the HammerContext
-	git.DefaultContext = Manager.HammerContext()
-	// Set the process default context to the HammerContext
-	process.DefaultContext = Manager.HammerContext()
+var manager *Manager
+
+var initOnce = sync.Once{}
+
+// GetManager returns the Manager
+func GetManager() *Manager {
+	InitManager(context.Background())
+	return manager
+}
+
+// InitManager creates the graceful manager in the provided context
+func InitManager(ctx context.Context) {
+	initOnce.Do(func() {
+		manager = newGracefulManager(ctx)
+
+		// Set the process default context to the HammerContext
+		process.DefaultContext = manager.HammerContext()
+	})
 }
 
 // CallbackWithContext is combined runnable and context to watch to see if the caller has finished
@@ -61,7 +71,7 @@ type RunnableWithShutdownFns func(atShutdown, atTerminate func(context.Context,
 // Please note that use of the atShutdown and atTerminate callbacks will create go-routines that will wait till their respective signals
 // - users must therefore be careful to only call these as necessary.
 // If run is not expected to run indefinitely RunWithShutdownChan is likely to be more appropriate.
-func (g *gracefulManager) RunWithShutdownFns(run RunnableWithShutdownFns) {
+func (g *Manager) RunWithShutdownFns(run RunnableWithShutdownFns) {
 	g.runningServerWaitGroup.Add(1)
 	defer g.runningServerWaitGroup.Done()
 	run(func(ctx context.Context, atShutdown func()) {
@@ -90,7 +100,7 @@ type RunnableWithShutdownChan func(atShutdown <-chan struct{}, atTerminate Callb
 // (Optionally IsHammer may be waited for instead however, this should be avoided if possible.)
 // The callback function provided to atTerminate must return once termination is complete.
 // Please note that use of the atTerminate function will create a go-routine that will wait till terminate - users must therefore be careful to only call this as necessary.
-func (g *gracefulManager) RunWithShutdownChan(run RunnableWithShutdownChan) {
+func (g *Manager) RunWithShutdownChan(run RunnableWithShutdownChan) {
 	g.runningServerWaitGroup.Add(1)
 	defer g.runningServerWaitGroup.Done()
 	run(g.IsShutdown(), func(ctx context.Context, atTerminate func()) {
@@ -101,14 +111,14 @@ func (g *gracefulManager) RunWithShutdownChan(run RunnableWithShutdownChan) {
 // RunWithShutdownContext takes a function that has a context to watch for shutdown.
 // After the provided context is Done(), the main function must return once shutdown is complete.
 // (Optionally the HammerContext may be obtained and waited for however, this should be avoided if possible.)
-func (g *gracefulManager) RunWithShutdownContext(run func(context.Context)) {
+func (g *Manager) RunWithShutdownContext(run func(context.Context)) {
 	g.runningServerWaitGroup.Add(1)
 	defer g.runningServerWaitGroup.Done()
 	run(g.ShutdownContext())
 }
 
 // RunAtTerminate adds to the terminate wait group and creates a go-routine to run the provided function at termination
-func (g *gracefulManager) RunAtTerminate(ctx context.Context, terminate func()) {
+func (g *Manager) RunAtTerminate(ctx context.Context, terminate func()) {
 	g.terminateWaitGroup.Add(1)
 	go func() {
 		select {
@@ -121,7 +131,7 @@ func (g *gracefulManager) RunAtTerminate(ctx context.Context, terminate func())
 }
 
 // RunAtShutdown creates a go-routine to run the provided function at shutdown
-func (g *gracefulManager) RunAtShutdown(ctx context.Context, shutdown func()) {
+func (g *Manager) RunAtShutdown(ctx context.Context, shutdown func()) {
 	go func() {
 		select {
 		case <-g.IsShutdown():
@@ -132,7 +142,7 @@ func (g *gracefulManager) RunAtShutdown(ctx context.Context, shutdown func()) {
 }
 
 // RunAtHammer creates a go-routine to run the provided function at shutdown
-func (g *gracefulManager) RunAtHammer(ctx context.Context, hammer func()) {
+func (g *Manager) RunAtHammer(ctx context.Context, hammer func()) {
 	go func() {
 		select {
 		case <-g.IsHammer():
@@ -141,7 +151,7 @@ func (g *gracefulManager) RunAtHammer(ctx context.Context, hammer func()) {
 		}
 	}()
 }
-func (g *gracefulManager) doShutdown() {
+func (g *Manager) doShutdown() {
 	if !g.setStateTransition(stateRunning, stateShuttingDown) {
 		return
 	}
@@ -158,48 +168,47 @@ func (g *gracefulManager) doShutdown() {
 		g.doHammerTime(0)
 		<-time.After(1 * time.Second)
 		g.doTerminate()
+		g.WaitForTerminate()
+		g.lock.Lock()
+		close(g.done)
+		g.lock.Unlock()
 	}()
 }
 
-func (g *gracefulManager) doHammerTime(d time.Duration) {
+func (g *Manager) doHammerTime(d time.Duration) {
 	time.Sleep(d)
+	g.lock.Lock()
 	select {
 	case <-g.hammer:
 	default:
 		log.Warn("Setting Hammer condition")
 		close(g.hammer)
 	}
-
+	g.lock.Unlock()
 }
 
-func (g *gracefulManager) doTerminate() {
+func (g *Manager) doTerminate() {
 	if !g.setStateTransition(stateShuttingDown, stateTerminate) {
 		return
 	}
 	g.lock.Lock()
-	close(g.terminate)
+	select {
+	case <-g.terminate:
+	default:
+		log.Warn("Terminating")
+		close(g.terminate)
+	}
 	g.lock.Unlock()
 }
 
 // IsChild returns if the current process is a child of previous Gitea process
-func (g *gracefulManager) IsChild() bool {
+func (g *Manager) IsChild() bool {
 	return g.isChild
 }
 
 // IsShutdown returns a channel which will be closed at shutdown.
 // The order of closure is IsShutdown, IsHammer (potentially), IsTerminate
-func (g *gracefulManager) IsShutdown() <-chan struct{} {
-	g.lock.RLock()
-	if g.shutdown == nil {
-		g.lock.RUnlock()
-		g.lock.Lock()
-		if g.shutdown == nil {
-			g.shutdown = make(chan struct{})
-		}
-		defer g.lock.Unlock()
-		return g.shutdown
-	}
-	defer g.lock.RUnlock()
+func (g *Manager) IsShutdown() <-chan struct{} {
 	return g.shutdown
 }
 
@@ -207,65 +216,43 @@ func (g *gracefulManager) IsShutdown() <-chan struct{} {
 // The order of closure is IsShutdown, IsHammer (potentially), IsTerminate
 // Servers running within the running server wait group should respond to IsHammer
 // if not shutdown already
-func (g *gracefulManager) IsHammer() <-chan struct{} {
-	g.lock.RLock()
-	if g.hammer == nil {
-		g.lock.RUnlock()
-		g.lock.Lock()
-		if g.hammer == nil {
-			g.hammer = make(chan struct{})
-		}
-		defer g.lock.Unlock()
-		return g.hammer
-	}
-	defer g.lock.RUnlock()
+func (g *Manager) IsHammer() <-chan struct{} {
 	return g.hammer
 }
 
 // IsTerminate returns a channel which will be closed at terminate
 // The order of closure is IsShutdown, IsHammer (potentially), IsTerminate
 // IsTerminate will only close once all running servers have stopped
-func (g *gracefulManager) IsTerminate() <-chan struct{} {
-	g.lock.RLock()
-	if g.terminate == nil {
-		g.lock.RUnlock()
-		g.lock.Lock()
-		if g.terminate == nil {
-			g.terminate = make(chan struct{})
-		}
-		defer g.lock.Unlock()
-		return g.terminate
-	}
-	defer g.lock.RUnlock()
+func (g *Manager) IsTerminate() <-chan struct{} {
 	return g.terminate
 }
 
 // ServerDone declares a running server done and subtracts one from the
 // running server wait group. Users probably do not want to call this
 // and should use one of the RunWithShutdown* functions
-func (g *gracefulManager) ServerDone() {
+func (g *Manager) ServerDone() {
 	g.runningServerWaitGroup.Done()
 }
 
 // WaitForServers waits for all running servers to finish. Users should probably
 // instead use AtTerminate or IsTerminate
-func (g *gracefulManager) WaitForServers() {
+func (g *Manager) WaitForServers() {
 	g.runningServerWaitGroup.Wait()
 }
 
 // WaitForTerminate waits for all terminating actions to finish.
 // Only the main go-routine should use this
-func (g *gracefulManager) WaitForTerminate() {
+func (g *Manager) WaitForTerminate() {
 	g.terminateWaitGroup.Wait()
 }
 
-func (g *gracefulManager) getState() state {
+func (g *Manager) getState() state {
 	g.lock.RLock()
 	defer g.lock.RUnlock()
 	return g.state
 }
 
-func (g *gracefulManager) setStateTransition(old, new state) bool {
+func (g *Manager) setStateTransition(old, new state) bool {
 	if old != g.getState() {
 		return false
 	}
@@ -279,7 +266,7 @@ func (g *gracefulManager) setStateTransition(old, new state) bool {
 	return true
 }
 
-func (g *gracefulManager) setState(st state) {
+func (g *Manager) setState(st state) {
 	g.lock.Lock()
 	defer g.lock.Unlock()
 
@@ -288,6 +275,31 @@ func (g *gracefulManager) setState(st state) {
 
 // InformCleanup tells the cleanup wait group that we have either taken a listener
 // or will not be taking a listener
-func (g *gracefulManager) InformCleanup() {
+func (g *Manager) InformCleanup() {
 	g.createServerWaitGroup.Done()
 }
+
+// Done allows the manager to be viewed as a context.Context, it returns a channel that is closed when the server is finished terminating
+func (g *Manager) Done() <-chan struct{} {
+	return g.done
+}
+
+// Err allows the manager to be viewed as a context.Context done at Terminate, it returns ErrTerminate
+func (g *Manager) Err() error {
+	select {
+	case <-g.Done():
+		return ErrTerminate
+	default:
+		return nil
+	}
+}
+
+// Value allows the manager to be viewed as a context.Context done at Terminate, it has no values
+func (g *Manager) Value(key interface{}) interface{} {
+	return nil
+}
+
+// Deadline returns nil as there is no fixed Deadline for the manager, it allows the manager to be viewed as a context.Context
+func (g *Manager) Deadline() (deadline time.Time, ok bool) {
+	return
+}
diff --git a/modules/graceful/manager_unix.go b/modules/graceful/manager_unix.go
index 1ffc59f0df..323c6a4111 100644
--- a/modules/graceful/manager_unix.go
+++ b/modules/graceful/manager_unix.go
@@ -19,7 +19,8 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 )
 
-type gracefulManager struct {
+// Manager manages the graceful shutdown process
+type Manager struct {
 	isChild                bool
 	forked                 bool
 	lock                   *sync.RWMutex
@@ -27,27 +28,37 @@ type gracefulManager struct {
 	shutdown               chan struct{}
 	hammer                 chan struct{}
 	terminate              chan struct{}
+	done                   chan struct{}
 	runningServerWaitGroup sync.WaitGroup
 	createServerWaitGroup  sync.WaitGroup
 	terminateWaitGroup     sync.WaitGroup
 }
 
-func newGracefulManager(ctx context.Context) *gracefulManager {
-	manager := &gracefulManager{
+func newGracefulManager(ctx context.Context) *Manager {
+	manager := &Manager{
 		isChild: len(os.Getenv(listenFDs)) > 0 && os.Getppid() > 1,
 		lock:    &sync.RWMutex{},
 	}
 	manager.createServerWaitGroup.Add(numberOfServersToCreate)
-	manager.Run(ctx)
+	manager.start(ctx)
 	return manager
 }
 
-func (g *gracefulManager) Run(ctx context.Context) {
+func (g *Manager) start(ctx context.Context) {
+	// Make channels
+	g.terminate = make(chan struct{})
+	g.shutdown = make(chan struct{})
+	g.hammer = make(chan struct{})
+	g.done = make(chan struct{})
+
+	// Set the running state & handle signals
 	g.setState(stateRunning)
 	go g.handleSignals(ctx)
-	c := make(chan struct{})
+
+	// Handle clean up of unused provided listeners	and delayed start-up
+	startupDone := make(chan struct{})
 	go func() {
-		defer close(c)
+		defer close(startupDone)
 		// Wait till we're done getting all of the listeners and then close
 		// the unused ones
 		g.createServerWaitGroup.Wait()
@@ -58,9 +69,19 @@ func (g *gracefulManager) Run(ctx context.Context) {
 	if setting.StartupTimeout > 0 {
 		go func() {
 			select {
-			case <-c:
+			case <-startupDone:
 				return
 			case <-g.IsShutdown():
+				func() {
+					// When waitgroup counter goes negative it will panic - we don't care about this so we can just ignore it.
+					defer func() {
+						_ = recover()
+					}()
+					// Ensure that the createServerWaitGroup stops waiting
+					for {
+						g.createServerWaitGroup.Done()
+					}
+				}()
 				return
 			case <-time.After(setting.StartupTimeout):
 				log.Error("Startup took too long! Shutting down")
@@ -70,7 +91,7 @@ func (g *gracefulManager) Run(ctx context.Context) {
 	}
 }
 
-func (g *gracefulManager) handleSignals(ctx context.Context) {
+func (g *Manager) handleSignals(ctx context.Context) {
 	signalChannel := make(chan os.Signal, 1)
 
 	signal.Notify(
@@ -123,7 +144,7 @@ func (g *gracefulManager) handleSignals(ctx context.Context) {
 	}
 }
 
-func (g *gracefulManager) doFork() error {
+func (g *Manager) doFork() error {
 	g.lock.Lock()
 	if g.forked {
 		g.lock.Unlock()
@@ -139,7 +160,9 @@ func (g *gracefulManager) doFork() error {
 	return err
 }
 
-func (g *gracefulManager) RegisterServer() {
+// RegisterServer registers the running of a listening server, in the case of unix this means that the parent process can now die.
+// Any call to RegisterServer must be matched by a call to ServerDone
+func (g *Manager) RegisterServer() {
 	KillParent()
 	g.runningServerWaitGroup.Add(1)
 }
diff --git a/modules/graceful/manager_windows.go b/modules/graceful/manager_windows.go
index 26c791e6ed..526fc0bd24 100644
--- a/modules/graceful/manager_windows.go
+++ b/modules/graceful/manager_windows.go
@@ -30,7 +30,8 @@ const (
 	acceptHammerCode = svc.Accepted(hammerCode)
 )
 
-type gracefulManager struct {
+// Manager manages the graceful shutdown process
+type Manager struct {
 	ctx                    context.Context
 	isChild                bool
 	lock                   *sync.RWMutex
@@ -38,27 +39,37 @@ type gracefulManager struct {
 	shutdown               chan struct{}
 	hammer                 chan struct{}
 	terminate              chan struct{}
+	done                   chan struct{}
 	runningServerWaitGroup sync.WaitGroup
 	createServerWaitGroup  sync.WaitGroup
 	terminateWaitGroup     sync.WaitGroup
 }
 
-func newGracefulManager(ctx context.Context) *gracefulManager {
-	manager := &gracefulManager{
+func newGracefulManager(ctx context.Context) *Manager {
+	manager := &Manager{
 		isChild: false,
 		lock:    &sync.RWMutex{},
 		ctx:     ctx,
 	}
 	manager.createServerWaitGroup.Add(numberOfServersToCreate)
-	manager.Run()
+	manager.start()
 	return manager
 }
 
-func (g *gracefulManager) Run() {
+func (g *Manager) start() {
+	// Make channels
+	g.terminate = make(chan struct{})
+	g.shutdown = make(chan struct{})
+	g.hammer = make(chan struct{})
+	g.done = make(chan struct{})
+
+	// Set the running state
 	g.setState(stateRunning)
 	if skip, _ := strconv.ParseBool(os.Getenv("SKIP_MINWINSVC")); skip {
 		return
 	}
+
+	// Make SVC process
 	run := svc.Run
 	isInteractive, err := svc.IsAnInteractiveSession()
 	if err != nil {
@@ -71,8 +82,8 @@ func (g *gracefulManager) Run() {
 	go run(WindowsServiceName, g)
 }
 
-// Execute makes gracefulManager implement svc.Handler
-func (g *gracefulManager) Execute(args []string, changes <-chan svc.ChangeRequest, status chan<- svc.Status) (svcSpecificEC bool, exitCode uint32) {
+// Execute makes Manager implement svc.Handler
+func (g *Manager) Execute(args []string, changes <-chan svc.ChangeRequest, status chan<- svc.Status) (svcSpecificEC bool, exitCode uint32) {
 	if setting.StartupTimeout > 0 {
 		status <- svc.Status{State: svc.StartPending}
 	} else {
@@ -141,11 +152,13 @@ hammerLoop:
 	return false, 0
 }
 
-func (g *gracefulManager) RegisterServer() {
+// RegisterServer registers the running of a listening server.
+// Any call to RegisterServer must be matched by a call to ServerDone
+func (g *Manager) RegisterServer() {
 	g.runningServerWaitGroup.Add(1)
 }
 
-func (g *gracefulManager) awaitServer(limit time.Duration) bool {
+func (g *Manager) awaitServer(limit time.Duration) bool {
 	c := make(chan struct{})
 	go func() {
 		defer close(c)
diff --git a/modules/graceful/net_unix.go b/modules/graceful/net_unix.go
index 5550c09f42..1e496e9d91 100644
--- a/modules/graceful/net_unix.go
+++ b/modules/graceful/net_unix.go
@@ -101,7 +101,7 @@ func CloseProvidedListeners() error {
 // creates a new one using net.Listen.
 func GetListener(network, address string) (net.Listener, error) {
 	// Add a deferral to say that we've tried to grab a listener
-	defer Manager.InformCleanup()
+	defer GetManager().InformCleanup()
 	switch network {
 	case "tcp", "tcp4", "tcp6":
 		tcpAddr, err := net.ResolveTCPAddr(network, address)
diff --git a/modules/graceful/restart_unix.go b/modules/graceful/restart_unix.go
index 3fc4f0511d..9a94e5fa67 100644
--- a/modules/graceful/restart_unix.go
+++ b/modules/graceful/restart_unix.go
@@ -22,7 +22,7 @@ var killParent sync.Once
 // KillParent sends the kill signal to the parent process if we are a child
 func KillParent() {
 	killParent.Do(func() {
-		if Manager.IsChild() {
+		if GetManager().IsChild() {
 			ppid := syscall.Getppid()
 			if ppid > 1 {
 				_ = syscall.Kill(ppid, syscall.SIGTERM)
diff --git a/modules/graceful/server.go b/modules/graceful/server.go
index c6692cbb75..30fb8cdffa 100644
--- a/modules/graceful/server.go
+++ b/modules/graceful/server.go
@@ -47,7 +47,7 @@ type Server struct {
 
 // NewServer creates a server on network at provided address
 func NewServer(network, address string) *Server {
-	if Manager.IsChild() {
+	if GetManager().IsChild() {
 		log.Info("Restarting new server: %s:%s on PID: %d", network, address, os.Getpid())
 	} else {
 		log.Info("Starting new server: %s:%s on PID: %d", network, address, os.Getpid())
@@ -138,12 +138,12 @@ func (srv *Server) ListenAndServeTLSConfig(tlsConfig *tls.Config, serve ServeFun
 func (srv *Server) Serve(serve ServeFunction) error {
 	defer log.Debug("Serve() returning... (PID: %d)", syscall.Getpid())
 	srv.setState(stateRunning)
-	Manager.RegisterServer()
+	GetManager().RegisterServer()
 	err := serve(srv.listener)
 	log.Debug("Waiting for connections to finish... (PID: %d)", syscall.Getpid())
 	srv.wg.Wait()
 	srv.setState(stateTerminate)
-	Manager.ServerDone()
+	GetManager().ServerDone()
 	// use of closed means that the listeners are closed - i.e. we should be shutting down - return nil
 	if err != nil && strings.Contains(err.Error(), "use of closed") {
 		return nil
diff --git a/modules/graceful/server_hooks.go b/modules/graceful/server_hooks.go
index 74b0fcb885..c634905711 100644
--- a/modules/graceful/server_hooks.go
+++ b/modules/graceful/server_hooks.go
@@ -14,15 +14,15 @@ import (
 // awaitShutdown waits for the shutdown signal from the Manager
 func (srv *Server) awaitShutdown() {
 	select {
-	case <-Manager.IsShutdown():
+	case <-GetManager().IsShutdown():
 		// Shutdown
 		srv.doShutdown()
-	case <-Manager.IsHammer():
+	case <-GetManager().IsHammer():
 		// Hammer
 		srv.doShutdown()
 		srv.doHammer()
 	}
-	<-Manager.IsHammer()
+	<-GetManager().IsHammer()
 	srv.doHammer()
 }
 
diff --git a/modules/indexer/code/bleve.go b/modules/indexer/code/bleve.go
index c8e1bb1879..bb2fc5bc74 100644
--- a/modules/indexer/code/bleve.go
+++ b/modules/indexer/code/bleve.go
@@ -6,6 +6,7 @@ package code
 
 import (
 	"fmt"
+	"os"
 	"strconv"
 	"strings"
 	"time"
@@ -34,10 +35,11 @@ func InitRepoIndexer() {
 		return
 	}
 	waitChannel := make(chan time.Duration)
+	// FIXME: graceful: This should use a persistable queue
 	repoIndexerOperationQueue = make(chan repoIndexerOperation, setting.Indexer.UpdateQueueLength)
 	go func() {
 		start := time.Now()
-		log.Info("Initializing Repository Indexer")
+		log.Info("PID: %d: Initializing Repository Indexer", os.Getpid())
 		initRepoIndexer(populateRepoIndexerAsynchronously)
 		go processRepoIndexerOperationQueue()
 		waitChannel <- time.Since(start)
@@ -45,7 +47,7 @@ func InitRepoIndexer() {
 	if setting.Indexer.StartupTimeout > 0 {
 		go func() {
 			timeout := setting.Indexer.StartupTimeout
-			if graceful.Manager.IsChild() && setting.GracefulHammerTime > 0 {
+			if graceful.GetManager().IsChild() && setting.GracefulHammerTime > 0 {
 				timeout += setting.GracefulHammerTime
 			}
 			select {
@@ -70,13 +72,6 @@ func populateRepoIndexerAsynchronously() error {
 		return nil
 	}
 
-	// if there is any existing repo indexer metadata in the DB, delete it
-	// since we are starting afresh. Also, xorm requires deletes to have a
-	// condition, and we want to delete everything, thus 1=1.
-	if err := models.DeleteAllRecords("repo_indexer_status"); err != nil {
-		return err
-	}
-
 	var maxRepoID int64
 	if maxRepoID, err = models.GetMaxID("repository"); err != nil {
 		return err
@@ -87,44 +82,59 @@ func populateRepoIndexerAsynchronously() error {
 
 // populateRepoIndexer populate the repo indexer with pre-existing data. This
 // should only be run when the indexer is created for the first time.
+// FIXME: graceful: This should use a persistable queue
 func populateRepoIndexer(maxRepoID int64) {
 	log.Info("Populating the repo indexer with existing repositories")
+
+	isShutdown := graceful.GetManager().IsShutdown()
+
 	// start with the maximum existing repo ID and work backwards, so that we
 	// don't include repos that are created after gitea starts; such repos will
 	// already be added to the indexer, and we don't need to add them again.
 	for maxRepoID > 0 {
-		repos := make([]*models.Repository, 0, models.RepositoryListDefaultPageSize)
-		err := models.FindByMaxID(maxRepoID, models.RepositoryListDefaultPageSize, &repos)
+		select {
+		case <-isShutdown:
+			log.Info("Repository Indexer population shutdown before completion")
+			return
+		default:
+		}
+		ids, err := models.GetUnindexedRepos(maxRepoID, 0, 50)
 		if err != nil {
 			log.Error("populateRepoIndexer: %v", err)
 			return
-		} else if len(repos) == 0 {
+		} else if len(ids) == 0 {
 			break
 		}
-		for _, repo := range repos {
+		for _, id := range ids {
+			select {
+			case <-isShutdown:
+				log.Info("Repository Indexer population shutdown before completion")
+				return
+			default:
+			}
 			repoIndexerOperationQueue <- repoIndexerOperation{
-				repoID:  repo.ID,
+				repoID:  id,
 				deleted: false,
 			}
-			maxRepoID = repo.ID - 1
+			maxRepoID = id - 1
 		}
 	}
-	log.Info("Done populating the repo indexer with existing repositories")
+	log.Info("Done (re)populating the repo indexer with existing repositories")
 }
 
 func updateRepoIndexer(repoID int64) error {
 	repo, err := models.GetRepositoryByID(repoID)
 	if err != nil {
-		return err
+		return fmt.Errorf("UpdateRepoIndexer: Unable to GetRepositoryByID: %d, Error: %v", repoID, err)
 	}
 
 	sha, err := getDefaultBranchSha(repo)
 	if err != nil {
-		return err
+		return fmt.Errorf("UpdateRepoIndexer: Unable to GetDefaultBranchSha for: %s/%s, Error: %v", repo.MustOwnerName(), repo.Name, err)
 	}
 	changes, err := getRepoChanges(repo, sha)
 	if err != nil {
-		return err
+		return fmt.Errorf("UpdateRepoIndexer: Unable to GetRepoChanges for: %s/%s Sha: %s Error: %v", repo.MustOwnerName(), repo.Name, sha, err)
 	} else if changes == nil {
 		return nil
 	}
@@ -132,16 +142,16 @@ func updateRepoIndexer(repoID int64) error {
 	batch := RepoIndexerBatch()
 	for _, update := range changes.Updates {
 		if err := addUpdate(update, repo, batch); err != nil {
-			return err
+			return fmt.Errorf("UpdateRepoIndexer: Unable to addUpdate to: %s/%s Sha: %s, update: %s(%s) Error: %v", repo.MustOwnerName(), repo.Name, sha, update.Filename, update.BlobSha, err)
 		}
 	}
 	for _, filename := range changes.RemovedFilenames {
 		if err := addDelete(filename, repo, batch); err != nil {
-			return err
+			return fmt.Errorf("UpdateRepoIndexer: Unable to addDelete to: %s/%s Sha: %s, filename: %s Error: %v", repo.MustOwnerName(), repo.Name, sha, filename, err)
 		}
 	}
 	if err = batch.Flush(); err != nil {
-		return err
+		return fmt.Errorf("UpdateRepoIndexer: Unable to flush batch to indexer for repo: %s/%s Error: %v", repo.MustOwnerName(), repo.Name, err)
 	}
 	return repo.UpdateIndexerStatus(sha)
 }
@@ -322,20 +332,26 @@ func nonGenesisChanges(repo *models.Repository, revision string) (*repoChanges,
 
 func processRepoIndexerOperationQueue() {
 	for {
-		op := <-repoIndexerOperationQueue
-		var err error
-		if op.deleted {
-			if err = deleteRepoFromIndexer(op.repoID); err != nil {
-				log.Error("deleteRepoFromIndexer: %v", err)
+		select {
+		case op := <-repoIndexerOperationQueue:
+			var err error
+			if op.deleted {
+				if err = deleteRepoFromIndexer(op.repoID); err != nil {
+					log.Error("DeleteRepoFromIndexer: %v", err)
+				}
+			} else {
+				if err = updateRepoIndexer(op.repoID); err != nil {
+					log.Error("updateRepoIndexer: %v", err)
+				}
 			}
-		} else {
-			if err = updateRepoIndexer(op.repoID); err != nil {
-				log.Error("updateRepoIndexer: %v", err)
+			for _, watcher := range op.watchers {
+				watcher <- err
 			}
+		case <-graceful.GetManager().IsShutdown():
+			log.Info("PID: %d Repository indexer queue processing stopped", os.Getpid())
+			return
 		}
-		for _, watcher := range op.watchers {
-			watcher <- err
-		}
+
 	}
 }
 
diff --git a/modules/indexer/code/repo.go b/modules/indexer/code/repo.go
index 31f0fa7f3d..bc5f317b7d 100644
--- a/modules/indexer/code/repo.go
+++ b/modules/indexer/code/repo.go
@@ -5,9 +5,13 @@
 package code
 
 import (
+	"context"
+	"os"
 	"strings"
 	"sync"
 
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 
@@ -104,21 +108,50 @@ func (update RepoIndexerUpdate) AddToFlushingBatch(batch rupture.FlushingBatch)
 func initRepoIndexer(populateIndexer func() error) {
 	indexer, err := openIndexer(setting.Indexer.RepoPath, repoIndexerLatestVersion)
 	if err != nil {
-		log.Fatal("InitRepoIndexer: %v", err)
+		log.Fatal("InitRepoIndexer %s: %v", setting.Indexer.RepoPath, err)
 	}
 	if indexer != nil {
 		indexerHolder.set(indexer)
+		closeAtTerminate()
+
+		// Continue population from where left off
+		if err = populateIndexer(); err != nil {
+			log.Fatal("PopulateRepoIndex: %v", err)
+		}
 		return
 	}
 
 	if err = createRepoIndexer(setting.Indexer.RepoPath, repoIndexerLatestVersion); err != nil {
 		log.Fatal("CreateRepoIndexer: %v", err)
 	}
+	closeAtTerminate()
+
+	// if there is any existing repo indexer metadata in the DB, delete it
+	// since we are starting afresh. Also, xorm requires deletes to have a
+	// condition, and we want to delete everything, thus 1=1.
+	if err := models.DeleteAllRecords("repo_indexer_status"); err != nil {
+		log.Fatal("DeleteAllRepoIndexerStatus: %v", err)
+	}
+
 	if err = populateIndexer(); err != nil {
 		log.Fatal("PopulateRepoIndex: %v", err)
 	}
 }
 
+func closeAtTerminate() {
+	graceful.GetManager().RunAtTerminate(context.Background(), func() {
+		log.Debug("Closing repo indexer")
+		indexer := indexerHolder.get()
+		if indexer != nil {
+			err := indexer.Close()
+			if err != nil {
+				log.Error("Error whilst closing the repository indexer: %v", err)
+			}
+		}
+		log.Info("PID: %d Repository Indexer closed", os.Getpid())
+	})
+}
+
 // createRepoIndexer create a repo indexer if one does not already exist
 func createRepoIndexer(path string, latestVersion int) error {
 	docMapping := bleve.NewDocumentMapping()
diff --git a/modules/indexer/issues/indexer.go b/modules/indexer/issues/indexer.go
index 78eba58095..50b8d6d224 100644
--- a/modules/indexer/issues/indexer.go
+++ b/modules/indexer/issues/indexer.go
@@ -172,7 +172,7 @@ func InitIssueIndexer(syncReindex bool) {
 	} else if setting.Indexer.StartupTimeout > 0 {
 		go func() {
 			timeout := setting.Indexer.StartupTimeout
-			if graceful.Manager.IsChild() && setting.GracefulHammerTime > 0 {
+			if graceful.GetManager().IsChild() && setting.GracefulHammerTime > 0 {
 				timeout += setting.GracefulHammerTime
 			}
 			select {
diff --git a/modules/migrations/update.go b/modules/migrations/update.go
index d1465b2baf..3d0962657c 100644
--- a/modules/migrations/update.go
+++ b/modules/migrations/update.go
@@ -5,21 +5,28 @@
 package migrations
 
 import (
+	"context"
+
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/structs"
 )
 
 // UpdateMigrationPosterID updates all migrated repositories' issues and comments posterID
-func UpdateMigrationPosterID() {
+func UpdateMigrationPosterID(ctx context.Context) {
 	for _, gitService := range structs.SupportedFullGitService {
-		if err := updateMigrationPosterIDByGitService(gitService); err != nil {
+		select {
+		case <-ctx.Done():
+			log.Warn("UpdateMigrationPosterID aborted due to shutdown before %s", gitService.Name())
+		default:
+		}
+		if err := updateMigrationPosterIDByGitService(ctx, gitService); err != nil {
 			log.Error("updateMigrationPosterIDByGitService failed: %v", err)
 		}
 	}
 }
 
-func updateMigrationPosterIDByGitService(tp structs.GitServiceType) error {
+func updateMigrationPosterIDByGitService(ctx context.Context, tp structs.GitServiceType) error {
 	provider := tp.Name()
 	if len(provider) == 0 {
 		return nil
@@ -28,6 +35,13 @@ func updateMigrationPosterIDByGitService(tp structs.GitServiceType) error {
 	const batchSize = 100
 	var start int
 	for {
+		select {
+		case <-ctx.Done():
+			log.Warn("UpdateMigrationPosterIDByGitService(%s) aborted due to shutdown", tp.Name())
+			return nil
+		default:
+		}
+
 		users, err := models.FindExternalUsersByProvider(models.FindExternalUserOptions{
 			Provider: provider,
 			Start:    start,
@@ -38,6 +52,12 @@ func updateMigrationPosterIDByGitService(tp structs.GitServiceType) error {
 		}
 
 		for _, user := range users {
+			select {
+			case <-ctx.Done():
+				log.Warn("UpdateMigrationPosterIDByGitService(%s) aborted due to shutdown", tp.Name())
+				return nil
+			default:
+			}
 			externalUserID := user.ExternalID
 			if err := models.UpdateMigrationsByType(tp, externalUserID, user.UserID); err != nil {
 				log.Error("UpdateMigrationsByType type %s external user id %v to local user id %v failed: %v", tp.Name(), user.ExternalID, user.UserID, err)
diff --git a/modules/ssh/ssh_graceful.go b/modules/ssh/ssh_graceful.go
index 4d7557e2ee..f8370ab4db 100644
--- a/modules/ssh/ssh_graceful.go
+++ b/modules/ssh/ssh_graceful.go
@@ -24,5 +24,5 @@ func listen(server *ssh.Server) {
 
 // Unused informs our cleanup routine that we will not be using a ssh port
 func Unused() {
-	graceful.Manager.InformCleanup()
+	graceful.GetManager().InformCleanup()
 }
diff --git a/modules/sync/unique_queue.go b/modules/sync/unique_queue.go
index de694d8560..14644c7d4e 100644
--- a/modules/sync/unique_queue.go
+++ b/modules/sync/unique_queue.go
@@ -1,4 +1,5 @@
 // Copyright 2016 The Gogs Authors. All rights reserved.
+// Copyright 2019 The Gitea Authors. All rights reserved.
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
@@ -15,8 +16,9 @@ import (
 // This queue is particularly useful for preventing duplicated task
 // of same purpose.
 type UniqueQueue struct {
-	table *StatusTable
-	queue chan string
+	table  *StatusTable
+	queue  chan string
+	closed chan struct{}
 }
 
 // NewUniqueQueue initializes and returns a new UniqueQueue object.
@@ -26,11 +28,43 @@ func NewUniqueQueue(queueLength int) *UniqueQueue {
 	}
 
 	return &UniqueQueue{
-		table: NewStatusTable(),
-		queue: make(chan string, queueLength),
+		table:  NewStatusTable(),
+		queue:  make(chan string, queueLength),
+		closed: make(chan struct{}),
 	}
 }
 
+// Close closes this queue
+func (q *UniqueQueue) Close() {
+	select {
+	case <-q.closed:
+	default:
+		q.table.lock.Lock()
+		select {
+		case <-q.closed:
+		default:
+			close(q.closed)
+		}
+		q.table.lock.Unlock()
+	}
+}
+
+// IsClosed returns a channel that is closed when this Queue is closed
+func (q *UniqueQueue) IsClosed() <-chan struct{} {
+	return q.closed
+}
+
+// IDs returns the current ids in the pool
+func (q *UniqueQueue) IDs() []interface{} {
+	q.table.lock.Lock()
+	defer q.table.lock.Unlock()
+	ids := make([]interface{}, 0, len(q.table.pool))
+	for id := range q.table.pool {
+		ids = append(ids, id)
+	}
+	return ids
+}
+
 // Queue returns channel of queue for retrieving instances.
 func (q *UniqueQueue) Queue() <-chan string {
 	return q.queue
@@ -45,18 +79,22 @@ func (q *UniqueQueue) Exist(id interface{}) bool {
 // AddFunc adds new instance to the queue with a custom runnable function,
 // the queue is blocked until the function exits.
 func (q *UniqueQueue) AddFunc(id interface{}, fn func()) {
-	if q.Exist(id) {
-		return
-	}
-
 	idStr := com.ToStr(id)
 	q.table.lock.Lock()
+	if _, ok := q.table.pool[idStr]; ok {
+		return
+	}
 	q.table.pool[idStr] = struct{}{}
 	if fn != nil {
 		fn()
 	}
 	q.table.lock.Unlock()
-	q.queue <- idStr
+	select {
+	case <-q.closed:
+		return
+	case q.queue <- idStr:
+		return
+	}
 }
 
 // Add adds new instance to the queue.
diff --git a/modules/webhook/deliver.go b/modules/webhook/deliver.go
index b262505cea..9f5c938f83 100644
--- a/modules/webhook/deliver.go
+++ b/modules/webhook/deliver.go
@@ -5,6 +5,7 @@
 package webhook
 
 import (
+	"context"
 	"crypto/tls"
 	"fmt"
 	"io/ioutil"
@@ -16,6 +17,7 @@ import (
 	"time"
 
 	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"github.com/gobwas/glob"
@@ -145,8 +147,14 @@ func Deliver(t *models.HookTask) error {
 }
 
 // DeliverHooks checks and delivers undelivered hooks.
-// TODO: shoot more hooks at same time.
-func DeliverHooks() {
+// FIXME: graceful: This would likely benefit from either a worker pool with dummy queue
+// or a full queue. Then more hooks could be sent at same time.
+func DeliverHooks(ctx context.Context) {
+	select {
+	case <-ctx.Done():
+		return
+	default:
+	}
 	tasks, err := models.FindUndeliveredHookTasks()
 	if err != nil {
 		log.Error("DeliverHooks: %v", err)
@@ -155,33 +163,50 @@ func DeliverHooks() {
 
 	// Update hook task status.
 	for _, t := range tasks {
+		select {
+		case <-ctx.Done():
+			return
+		default:
+		}
 		if err = Deliver(t); err != nil {
 			log.Error("deliver: %v", err)
 		}
 	}
 
 	// Start listening on new hook requests.
-	for repoIDStr := range hookQueue.Queue() {
-		log.Trace("DeliverHooks [repo_id: %v]", repoIDStr)
-		hookQueue.Remove(repoIDStr)
+	for {
+		select {
+		case <-ctx.Done():
+			hookQueue.Close()
+			return
+		case repoIDStr := <-hookQueue.Queue():
+			log.Trace("DeliverHooks [repo_id: %v]", repoIDStr)
+			hookQueue.Remove(repoIDStr)
 
-		repoID, err := com.StrTo(repoIDStr).Int64()
-		if err != nil {
-			log.Error("Invalid repo ID: %s", repoIDStr)
-			continue
-		}
+			repoID, err := com.StrTo(repoIDStr).Int64()
+			if err != nil {
+				log.Error("Invalid repo ID: %s", repoIDStr)
+				continue
+			}
 
-		tasks, err := models.FindRepoUndeliveredHookTasks(repoID)
-		if err != nil {
-			log.Error("Get repository [%d] hook tasks: %v", repoID, err)
-			continue
-		}
-		for _, t := range tasks {
-			if err = Deliver(t); err != nil {
-				log.Error("deliver: %v", err)
+			tasks, err := models.FindRepoUndeliveredHookTasks(repoID)
+			if err != nil {
+				log.Error("Get repository [%d] hook tasks: %v", repoID, err)
+				continue
+			}
+			for _, t := range tasks {
+				select {
+				case <-ctx.Done():
+					return
+				default:
+				}
+				if err = Deliver(t); err != nil {
+					log.Error("deliver: %v", err)
+				}
 			}
 		}
 	}
+
 }
 
 var (
@@ -234,5 +259,5 @@ func InitDeliverHooks() {
 		},
 	}
 
-	go DeliverHooks()
+	go graceful.GetManager().RunWithShutdownContext(DeliverHooks)
 }
diff --git a/routers/admin/admin.go b/routers/admin/admin.go
index 9f155ff008..ccedcaf8a6 100644
--- a/routers/admin/admin.go
+++ b/routers/admin/admin.go
@@ -19,6 +19,7 @@ import (
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/cron"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/process"
 	"code.gitea.io/gitea/modules/setting"
@@ -171,10 +172,10 @@ func Dashboard(ctx *context.Context) {
 			err = models.ReinitMissingRepositories()
 		case syncExternalUsers:
 			success = ctx.Tr("admin.dashboard.sync_external_users_started")
-			go models.SyncExternalUsers()
+			go graceful.GetManager().RunWithShutdownContext(models.SyncExternalUsers)
 		case gitFsck:
 			success = ctx.Tr("admin.dashboard.git_fsck_started")
-			go models.GitFsck()
+			go graceful.GetManager().RunWithShutdownContext(models.GitFsck)
 		case deleteGeneratedRepositoryAvatars:
 			success = ctx.Tr("admin.dashboard.delete_generated_repository_avatars_success")
 			err = models.RemoveRandomAvatars()
diff --git a/routers/init.go b/routers/init.go
index 81418a4ad5..01df15d6c5 100644
--- a/routers/init.go
+++ b/routers/init.go
@@ -5,6 +5,7 @@
 package routers
 
 import (
+	"context"
 	"strings"
 	"time"
 
@@ -53,11 +54,11 @@ func NewServices() {
 }
 
 // In case of problems connecting to DB, retry connection. Eg, PGSQL in Docker Container on Synology
-func initDBEngine() (err error) {
+func initDBEngine(ctx context.Context) (err error) {
 	log.Info("Beginning ORM engine initialization.")
 	for i := 0; i < setting.Database.DBConnectRetries; i++ {
 		log.Info("ORM engine initialization attempt #%d/%d...", i+1, setting.Database.DBConnectRetries)
-		if err = models.NewEngine(migrations.Migrate); err == nil {
+		if err = models.NewEngine(ctx, migrations.Migrate); err == nil {
 			break
 		} else if i == setting.Database.DBConnectRetries-1 {
 			return err
@@ -71,9 +72,9 @@ func initDBEngine() (err error) {
 }
 
 // GlobalInit is for global configuration reload-able.
-func GlobalInit() {
+func GlobalInit(ctx context.Context) {
 	setting.NewContext()
-	if err := git.Init(); err != nil {
+	if err := git.Init(ctx); err != nil {
 		log.Fatal("Git module init failed: %v", err)
 	}
 	setting.CheckLFSVersion()
@@ -88,7 +89,7 @@ func GlobalInit() {
 		highlight.NewContext()
 		external.RegisterParsers()
 		markup.Init()
-		if err := initDBEngine(); err == nil {
+		if err := initDBEngine(ctx); err == nil {
 			log.Info("ORM engine initialization successful!")
 		} else {
 			log.Fatal("ORM engine initialization failed: %v", err)
diff --git a/routers/install.go b/routers/install.go
index 53880d2c46..7395aeee84 100644
--- a/routers/install.go
+++ b/routers/install.go
@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/base"
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/generate"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/user"
@@ -351,7 +352,7 @@ func InstallPost(ctx *context.Context, form auth.InstallForm) {
 		return
 	}
 
-	GlobalInit()
+	GlobalInit(graceful.GetManager().HammerContext())
 
 	// Create admin account
 	if len(form.AdminName) > 0 {
diff --git a/services/mirror/mirror.go b/services/mirror/mirror.go
index 1ad9448b6b..7fc6e97b46 100644
--- a/services/mirror/mirror.go
+++ b/services/mirror/mirror.go
@@ -5,11 +5,14 @@
 package mirror
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"strings"
 	"time"
 
+	"code.gitea.io/gitea/modules/graceful"
+
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/cache"
 	"code.gitea.io/gitea/modules/git"
@@ -294,29 +297,38 @@ func Password(m *models.Mirror) string {
 }
 
 // Update checks and updates mirror repositories.
-func Update() {
+func Update(ctx context.Context) {
 	log.Trace("Doing: Update")
-
 	if err := models.MirrorsIterate(func(idx int, bean interface{}) error {
 		m := bean.(*models.Mirror)
 		if m.Repo == nil {
 			log.Error("Disconnected mirror repository found: %d", m.ID)
 			return nil
 		}
-
-		mirrorQueue.Add(m.RepoID)
-		return nil
+		select {
+		case <-ctx.Done():
+			return fmt.Errorf("Aborted due to shutdown")
+		default:
+			mirrorQueue.Add(m.RepoID)
+			return nil
+		}
 	}); err != nil {
 		log.Error("Update: %v", err)
 	}
 }
 
 // SyncMirrors checks and syncs mirrors.
-// TODO: sync more mirrors at same time.
-func SyncMirrors() {
+// FIXME: graceful: this should be a persistable queue
+func SyncMirrors(ctx context.Context) {
 	// Start listening on new sync requests.
-	for repoID := range mirrorQueue.Queue() {
-		syncMirror(repoID)
+	for {
+		select {
+		case <-ctx.Done():
+			mirrorQueue.Close()
+			return
+		case repoID := <-mirrorQueue.Queue():
+			syncMirror(repoID)
+		}
 	}
 }
 
@@ -416,7 +428,7 @@ func syncMirror(repoID string) {
 
 // InitSyncMirrors initializes a go routine to sync the mirrors
 func InitSyncMirrors() {
-	go SyncMirrors()
+	go graceful.GetManager().RunWithShutdownContext(SyncMirrors)
 }
 
 // StartToMirror adds repoID to mirror queue
diff --git a/services/pull/check.go b/services/pull/check.go
index fc2ac927b8..7344f071ac 100644
--- a/services/pull/check.go
+++ b/services/pull/check.go
@@ -6,6 +6,7 @@
 package pull
 
 import (
+	"context"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -16,6 +17,7 @@ import (
 
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/sync"
@@ -151,65 +153,53 @@ func manuallyMerged(pr *models.PullRequest) bool {
 
 // TestPullRequests checks and tests untested patches of pull requests.
 // TODO: test more pull requests at same time.
-func TestPullRequests() {
-	prs, err := models.GetPullRequestsByCheckStatus(models.PullRequestStatusChecking)
-	if err != nil {
-		log.Error("Find Checking PRs: %v", err)
-		return
-	}
-
-	var checkedPRs = make(map[int64]struct{})
+func TestPullRequests(ctx context.Context) {
 
-	// Update pull request status.
-	for _, pr := range prs {
-		checkedPRs[pr.ID] = struct{}{}
-		if err := pr.GetBaseRepo(); err != nil {
-			log.Error("GetBaseRepo: %v", err)
-			continue
-		}
-		if manuallyMerged(pr) {
-			continue
+	go func() {
+		prs, err := models.GetPullRequestIDsByCheckStatus(models.PullRequestStatusChecking)
+		if err != nil {
+			log.Error("Find Checking PRs: %v", err)
+			return
 		}
-		if err := TestPatch(pr); err != nil {
-			log.Error("testPatch: %v", err)
-			continue
+		for _, prID := range prs {
+			select {
+			case <-ctx.Done():
+				return
+			default:
+				pullRequestQueue.Add(prID)
+			}
 		}
-
-		checkAndUpdateStatus(pr)
-	}
+	}()
 
 	// Start listening on new test requests.
-	for prID := range pullRequestQueue.Queue() {
-		log.Trace("TestPullRequests[%v]: processing test task", prID)
-		pullRequestQueue.Remove(prID)
-
-		id := com.StrTo(prID).MustInt64()
-		if _, ok := checkedPRs[id]; ok {
-			continue
-		}
-
-		pr, err := models.GetPullRequestByID(id)
-		if err != nil {
-			log.Error("GetPullRequestByID[%s]: %v", prID, err)
-			continue
-		} else if manuallyMerged(pr) {
-			continue
-		}
-		pr.Status = models.PullRequestStatusChecking
-		if err := pr.Update(); err != nil {
-			log.Error("testPatch[%d]: Unable to update status to Checking Status %v", pr.ID, err)
-			continue
-		}
-		if err = TestPatch(pr); err != nil {
-			log.Error("testPatch[%d]: %v", pr.ID, err)
-			continue
+	for {
+		select {
+		case prID := <-pullRequestQueue.Queue():
+			log.Trace("TestPullRequests[%v]: processing test task", prID)
+			pullRequestQueue.Remove(prID)
+
+			id := com.StrTo(prID).MustInt64()
+
+			pr, err := models.GetPullRequestByID(id)
+			if err != nil {
+				log.Error("GetPullRequestByID[%s]: %v", prID, err)
+				continue
+			} else if manuallyMerged(pr) {
+				continue
+			} else if err = TestPatch(pr); err != nil {
+				log.Error("testPatch[%d]: %v", pr.ID, err)
+				continue
+			}
+			checkAndUpdateStatus(pr)
+		case <-ctx.Done():
+			pullRequestQueue.Close()
+			log.Info("PID: %d Pull Request testing shutdown", os.Getpid())
+			return
 		}
-
-		checkAndUpdateStatus(pr)
 	}
 }
 
 // Init runs the task queue to test all the checking status pull requests
 func Init() {
-	go TestPullRequests()
+	go graceful.GetManager().RunWithShutdownContext(TestPullRequests)
 }
diff --git a/services/pull/pull.go b/services/pull/pull.go
index 6447c8a87f..e7f4e4eede 100644
--- a/services/pull/pull.go
+++ b/services/pull/pull.go
@@ -5,12 +5,14 @@
 package pull
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"path"
 
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/notification"
 	issue_service "code.gitea.io/gitea/services/issue"
@@ -54,6 +56,7 @@ func checkForInvalidation(requests models.PullRequestList, repoID int64, doer *m
 		return fmt.Errorf("git.OpenRepository: %v", err)
 	}
 	go func() {
+		// FIXME: graceful: We need to tell the manager we're doing something...
 		err := requests.InvalidateCodeComments(doer, gitRepo, branch)
 		if err != nil {
 			log.Error("PullRequestList.InvalidateCodeComments: %v", err)
@@ -79,39 +82,45 @@ func addHeadRepoTasks(prs []*models.PullRequest) {
 // and generate new patch for testing as needed.
 func AddTestPullRequestTask(doer *models.User, repoID int64, branch string, isSync bool) {
 	log.Trace("AddTestPullRequestTask [head_repo_id: %d, head_branch: %s]: finding pull requests", repoID, branch)
-	prs, err := models.GetUnmergedPullRequestsByHeadInfo(repoID, branch)
-	if err != nil {
-		log.Error("Find pull requests [head_repo_id: %d, head_branch: %s]: %v", repoID, branch, err)
-		return
-	}
+	graceful.GetManager().RunWithShutdownContext(func(ctx context.Context) {
+		// There is no sensible way to shut this down ":-("
+		// If you don't let it run all the way then you will lose data
+		// FIXME: graceful: AddTestPullRequestTask needs to become a queue!
 
-	if isSync {
-		requests := models.PullRequestList(prs)
-		if err = requests.LoadAttributes(); err != nil {
-			log.Error("PullRequestList.LoadAttributes: %v", err)
-		}
-		if invalidationErr := checkForInvalidation(requests, repoID, doer, branch); invalidationErr != nil {
-			log.Error("checkForInvalidation: %v", invalidationErr)
+		prs, err := models.GetUnmergedPullRequestsByHeadInfo(repoID, branch)
+		if err != nil {
+			log.Error("Find pull requests [head_repo_id: %d, head_branch: %s]: %v", repoID, branch, err)
+			return
 		}
-		if err == nil {
-			for _, pr := range prs {
-				pr.Issue.PullRequest = pr
-				notification.NotifyPullRequestSynchronized(doer, pr)
+
+		if isSync {
+			requests := models.PullRequestList(prs)
+			if err = requests.LoadAttributes(); err != nil {
+				log.Error("PullRequestList.LoadAttributes: %v", err)
+			}
+			if invalidationErr := checkForInvalidation(requests, repoID, doer, branch); invalidationErr != nil {
+				log.Error("checkForInvalidation: %v", invalidationErr)
+			}
+			if err == nil {
+				for _, pr := range prs {
+					pr.Issue.PullRequest = pr
+					notification.NotifyPullRequestSynchronized(doer, pr)
+				}
 			}
 		}
-	}
 
-	addHeadRepoTasks(prs)
+		addHeadRepoTasks(prs)
 
-	log.Trace("AddTestPullRequestTask [base_repo_id: %d, base_branch: %s]: finding pull requests", repoID, branch)
-	prs, err = models.GetUnmergedPullRequestsByBaseInfo(repoID, branch)
-	if err != nil {
-		log.Error("Find pull requests [base_repo_id: %d, base_branch: %s]: %v", repoID, branch, err)
-		return
-	}
-	for _, pr := range prs {
-		AddToTaskQueue(pr)
-	}
+		log.Trace("AddTestPullRequestTask [base_repo_id: %d, base_branch: %s]: finding pull requests", repoID, branch)
+		prs, err = models.GetUnmergedPullRequestsByBaseInfo(repoID, branch)
+		if err != nil {
+			log.Error("Find pull requests [base_repo_id: %d, base_branch: %s]: %v", repoID, branch, err)
+			return
+		}
+		for _, pr := range prs {
+			AddToTaskQueue(pr)
+		}
+	})
 }
 
 // PushToBaseRepo pushes commits from branches of head repository to