ddl: fix unstable test TestCreateDropCreateTable

pkg/ddl/ddl.go

@@ -874,6 +874,7 @@ func (d *ddl) Start(ctxPool *pools.ResourcePool) error {
 		if ingest.LitBackCtxMgr != nil {
 			ingest.LitBackCtxMgr.MarkJobFinish()
 		}
+		d.runningJobs = newRunningJobs()
 	})
 
 	return nil

pkg/ddl/ddl_running_jobs.go

@@ -28,57 +28,96 @@ import (
 
 type runningJobs struct {
 	sync.RWMutex
-	ids           map[int64]struct{}
-	runningSchema map[string]map[string]struct{} // database -> table -> struct{}
-	runningJobIDs string
+	// processingIDs records the IDs of the jobs that are being processed by a worker.
+	processingIDs    map[int64]struct{}
+	processingIDsStr string
+
+	// unfinishedIDs records the IDs of the jobs that are not finished yet.
+	// It is not necessarily being processed by a worker.
+	unfinishedIDs    map[int64]struct{}
+	unfinishedSchema map[string]map[string]struct{} // database -> table -> struct{}
 }
 
 func newRunningJobs() *runningJobs {
 	return &runningJobs{
-		ids:           make(map[int64]struct{}),
-		runningSchema: make(map[string]map[string]struct{}),
+		processingIDs:    make(map[int64]struct{}),
+		unfinishedSchema: make(map[string]map[string]struct{}),
+		unfinishedIDs:    make(map[int64]struct{}),
 	}
 }
 
 func (j *runningJobs) add(job *model.Job) {
 	j.Lock()
 	defer j.Unlock()
-	j.ids[job.ID] = struct{}{}
+	j.processingIDs[job.ID] = struct{}{}
 	j.updateInternalRunningJobIDs()
+
+	if _, ok := j.unfinishedIDs[job.ID]; ok {
+		// Already exists, no need to add it again.
+		return
+	}
+	j.unfinishedIDs[job.ID] = struct{}{}
 	for _, info := range job.GetInvolvingSchemaInfo() {
-		if _, ok := j.runningSchema[info.Database]; !ok {
-			j.runningSchema[info.Database] = make(map[string]struct{})
+		if _, ok := j.unfinishedSchema[info.Database]; !ok {
+			j.unfinishedSchema[info.Database] = make(map[string]struct{})
 		}
-		j.runningSchema[info.Database][info.Table] = struct{}{}
+		j.unfinishedSchema[info.Database][info.Table] = struct{}{}
 	}
 }
 
 func (j *runningJobs) remove(job *model.Job) {
 	j.Lock()
 	defer j.Unlock()
-	delete(j.ids, job.ID)
+	delete(j.processingIDs, job.ID)
 	j.updateInternalRunningJobIDs()
-	for _, info := range job.GetInvolvingSchemaInfo() {
-		if db, ok := j.runningSchema[info.Database]; ok {
-			delete(db, info.Table)
+
+	if job.IsFinished() || job.IsSynced() {
+		delete(j.unfinishedIDs, job.ID)
+		for _, info := range job.GetInvolvingSchemaInfo() {
+			if db, ok := j.unfinishedSchema[info.Database]; ok {
+				delete(db, info.Table)
+			}
+			if len(j.unfinishedSchema[info.Database]) == 0 {
+				delete(j.unfinishedSchema, info.Database)
+			}
 		}
-		if len(j.runningSchema[info.Database]) == 0 {
-			delete(j.runningSchema, info.Database)
+	}
+}
+
+func (j *runningJobs) allIDs() string {
+	j.RLock()
+	defer j.RUnlock()
+	return j.processingIDsStr
+}
+
+func (j *runningJobs) updateInternalRunningJobIDs() {
+	var sb strings.Builder
+	i := 0
+	for id := range j.processingIDs {
+		sb.WriteString(strconv.Itoa(int(id)))
+		if i != len(j.processingIDs)-1 {
+			sb.WriteString(",")
 		}
+		i++
 	}
+	j.processingIDsStr = sb.String()
 }
 
 func (j *runningJobs) checkRunnable(job *model.Job) bool {
 	j.RLock()
 	defer j.RUnlock()
+	if _, ok := j.processingIDs[job.ID]; ok {
+		// Already processing by a worker. Skip running it again.
+		return false
+	}
 	for _, info := range job.GetInvolvingSchemaInfo() {
-		if _, ok := j.runningSchema[model.InvolvingAll]; ok {
+		if _, ok := j.unfinishedSchema[model.InvolvingAll]; ok {
 			return false
 		}
 		if info.Database == model.InvolvingNone {
 			continue
 		}
-		if tbls, ok := j.runningSchema[info.Database]; ok {
+		if tbls, ok := j.unfinishedSchema[info.Database]; ok {
 			if _, ok := tbls[model.InvolvingAll]; ok {
 				return false
 			}
@@ -92,22 +131,3 @@ func (j *runningJobs) checkRunnable(job *model.Job) bool {
 	}
 	return true
 }
-
-func (j *runningJobs) allIDs() string {
-	j.RLock()
-	defer j.RUnlock()
-	return j.runningJobIDs
-}
-
-func (j *runningJobs) updateInternalRunningJobIDs() {
-	var sb strings.Builder
-	i := 0
-	for id := range j.ids {
-		sb.WriteString(strconv.Itoa(int(id)))
-		if i != len(j.ids)-1 {
-			sb.WriteString(",")
-		}
-		i++
-	}
-	j.runningJobIDs = sb.String()
-}