[comparison] initial implementation

- handle new task types: cluster_comparison, index_comparison - handle new pipeline tasks: dump_hash, index_diff - split common task APIs - add cluster_comparison task creation API - optimize & clean migration codes
2023-05-17 15:43:04 +08:00 · 2023-05-17 15:43:04 +08:00 · 7e79c509b2
parent 79bf42c775
commit 7e79c509b2
16 changed files with 1591 additions and 402 deletions
--- a/model/notification.go
+++ b/model/notification.go
@ -14,9 +14,10 @@ const (
 type MessageType string

 const (
-	MessageTypeNews      MessageType = "news"
-	MessageTypeAlerting  MessageType = "alerting"
-	MessageTypeMigration MessageType = "migration"
+	MessageTypeNews       MessageType = "news"
+	MessageTypeAlerting   MessageType = "alerting"
+	MessageTypeMigration  MessageType = "migration"
+	MessageTypeComparison MessageType = "comparison"
 )

 type NotificationStatus string
--- a/plugin/migration/api.go
+++ b/plugin/migration/api.go
@ -6,10 +6,8 @@ package migration

 import (
 	"context"
-	"errors"
 	"fmt"
 	"net/http"
-	"strconv"
 	"strings"
 	"time"

@ -28,32 +26,35 @@ import (
 	"infini.sh/framework/core/orm"
 	task2 "infini.sh/framework/core/task"
 	"infini.sh/framework/core/util"
-	elastic2 "infini.sh/framework/modules/elastic"
 )

 func InitAPI() {
 	handler := APIHandler{}
-	api.HandleAPIMethod(api.GET, "/migration/data/_search", handler.RequirePermission(handler.searchDataMigrationTask, enum.PermissionTaskRead))
+	api.HandleAPIMethod(api.GET, "/migration/data/_search", handler.RequirePermission(handler.searchTask("cluster_migration"), enum.PermissionTaskRead))
 	api.HandleAPIMethod(api.POST, "/migration/data", handler.RequirePermission(handler.createDataMigrationTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.DELETE, "/migration/data/:task_id", handler.RequirePermission(handler.deleteTask, enum.PermissionTaskWrite))
 	api.HandleAPIMethod(api.POST, "/migration/data/_validate", handler.RequireLogin(handler.validateDataMigration))
+	api.HandleAPIMethod(api.POST, "/migration/data/:task_id/_start", handler.RequirePermission(handler.startTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.POST, "/migration/data/:task_id/_stop", handler.RequirePermission(handler.stopTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.GET, "/migration/data/:task_id/info", handler.RequirePermission(handler.getDataMigrationTaskInfo, enum.PermissionTaskRead))
+	api.HandleAPIMethod(api.GET, "/migration/data/:task_id/info/:index", handler.RequirePermission(handler.getDataMigrationTaskOfIndex, enum.PermissionTaskRead))
+	api.HandleAPIMethod(api.PUT, "/migration/data/:task_id/status", handler.RequirePermission(handler.updateDataMigrationTaskStatus, enum.PermissionTaskRead))
+
+	api.HandleAPIMethod(api.GET, "/comparison/data/_search", handler.RequirePermission(handler.searchTask("cluster_comparison"), enum.PermissionTaskRead))
+	api.HandleAPIMethod(api.POST, "/comparison/data", handler.RequirePermission(handler.createDataComparisonTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.DELETE, "/comparison/data/:task_id", handler.RequirePermission(handler.deleteTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.POST, "/comparison/data/:task_id/_start", handler.RequirePermission(handler.startTask, enum.PermissionTaskWrite))
+	api.HandleAPIMethod(api.POST, "/comparison/data/:task_id/_stop", handler.RequirePermission(handler.stopTask, enum.PermissionTaskWrite))

 	api.HandleAPIMethod(api.POST, "/elasticsearch/:id/index/:index/_partition", handler.getIndexPartitionInfo)
 	api.HandleAPIMethod(api.POST, "/elasticsearch/:id/index/:index/_count", handler.countDocuments)
 	api.HandleAPIMethod(api.POST, "/elasticsearch/:id/index/:index/_refresh", handler.refreshIndex)
-	api.HandleAPIMethod(api.POST, "/migration/data/:task_id/_start", handler.RequirePermission(handler.startDataMigration, enum.PermissionTaskWrite))
-	api.HandleAPIMethod(api.POST, "/migration/data/:task_id/_stop", handler.RequirePermission(handler.stopDataMigrationTask, enum.PermissionTaskWrite))
-	//api.HandleAPIMethod(api.GET, "/migration/data/:task_id", handler.getMigrationTask)
-	api.HandleAPIMethod(api.GET, "/migration/data/:task_id/info", handler.RequirePermission(handler.getDataMigrationTaskInfo, enum.PermissionTaskRead))
-	api.HandleAPIMethod(api.GET, "/migration/data/:task_id/info/:index", handler.RequirePermission(handler.getDataMigrationTaskOfIndex, enum.PermissionTaskRead))
-	api.HandleAPIMethod(api.PUT, "/migration/data/:task_id/status", handler.RequirePermission(handler.updateDataMigrationTaskStatus, enum.PermissionTaskRead))
 	api.HandleAPIMethod(api.POST, "/elasticsearch/:id/index/:index/_init", handler.initIndex)
-	api.HandleAPIMethod(api.DELETE, "/migration/data/:task_id", handler.deleteDataMigrationTask)

 }

 type APIHandler struct {
 	api.Handler
-	bulkResultIndexName string
 }

 func (h *APIHandler) createDataMigrationTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
@ -113,96 +114,6 @@ func (h *APIHandler) createDataMigrationTask(w http.ResponseWriter, req *http.Re
 	h.WriteCreatedOKJSON(w, t.ID)
 }

-func (h *APIHandler) searchDataMigrationTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
-	var (
-		keyword = h.GetParameterOrDefault(req, "keyword", "")
-		strSize = h.GetParameterOrDefault(req, "size", "20")
-		strFrom = h.GetParameterOrDefault(req, "from", "0")
-		mustQ   []interface{}
-	)
-	mustQ = append(mustQ, util.MapStr{
-		"term": util.MapStr{
-			"metadata.type": util.MapStr{
-				"value": "cluster_migration",
-			},
-		},
-	})
-
-	if keyword != "" {
-		mustQ = append(mustQ, util.MapStr{
-			"query_string": util.MapStr{
-				"default_field": "*",
-				"query":         keyword,
-			},
-		})
-	}
-	size, _ := strconv.Atoi(strSize)
-	if size <= 0 {
-		size = 20
-	}
-	from, _ := strconv.Atoi(strFrom)
-	if from < 0 {
-		from = 0
-	}
-
-	queryDSL := util.MapStr{
-		"sort": []util.MapStr{
-			{
-				"created": util.MapStr{
-					"order": "desc",
-				},
-			},
-		},
-		"size": size,
-		"from": from,
-		"query": util.MapStr{
-			"bool": util.MapStr{
-				"must": mustQ,
-			},
-		},
-	}
-
-	q := orm.Query{}
-	q.RawQuery = util.MustToJSONBytes(queryDSL)
-
-	err, res := orm.Search(&task2.Task{}, &q)
-	if err != nil {
-		log.Error(err)
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		return
-	}
-
-	searchRes := &elastic.SearchResponse{}
-	err = util.FromJSONBytes(res.Raw, searchRes)
-	if err != nil {
-		log.Error(err)
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		return
-	}
-	for _, hit := range searchRes.Hits.Hits {
-		sourceM := util.MapStr(hit.Source)
-		buf := util.MustToJSONBytes(sourceM["config"])
-		dataConfig := migration_model.ClusterMigrationTaskConfig{}
-		err = util.FromJSONBytes(buf, &dataConfig)
-		if err != nil {
-			log.Error(err)
-			continue
-		}
-		//var targetTotalDocs int64
-		if hit.Source["status"] == task2.StatusRunning {
-			ts, err := getMajorTaskStatsFromInstances(hit.ID)
-			if err != nil {
-				log.Warnf("fetch progress info of task error: %v", err)
-				continue
-			}
-			sourceM.Put("metadata.labels.target_total_docs", ts.IndexDocs)
-		}
-
-	}
-
-	h.WriteJSON(w, searchRes, http.StatusOK)
-}
-
 func (h *APIHandler) getIndexPartitionInfo(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
 	var (
 		index     = ps.MustGetParameter("index")
@ -227,92 +138,6 @@ func (h *APIHandler) getIndexPartitionInfo(w http.ResponseWriter, req *http.Requ
 	h.WriteJSON(w, partitions, http.StatusOK)
 }

-func (h *APIHandler) startDataMigration(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
-	taskID := ps.MustGetParameter("task_id")
-	obj := task2.Task{}
-
-	obj.ID = taskID
-	exists, err := orm.Get(&obj)
-	if !exists || err != nil {
-		h.WriteError(w, fmt.Sprintf("task [%s] not found", taskID), http.StatusInternalServerError)
-		return
-	}
-	if obj.Metadata.Type != "pipeline" && obj.Status == task2.StatusComplete {
-		h.WriteError(w, fmt.Sprintf("[%s] task [%s] completed, can't start anymore", obj.Metadata.Type, taskID), http.StatusInternalServerError)
-		return
-	}
-	obj.Status = task2.StatusReady
-
-	err = orm.Update(nil, &obj)
-	if err != nil {
-		log.Error(err)
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		return
-	}
-
-	migration_util.WriteLog(&obj, &task2.TaskResult{
-		Success: true,
-	}, "task status manually set to ready")
-
-	// update status of parent task to running
-	for _, parentTaskID := range obj.ParentId {
-		parentTask := task2.Task{}
-		parentTask.ID = parentTaskID
-		exists, err := orm.Get(&parentTask)
-		if !exists || err != nil {
-			h.WriteError(w, fmt.Sprintf("parent task [%s] not found", parentTaskID), http.StatusInternalServerError)
-			return
-		}
-		parentTask.Status = task2.StatusRunning
-		err = orm.Update(nil, &parentTask)
-		if err != nil {
-			log.Error(err)
-			h.WriteError(w, err.Error(), http.StatusInternalServerError)
-			return
-		}
-		migration_util.WriteLog(&parentTask, nil, fmt.Sprintf("child [%s] task [%s] manually started", obj.Metadata.Type, taskID))
-	}
-
-	h.WriteJSON(w, util.MapStr{
-		"success": true,
-	}, 200)
-}
-
-func (h *APIHandler) stopDataMigrationTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
-	id := ps.MustGetParameter("task_id")
-	obj := task2.Task{}
-	obj.ID = id
-
-	exists, err := orm.Get(&obj)
-	if !exists || err != nil {
-		h.WriteJSON(w, util.MapStr{
-			"_id":   id,
-			"found": false,
-		}, http.StatusNotFound)
-		return
-	}
-	if task2.IsEnded(obj.Status) {
-		h.WriteJSON(w, util.MapStr{
-			"success": true,
-		}, 200)
-		return
-	}
-	obj.Status = task2.StatusPendingStop
-	err = orm.Update(nil, &obj)
-	if err != nil {
-		log.Error(err)
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		return
-	}
-	migration_util.WriteLog(&obj, &task2.TaskResult{
-		Success: true,
-	}, "task status manually set to pending stop")
-
-	h.WriteJSON(w, util.MapStr{
-		"success": true,
-	}, 200)
-}
-
 func getIndexRefreshInterval(indexNames []string, targetESClient elastic.API) (map[string]string, error) {
 	const step = 50
 	var (
@ -806,28 +631,6 @@ func (h *APIHandler) getDataMigrationTaskOfIndex(w http.ResponseWriter, req *htt
 	h.WriteJSON(w, taskInfo, http.StatusOK)
 }

-func (h *APIHandler) getMigrationTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
-	id := ps.MustGetParameter("task_id")
-
-	obj := task2.Task{}
-	obj.ID = id
-
-	exists, err := orm.Get(&obj)
-	if !exists || err != nil {
-		h.WriteJSON(w, util.MapStr{
-			"_id":   id,
-			"found": false,
-		}, http.StatusNotFound)
-		return
-	}
-
-	h.WriteJSON(w, util.MapStr{
-		"found":   true,
-		"_id":     id,
-		"_source": obj,
-	}, 200)
-}
-
 func (h *APIHandler) countDocuments(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
 	var (
 		index     = ps.MustGetParameter("index")
@ -1008,65 +811,6 @@ func (h *APIHandler) initIndex(w http.ResponseWriter, req *http.Request, ps http
 	}, http.StatusOK)
 }

-func (h *APIHandler) deleteDataMigrationTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
-	id := ps.MustGetParameter("task_id")
-	obj := task2.Task{}
-	obj.ID = id
-
-	_, err := orm.Get(&obj)
-	if err != nil {
-		if errors.Is(err, elastic2.ErrNotFound) {
-			h.WriteJSON(w, util.MapStr{
-				"_id":    id,
-				"result": "not_found",
-			}, http.StatusNotFound)
-			return
-		}
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		log.Error(err)
-		return
-	}
-	if util.StringInArray([]string{task2.StatusReady, task2.StatusRunning, task2.StatusPendingStop}, obj.Status) {
-		h.WriteError(w, fmt.Sprintf("can not delete task [%s] with status [%s]", obj.ID, obj.Status), http.StatusInternalServerError)
-		return
-	}
-
-	q := util.MapStr{
-		"query": util.MapStr{
-			"bool": util.MapStr{
-				"minimum_should_match": 1,
-				"should": []util.MapStr{
-					{
-						"term": util.MapStr{
-							"parent_id": util.MapStr{
-								"value": id,
-							},
-						},
-					},
-					{
-						"term": util.MapStr{
-							"id": util.MapStr{
-								"value": id,
-							},
-						},
-					},
-				},
-			},
-		},
-	}
-	err = orm.DeleteBy(&obj, util.MustToJSONBytes(q))
-	if err != nil {
-		h.WriteError(w, err.Error(), http.StatusInternalServerError)
-		log.Error(err)
-		return
-	}
-
-	h.WriteJSON(w, util.MapStr{
-		"_id":    obj.ID,
-		"result": "deleted",
-	}, 200)
-}
-
 func (h *APIHandler) refreshIndex(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
 	var (
 		index     = ps.MustGetParameter("index")
--- a/plugin/migration/cluster_comparison/cluster_comparison.go
+++ b/plugin/migration/cluster_comparison/cluster_comparison.go
@ -0,0 +1,410 @@
+package cluster_comparison
+
+import (
+	"fmt"
+	"time"
+
+	log "github.com/cihub/seelog"
+	"infini.sh/console/model"
+	migration_model "infini.sh/console/plugin/migration/model"
+	migration_util "infini.sh/console/plugin/migration/util"
+
+	"infini.sh/framework/core/elastic"
+	"infini.sh/framework/core/orm"
+	"infini.sh/framework/core/task"
+	"infini.sh/framework/core/util"
+)
+
+type processor struct {
+	Elasticsearch string
+	IndexName     string
+	scheduler     migration_model.Scheduler
+}
+
+func NewProcessor(elasticsearch, indexName string, scheduler migration_model.Scheduler) migration_model.Processor {
+	return &processor{
+		Elasticsearch: elasticsearch,
+		IndexName:     indexName,
+		scheduler:     scheduler,
+	}
+}
+
+func (p *processor) Process(t *task.Task) (err error) {
+	switch t.Status {
+	case task.StatusReady:
+		// split & schedule index_comparison tasks
+		err = p.handleReadyMajorTask(t)
+	case task.StatusRunning:
+		// check index_comparison tasks status
+		err = p.handleRunningMajorTask(t)
+	case task.StatusPendingStop:
+		// mark index_comparison as pending_stop
+		err = p.handlePendingStopMajorTask(t)
+	}
+	return err
+}
+
+func (p *processor) handleReadyMajorTask(taskItem *task.Task) error {
+	if ok, _ := util.ExtractBool(taskItem.Metadata.Labels["is_split"]); !ok {
+		return p.splitMajorTask(taskItem)
+	}
+	//update status of subtask to ready
+	query := util.MapStr{
+		"bool": util.MapStr{
+			"must": []util.MapStr{
+				{
+					"term": util.MapStr{
+						"parent_id": util.MapStr{
+							"value": taskItem.ID,
+						},
+					},
+				},
+				{
+					"terms": util.MapStr{
+						"status": []string{task.StatusError, task.StatusStopped},
+					},
+				},
+				{
+					"term": util.MapStr{
+						"metadata.type": util.MapStr{
+							"value": "index_comparison",
+						},
+					},
+				},
+			},
+		},
+	}
+	queryDsl := util.MapStr{
+		"query": query,
+		"script": util.MapStr{
+			"source": fmt.Sprintf("ctx._source['status'] = '%s'", task.StatusReady),
+		},
+	}
+
+	esClient := elastic.GetClient(p.Elasticsearch)
+	_, err := esClient.UpdateByQuery(p.IndexName, util.MustToJSONBytes(queryDsl))
+	if err != nil {
+		log.Errorf("failed to update sub task status, err: %v", err)
+		return nil
+	}
+	taskItem.RetryTimes++
+	taskItem.Status = task.StatusRunning
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: true,
+	}, fmt.Sprintf("cluster comparison task [%s] started", taskItem.ID))
+	p.sendMajorTaskNotification(taskItem)
+	return nil
+}
+
+func (p *processor) splitMajorTask(taskItem *task.Task) error {
+	clusterComparisonTask := migration_model.ClusterComparisonTaskConfig{}
+	err := migration_util.GetTaskConfig(taskItem, &clusterComparisonTask)
+	if err != nil {
+		log.Errorf("failed to get task config, err: %v", err)
+		return err
+	}
+	esSourceClient := elastic.GetClient(clusterComparisonTask.Cluster.Source.Id)
+
+	for _, index := range clusterComparisonTask.Indices {
+		sourceDump := migration_model.IndexComparisonDumpConfig{
+			ClusterId:     clusterComparisonTask.Cluster.Source.Id,
+			Indices:       index.Source.Name,
+			SliceSize:     clusterComparisonTask.Settings.Dump.SliceSize,
+			BatchSize:     clusterComparisonTask.Settings.Dump.Docs,
+			PartitionSize: clusterComparisonTask.Settings.Dump.PartitionSize,
+			ScrollTime:    clusterComparisonTask.Settings.Dump.Timeout,
+		}
+		// TODO: dump_hash can only handle 1G file
+		if sourceDump.PartitionSize <= 0 {
+			sourceDump.PartitionSize = 1
+		}
+
+		if v, ok := index.RawFilter.(string); ok {
+			sourceDump.QueryString = v
+		} else {
+			var must []interface{}
+			if index.RawFilter != nil {
+				must = append(must, index.RawFilter)
+			}
+			if len(must) > 0 {
+				sourceDump.QueryDSL = util.MapStr{
+					"bool": util.MapStr{
+						"must": must,
+					},
+				}
+			}
+		}
+
+		if index.Partition != nil {
+			partitionQ := &elastic.PartitionQuery{
+				IndexName: index.Source.Name,
+				FieldName: index.Partition.FieldName,
+				FieldType: index.Partition.FieldType,
+				Step:      index.Partition.Step,
+			}
+			if sourceDump.QueryDSL != nil {
+				partitionQ.Filter = sourceDump.QueryDSL
+			}
+			partitions, err := elastic.GetPartitions(partitionQ, esSourceClient)
+			if err != nil {
+				return err
+			}
+			if partitions == nil || len(partitions) == 0 {
+				return fmt.Errorf("empty data with filter: %s", util.MustToJSON(index.RawFilter))
+			}
+			for _, partition := range partitions {
+				//skip empty partition
+				if partition.Docs <= 0 {
+					continue
+				}
+				partitionSourceDump := sourceDump
+				partitionSourceDump.QueryDSL = partition.Filter
+				partitionSourceDump.DocCount = partition.Docs
+				partitionSourceDump.QueryString = ""
+
+				// TODO: if there's a partition missing from source but present in target
+				// ideally we can capture it in docs count, but this won't always work
+				partitionTargetDump := partitionSourceDump
+				partitionTargetDump.Indices = index.Target.Name
+
+				partitionComparisonTask := task.Task{
+					ParentId:    []string{taskItem.ID},
+					Cancellable: false,
+					Runnable:    true,
+					Status:      task.StatusReady,
+					Metadata: task.Metadata{
+						Type: "index_comparison",
+						Labels: util.MapStr{
+							"business_id":       "index_comparison",
+							"source_cluster_id": clusterComparisonTask.Cluster.Source.Id,
+							"target_cluster_id": clusterComparisonTask.Cluster.Target.Id,
+							"index_name":        index.Source.Name,
+							"unique_index_name": index.Source.GetUniqueIndexName(),
+						},
+					},
+					ConfigString: util.MustToJSON(migration_model.IndexComparisonTaskConfig{
+						Source:    partitionSourceDump,
+						Target:    partitionTargetDump,
+						Execution: clusterComparisonTask.Settings.Execution,
+					}),
+				}
+				partitionComparisonTask.ID = util.GetUUID()
+				err = orm.Create(nil, &partitionComparisonTask)
+				if err != nil {
+					return fmt.Errorf("store index comparison task (partition) error: %w", err)
+				}
+
+			}
+		} else {
+			sourceDump.DocCount = index.Source.Docs
+			targetDump := sourceDump
+			targetDump.Indices = index.Target.Name
+
+			indexComparisonTask := task.Task{
+				ParentId:    []string{taskItem.ID},
+				Cancellable: true,
+				Runnable:    false,
+				Status:      task.StatusReady,
+				Metadata: task.Metadata{
+					Type: "index_comparison",
+					Labels: util.MapStr{
+						"business_id":       "index_comparison",
+						"source_cluster_id": clusterComparisonTask.Cluster.Source.Id,
+						"target_cluster_id": clusterComparisonTask.Cluster.Target.Id,
+						"partition_count":   1,
+						"index_name":        index.Source.Name,
+						"unique_index_name": index.Source.GetUniqueIndexName(),
+					},
+				},
+				ConfigString: util.MustToJSON(migration_model.IndexComparisonTaskConfig{
+					Source:    sourceDump,
+					Target:    targetDump,
+					Execution: clusterComparisonTask.Settings.Execution,
+				}),
+			}
+			indexComparisonTask.ID = util.GetUUID()
+
+			err = orm.Create(nil, &indexComparisonTask)
+			if err != nil {
+				return fmt.Errorf("store index comparison task error: %w", err)
+			}
+		}
+	}
+
+	taskItem.Metadata.Labels["is_split"] = true
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: true,
+	}, fmt.Sprintf("major task [%s] splitted", taskItem.ID))
+	return nil
+}
+
+func (p *processor) handleRunningMajorTask(taskItem *task.Task) error {
+	taskStatus, err := p.getMajorTaskState(taskItem)
+	if err != nil {
+		return err
+	}
+	if !(taskStatus == task.StatusComplete || taskStatus == task.StatusError) {
+		return nil
+	}
+
+	var errMsg string
+
+	if taskStatus == task.StatusError {
+		errMsg = "index comparison(s) failed"
+	}
+
+	if errMsg == "" {
+		taskItem.Status = task.StatusComplete
+	} else {
+		taskItem.Status = task.StatusError
+	}
+	tn := time.Now()
+	taskItem.CompletedTime = &tn
+	p.sendMajorTaskNotification(taskItem)
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: errMsg == "",
+		Error:   errMsg,
+	}, fmt.Sprintf("cluster comparison task [%s] finished with status [%s]", taskItem.ID, taskItem.Status))
+	return nil
+}
+
+func (p *processor) getMajorTaskState(majorTask *task.Task) (string, error) {
+	query := util.MapStr{
+		"size": 0,
+		"aggs": util.MapStr{
+			"count": util.MapStr{
+				"terms": util.MapStr{
+					"field": "*",
+				},
+			},
+			"grp": util.MapStr{
+				"terms": util.MapStr{
+					"field": "status",
+				},
+			},
+		},
+		"query": util.MapStr{
+			"bool": util.MapStr{
+				"must": []util.MapStr{
+					{
+						"term": util.MapStr{
+							"parent_id": util.MapStr{
+								"value": majorTask.ID,
+							},
+						},
+					},
+					{
+						"term": util.MapStr{
+							"metadata.type": util.MapStr{
+								"value": "index_comparison",
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+	esClient := elastic.GetClient(p.Elasticsearch)
+	res, err := esClient.SearchWithRawQueryDSL(p.IndexName, util.MustToJSONBytes(query))
+	if err != nil {
+		log.Errorf("search es failed, err: %v", err)
+		return "", nil
+	}
+	var (
+		hasError bool
+	)
+	for _, bk := range res.Aggregations["grp"].Buckets {
+		statusKey, _ := util.ExtractString(bk["key"])
+		if migration_util.IsRunningState(statusKey) {
+			return task.StatusRunning, nil
+		}
+		if statusKey == task.StatusError {
+			hasError = true
+		}
+	}
+	if hasError {
+		return task.StatusError, nil
+	}
+	return task.StatusComplete, nil
+}
+
+func (p *processor) handlePendingStopMajorTask(taskItem *task.Task) error {
+	err := migration_util.UpdatePendingChildTasksToPendingStop(taskItem, "index_comparison")
+	if err != nil {
+		log.Errorf("failed to update sub task status, err: %v", err)
+		return nil
+	}
+
+	tasks, err := migration_util.GetPendingChildTasks(p.Elasticsearch, p.IndexName, taskItem.ID, "index_comparison")
+	if err != nil {
+		log.Errorf("failed to get sub tasks, err: %v", err)
+		return nil
+	}
+
+	// all subtask stopped or error or complete
+	if len(tasks) == 0 {
+		taskItem.Status = task.StatusStopped
+		p.sendMajorTaskNotification(taskItem)
+		p.saveTaskAndWriteLog(taskItem, nil, fmt.Sprintf("cluster comparison task [%s] stopped", taskItem.ID))
+		// NOTE: we don't know how many running index_comparison's stopped, so do a refresh from ES
+		p.scheduler.RefreshInstanceJobsFromES()
+	}
+	return nil
+}
+
+func (p *processor) saveTaskAndWriteLog(taskItem *task.Task, taskResult *task.TaskResult, message string) {
+	esClient := elastic.GetClient(p.Elasticsearch)
+	_, err := esClient.Index(p.IndexName, "", taskItem.ID, taskItem, "")
+	if err != nil {
+		log.Errorf("failed to update task, err: %v", err)
+	}
+	if message != "" {
+		migration_util.WriteLog(taskItem, taskResult, message)
+	}
+}
+
+func (p *processor) sendMajorTaskNotification(taskItem *task.Task) {
+	config := migration_model.ClusterComparisonTaskConfig{}
+	err := migration_util.GetTaskConfig(taskItem, &config)
+	if err != nil {
+		log.Errorf("failed to parse config info from major task, id: %s, err: %v", taskItem.ID, err)
+		return
+	}
+
+	creatorID := config.Creator.Id
+
+	var title, body string
+	body = fmt.Sprintf("From Cluster: [%s (%s)], To Cluster: [%s (%s)]", config.Cluster.Source.Id, config.Cluster.Source.Name, config.Cluster.Target.Id, config.Cluster.Target.Name)
+	link := fmt.Sprintf("/#/data_tools/comparison/%s/detail", taskItem.ID)
+	switch taskItem.Status {
+	case task.StatusReady:
+		log.Debugf("skip sending notification for ready task, id: %s", taskItem.ID)
+		return
+	case task.StatusStopped:
+		title = fmt.Sprintf("Data Comparison Stopped")
+	case task.StatusComplete:
+		title = fmt.Sprintf("Data Comparison Completed")
+	case task.StatusError:
+		title = fmt.Sprintf("Data Comparison Failed")
+	case task.StatusRunning:
+		title = fmt.Sprintf("Data Comparison Started")
+	default:
+		log.Warnf("skip sending notification for invalid task status, id: %s", taskItem.ID)
+		return
+	}
+	notification := &model.Notification{
+		UserId:      util.ToString(creatorID),
+		Type:        model.NotificationTypeNotification,
+		MessageType: model.MessageTypeComparison,
+		Status:      model.NotificationStatusNew,
+		Title:       title,
+		Body:        body,
+		Link:        link,
+	}
+	err = orm.Create(nil, notification)
+	if err != nil {
+		log.Errorf("failed to create notification, err: %v", err)
+		return
+	}
+	return
+}
--- a/plugin/migration/cluster_migration/cluster_migration.go
+++ b/plugin/migration/cluster_migration/cluster_migration.go
@ -34,13 +34,13 @@ func NewProcessor(elasticsearch, indexName string, scheduler migration_model.Sch
 func (p *processor) Process(t *task.Task) (err error) {
 	switch t.Status {
 	case task.StatusReady:
-		// mark index_migrations as pending_stop
+		// split & schedule index_migration tasks
 		err = p.handleReadyMajorTask(t)
 	case task.StatusRunning:
 		// check index_migration tasks status
 		err = p.handleRunningMajorTask(t)
 	case task.StatusPendingStop:
-		// split & schedule index_migration tasks
+		// mark index_migrations as pending_stop
 		err = p.handlePendingStopMajorTask(t)
 	}
 	return err
@ -105,9 +105,6 @@ func (p *processor) splitMajorMigrationTask(taskItem *task.Task) error {
 		log.Errorf("failed to get task config, err: %v", err)
 		return err
 	}
-	defer func() {
-		taskItem.ConfigString = util.MustToJSON(clusterMigrationTask)
-	}()
 	esSourceClient := elastic.GetClient(clusterMigrationTask.Cluster.Source.Id)
 	targetType := common.GetClusterDocType(clusterMigrationTask.Cluster.Target.Id)

@ -164,17 +161,6 @@ func (p *processor) splitMajorMigrationTask(taskItem *task.Task) error {
 				}
 			}
 		}
-		var targetMust []interface{}
-		if index.RawFilter != nil {
-			targetMust = append(targetMust, index.RawFilter)
-		}
-		if index.Target.DocType != "" && targetType != "" {
-			targetMust = append(targetMust, util.MapStr{
-				"terms": util.MapStr{
-					"_type": []string{index.Target.DocType},
-				},
-			})
-		}

 		target := migration_model.IndexMigrationTargetConfig{
 			ClusterId: clusterMigrationTask.Cluster.Target.Id,
@ -255,18 +241,11 @@ func (p *processor) splitMajorMigrationTask(taskItem *task.Task) error {
 		} else {
 			source.DocCount = index.Source.Docs

-			indexParameters := migration_model.IndexMigrationTaskConfig{
-				Source:    source,
-				Target:    target,
-				Execution: clusterMigrationTask.Settings.Execution,
-				Version:   migration_model.IndexMigrationV1,
-			}
 			indexMigrationTask := task.Task{
-				ParentId:          []string{taskItem.ID},
-				Cancellable:       true,
-				Runnable:          false,
-				Status:            task.StatusReady,
-				StartTimeInMillis: time.Now().UnixMilli(),
+				ParentId:    []string{taskItem.ID},
+				Cancellable: true,
+				Runnable:    false,
+				Status:      task.StatusReady,
 				Metadata: task.Metadata{
 					Type: "index_migration",
 					Labels: util.MapStr{
@ -278,7 +257,12 @@ func (p *processor) splitMajorMigrationTask(taskItem *task.Task) error {
 						"unique_index_name": index.Source.GetUniqueIndexName(),
 					},
 				},
-				ConfigString: util.MustToJSON(indexParameters),
+				ConfigString: util.MustToJSON(migration_model.IndexMigrationTaskConfig{
+					Source:    source,
+					Target:    target,
+					Execution: clusterMigrationTask.Settings.Execution,
+					Version:   migration_model.IndexMigrationV1,
+				}),
 			}

 			indexMigrationTask.ID = util.GetUUID()
--- a/plugin/migration/common_api.go
+++ b/plugin/migration/common_api.go
@ -0,0 +1,258 @@
+package migration
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"strconv"
+
+	log "github.com/cihub/seelog"
+
+	migration_model "infini.sh/console/plugin/migration/model"
+	migration_util "infini.sh/console/plugin/migration/util"
+
+	httprouter "infini.sh/framework/core/api/router"
+	"infini.sh/framework/core/elastic"
+	"infini.sh/framework/core/orm"
+	"infini.sh/framework/core/task"
+	"infini.sh/framework/core/util"
+	elastic2 "infini.sh/framework/modules/elastic"
+)
+
+func (h *APIHandler) searchTask(taskType string) func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+		var (
+			keyword = h.GetParameterOrDefault(req, "keyword", "")
+			strSize = h.GetParameterOrDefault(req, "size", "20")
+			strFrom = h.GetParameterOrDefault(req, "from", "0")
+			mustQ   []interface{}
+		)
+		mustQ = append(mustQ, util.MapStr{
+			"term": util.MapStr{
+				"metadata.type": util.MapStr{
+					"value": taskType,
+				},
+			},
+		})
+
+		if keyword != "" {
+			mustQ = append(mustQ, util.MapStr{
+				"query_string": util.MapStr{
+					"default_field": "*",
+					"query":         keyword,
+				},
+			})
+		}
+		size, _ := strconv.Atoi(strSize)
+		if size <= 0 {
+			size = 20
+		}
+		from, _ := strconv.Atoi(strFrom)
+		if from < 0 {
+			from = 0
+		}
+
+		queryDSL := util.MapStr{
+			"sort": []util.MapStr{
+				{
+					"created": util.MapStr{
+						"order": "desc",
+					},
+				},
+			},
+			"size": size,
+			"from": from,
+			"query": util.MapStr{
+				"bool": util.MapStr{
+					"must": mustQ,
+				},
+			},
+		}
+
+		q := orm.Query{}
+		q.RawQuery = util.MustToJSONBytes(queryDSL)
+
+		err, res := orm.Search(&task.Task{}, &q)
+		if err != nil {
+			log.Error(err)
+			h.WriteError(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		searchRes := &elastic.SearchResponse{}
+		err = util.FromJSONBytes(res.Raw, searchRes)
+		if err != nil {
+			log.Error(err)
+			h.WriteError(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		for _, hit := range searchRes.Hits.Hits {
+			sourceM := util.MapStr(hit.Source)
+			buf := util.MustToJSONBytes(sourceM["config"])
+			dataConfig := migration_model.ClusterMigrationTaskConfig{}
+			err = util.FromJSONBytes(buf, &dataConfig)
+			if err != nil {
+				log.Error(err)
+				continue
+			}
+			//var targetTotalDocs int64
+			if hit.Source["status"] == task.StatusRunning {
+				ts, err := getMajorTaskStatsFromInstances(hit.ID)
+				if err != nil {
+					log.Warnf("fetch progress info of task error: %v", err)
+					continue
+				}
+				sourceM.Put("metadata.labels.target_total_docs", ts.IndexDocs)
+			}
+
+		}
+
+		h.WriteJSON(w, searchRes, http.StatusOK)
+	}
+}
+
+func (h *APIHandler) startTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+	taskID := ps.MustGetParameter("task_id")
+	obj := task.Task{}
+
+	obj.ID = taskID
+	exists, err := orm.Get(&obj)
+	if !exists || err != nil {
+		h.WriteError(w, fmt.Sprintf("task [%s] not found", taskID), http.StatusInternalServerError)
+		return
+	}
+	if obj.Metadata.Type != "pipeline" && obj.Status == task.StatusComplete {
+		h.WriteError(w, fmt.Sprintf("[%s] task [%s] completed, can't start anymore", obj.Metadata.Type, taskID), http.StatusInternalServerError)
+		return
+	}
+	obj.Status = task.StatusReady
+
+	err = orm.Update(nil, &obj)
+	if err != nil {
+		log.Error(err)
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	migration_util.WriteLog(&obj, &task.TaskResult{
+		Success: true,
+	}, "task status manually set to ready")
+
+	// update status of parent task to running
+	for _, parentTaskID := range obj.ParentId {
+		parentTask := task.Task{}
+		parentTask.ID = parentTaskID
+		exists, err := orm.Get(&parentTask)
+		if !exists || err != nil {
+			h.WriteError(w, fmt.Sprintf("parent task [%s] not found", parentTaskID), http.StatusInternalServerError)
+			return
+		}
+		parentTask.Status = task.StatusRunning
+		err = orm.Update(nil, &parentTask)
+		if err != nil {
+			log.Error(err)
+			h.WriteError(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		migration_util.WriteLog(&parentTask, nil, fmt.Sprintf("child [%s] task [%s] manually started", obj.Metadata.Type, taskID))
+	}
+
+	h.WriteJSON(w, util.MapStr{
+		"success": true,
+	}, 200)
+}
+
+func (h *APIHandler) stopTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+	id := ps.MustGetParameter("task_id")
+	obj := task.Task{}
+	obj.ID = id
+
+	exists, err := orm.Get(&obj)
+	if !exists || err != nil {
+		h.WriteJSON(w, util.MapStr{
+			"_id":   id,
+			"found": false,
+		}, http.StatusNotFound)
+		return
+	}
+	if task.IsEnded(obj.Status) {
+		h.WriteJSON(w, util.MapStr{
+			"success": true,
+		}, 200)
+		return
+	}
+	obj.Status = task.StatusPendingStop
+	err = orm.Update(nil, &obj)
+	if err != nil {
+		log.Error(err)
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	migration_util.WriteLog(&obj, &task.TaskResult{
+		Success: true,
+	}, "task status manually set to pending stop")
+
+	h.WriteJSON(w, util.MapStr{
+		"success": true,
+	}, 200)
+}
+
+// delete task and all sub tasks
+func (h *APIHandler) deleteTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+	id := ps.MustGetParameter("task_id")
+	obj := task.Task{}
+	obj.ID = id
+
+	_, err := orm.Get(&obj)
+	if err != nil {
+		if errors.Is(err, elastic2.ErrNotFound) {
+			h.WriteJSON(w, util.MapStr{
+				"_id":    id,
+				"result": "not_found",
+			}, http.StatusNotFound)
+			return
+		}
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		log.Error(err)
+		return
+	}
+	if util.StringInArray([]string{task.StatusReady, task.StatusRunning, task.StatusPendingStop}, obj.Status) {
+		h.WriteError(w, fmt.Sprintf("can not delete task [%s] with status [%s]", obj.ID, obj.Status), http.StatusInternalServerError)
+		return
+	}
+
+	q := util.MapStr{
+		"query": util.MapStr{
+			"bool": util.MapStr{
+				"minimum_should_match": 1,
+				"should": []util.MapStr{
+					{
+						"term": util.MapStr{
+							"parent_id": util.MapStr{
+								"value": id,
+							},
+						},
+					},
+					{
+						"term": util.MapStr{
+							"id": util.MapStr{
+								"value": id,
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+	err = orm.DeleteBy(&obj, util.MustToJSONBytes(q))
+	if err != nil {
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		log.Error(err)
+		return
+	}
+
+	h.WriteJSON(w, util.MapStr{
+		"_id":    obj.ID,
+		"result": "deleted",
+	}, 200)
+}
--- a/plugin/migration/comparison_api.go
+++ b/plugin/migration/comparison_api.go
@ -0,0 +1,73 @@
+package migration
+
+import (
+	"net/http"
+
+	log "github.com/cihub/seelog"
+
+	migration_model "infini.sh/console/plugin/migration/model"
+
+	"infini.sh/framework/core/api/rbac"
+	httprouter "infini.sh/framework/core/api/router"
+	"infini.sh/framework/core/elastic"
+	"infini.sh/framework/core/orm"
+	"infini.sh/framework/core/task"
+	"infini.sh/framework/core/util"
+)
+
+func (h *APIHandler) createDataComparisonTask(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+	clusterTaskConfig := &migration_model.ClusterComparisonTaskConfig{}
+	err := h.DecodeJSON(req, clusterTaskConfig)
+	if err != nil {
+		log.Error(err)
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if len(clusterTaskConfig.Indices) == 0 {
+		h.WriteError(w, "indices must not be empty", http.StatusInternalServerError)
+		return
+	}
+	user, err := rbac.FromUserContext(req.Context())
+	if err != nil {
+		log.Error(err)
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if user != nil {
+		clusterTaskConfig.Creator.Name = user.Username
+		clusterTaskConfig.Creator.Id = user.UserId
+	}
+
+	var totalDocs int64
+	for _, index := range clusterTaskConfig.Indices {
+		totalDocs += index.Source.Docs
+	}
+
+	srcClusterCfg := elastic.GetConfig(clusterTaskConfig.Cluster.Source.Id)
+	clusterTaskConfig.Cluster.Source.Distribution = srcClusterCfg.Distribution
+	dstClusterCfg := elastic.GetConfig(clusterTaskConfig.Cluster.Target.Id)
+	clusterTaskConfig.Cluster.Target.Distribution = dstClusterCfg.Distribution
+	t := task.Task{
+		Metadata: task.Metadata{
+			Type: "cluster_comparison",
+			Labels: util.MapStr{
+				"business_id":       "cluster_comparison",
+				"source_cluster_id": clusterTaskConfig.Cluster.Source.Id,
+				"target_cluster_id": clusterTaskConfig.Cluster.Target.Id,
+				"source_total_docs": totalDocs,
+			},
+		},
+		Cancellable:  true,
+		Runnable:     false,
+		Status:       task.StatusInit,
+		ConfigString: util.MustToJSON(clusterTaskConfig),
+	}
+	t.ID = util.GetUUID()
+	err = orm.Create(nil, &t)
+	if err != nil {
+		h.WriteError(w, err.Error(), http.StatusInternalServerError)
+		log.Error(err)
+		return
+	}
+	h.WriteCreatedOKJSON(w, t.ID)
+}
--- a/plugin/migration/index_comparison/index_comparison.go
+++ b/plugin/migration/index_comparison/index_comparison.go
@ -0,0 +1,480 @@
+package index_comparison
+
+import (
+	"fmt"
+	"time"
+
+	log "github.com/cihub/seelog"
+	"infini.sh/console/model"
+	migration_model "infini.sh/console/plugin/migration/model"
+	migration_util "infini.sh/console/plugin/migration/util"
+
+	"infini.sh/framework/core/elastic"
+	"infini.sh/framework/core/orm"
+	"infini.sh/framework/core/task"
+	"infini.sh/framework/core/util"
+)
+
+type processor struct {
+	Elasticsearch string
+	IndexName     string
+	scheduler     migration_model.Scheduler
+}
+
+func NewProcessor(elasticsearch, indexName string, scheduler migration_model.Scheduler) migration_model.Processor {
+	return &processor{
+		Elasticsearch: elasticsearch,
+		IndexName:     indexName,
+		scheduler:     scheduler,
+	}
+}
+
+func (p *processor) Process(t *task.Task) (err error) {
+	switch t.Status {
+	case task.StatusReady:
+		// split & schedule pipline tasks
+		err = p.handleReadySubTask(t)
+	case task.StatusRunning:
+		// check pipeline tasks status
+		err = p.handleRunningSubTask(t)
+	case task.StatusPendingStop:
+		// mark pipeline tasks as pending_stop
+		err = p.handlePendingStopSubTask(t)
+	}
+	return err
+}
+
+func (p *processor) handleReadySubTask(taskItem *task.Task) error {
+	if ok, _ := util.ExtractBool(taskItem.Metadata.Labels["is_split"]); !ok {
+		return p.handleSplitSubTask(taskItem)
+	}
+
+	return p.handleScheduleSubTask(taskItem)
+}
+
+// split task to two dump_hash and on index_diff pipeline and then persistent
+func (p *processor) handleSplitSubTask(taskItem *task.Task) error {
+	cfg := migration_model.IndexComparisonTaskConfig{}
+	err := migration_util.GetTaskConfig(taskItem, &cfg)
+	if err != nil {
+		return fmt.Errorf("got wrong config [%v] with task [%s], err: %v", taskItem.ConfigString, taskItem.ID, err)
+	}
+
+	if len(taskItem.ParentId) == 0 {
+		return fmt.Errorf("got wrong parent id of task [%v]", *taskItem)
+	}
+
+	var pids []string
+	pids = append(pids, taskItem.ParentId...)
+	pids = append(pids, taskItem.ID)
+	sourceClusterID := cfg.Source.ClusterId
+	targetClusterID := cfg.Target.ClusterId
+
+	sourceDumpID := util.GetUUID()
+	sourceDumpTask := &task.Task{
+		ParentId:    pids,
+		Runnable:    true,
+		Cancellable: true,
+		Metadata: task.Metadata{
+			Type: "pipeline",
+			Labels: util.MapStr{
+				"cluster_id":        sourceClusterID,
+				"pipeline_id":       "dump_hash",
+				"index_name":        cfg.Source.Indices,
+				"unique_index_name": taskItem.Metadata.Labels["unique_index_name"],
+			},
+		},
+		Status:     task.StatusInit,
+		RetryTimes: taskItem.RetryTimes,
+		ConfigString: util.MustToJSON(migration_model.PipelineTaskConfig{
+			Name: sourceDumpID,
+			Logging: migration_model.PipelineTaskLoggingConfig{
+				Enabled: true,
+			},
+			Labels: util.MapStr{
+				"parent_task_id":    pids,
+				"unique_index_name": taskItem.Metadata.Labels["unique_index_name"],
+			},
+			AutoStart:   true,
+			KeepRunning: false,
+			Processor: []util.MapStr{
+				{
+					"dump_hash": util.MapStr{
+						"slice_size":      cfg.Source.SliceSize,
+						"batch_size":      cfg.Source.BatchSize,
+						"indices":         cfg.Source.Indices,
+						"elasticsearch":   sourceClusterID,
+						"output_queue":    sourceDumpID,
+						"clean_old_files": true,
+						"partition_size":  cfg.Source.PartitionSize,
+						"scroll_time":     cfg.Source.ScrollTime,
+						"query_dsl": util.MustToJSON(util.MapStr{
+							"query": cfg.Source.QueryDSL,
+						}),
+					},
+				},
+			},
+		}),
+	}
+	sourceDumpTask.ID = sourceDumpID
+
+	targetDumpID := util.GetUUID()
+	targetDumpTask := &task.Task{
+		ParentId:    pids,
+		Runnable:    true,
+		Cancellable: true,
+		Metadata: task.Metadata{
+			Type: "pipeline",
+			Labels: util.MapStr{
+				"cluster_id":        targetClusterID,
+				"pipeline_id":       "dump_hash",
+				"index_name":        cfg.Target.Indices,
+				"unique_index_name": taskItem.Metadata.Labels["unique_index_name"],
+			},
+		},
+		Status:     task.StatusInit,
+		RetryTimes: taskItem.RetryTimes,
+		ConfigString: util.MustToJSON(migration_model.PipelineTaskConfig{
+			Name: targetDumpID,
+			Logging: migration_model.PipelineTaskLoggingConfig{
+				Enabled: true,
+			},
+			Labels: util.MapStr{
+				"parent_task_id":    pids,
+				"unique_index_name": taskItem.Metadata.Labels["unique_index_name"],
+			},
+			AutoStart:   true,
+			KeepRunning: false,
+			Processor: []util.MapStr{
+				{
+					"dump_hash": util.MapStr{
+						"slice_size":      cfg.Target.SliceSize,
+						"batch_size":      cfg.Target.BatchSize,
+						"indices":         cfg.Target.Indices,
+						"elasticsearch":   targetClusterID,
+						"output_queue":    targetDumpID,
+						"clean_old_files": true,
+						"partition_size":  cfg.Target.PartitionSize,
+						"scroll_time":     cfg.Target.ScrollTime,
+						"query_dsl": util.MustToJSON(util.MapStr{
+							"query": cfg.Target.QueryDSL,
+						}),
+					},
+				},
+			},
+		}),
+	}
+	targetDumpTask.ID = targetDumpID
+
+	diffID := util.GetUUID()
+	diffTask := &task.Task{
+		ParentId:    pids,
+		Runnable:    true,
+		Cancellable: true,
+		Metadata: task.Metadata{
+			Type: "pipeline",
+			Labels: util.MapStr{
+				"pipeline_id": "index_diff",
+			},
+		},
+		Status:     task.StatusInit,
+		RetryTimes: taskItem.RetryTimes,
+		ConfigString: util.MustToJSON(migration_model.PipelineTaskConfig{
+			Name: diffID,
+			Logging: migration_model.PipelineTaskLoggingConfig{
+				Enabled: true,
+			},
+			Labels: util.MapStr{
+				"parent_task_id":    pids,
+				"unique_index_name": taskItem.Metadata.Labels["unique_index_name"],
+			},
+			AutoStart:   true,
+			KeepRunning: false,
+			Processor: []util.MapStr{
+				{
+					"index_diff": util.MapStr{
+						"text_report":     false,
+						"keep_source":     false,
+						"buffer_size":     1,
+						"clean_old_files": true,
+						// NOTE: source & target must have same partition_size
+						"partition_size": cfg.Source.PartitionSize,
+						"source_queue":   sourceDumpID,
+						"target_queue":   targetDumpID,
+						"output_queue": util.MapStr{
+							"name": diffID,
+							"labels": util.MapStr{
+								"comparison_task_id": taskItem.ID,
+							},
+						},
+					},
+				},
+			},
+		}),
+	}
+	diffTask.ID = diffID
+
+	err = orm.Create(nil, sourceDumpTask)
+	if err != nil {
+		return fmt.Errorf("create source dump pipeline task error: %w", err)
+	}
+	err = orm.Create(nil, targetDumpTask)
+	if err != nil {
+		return fmt.Errorf("create target dump pipeline task error: %w", err)
+	}
+	err = orm.Create(nil, diffTask)
+	if err != nil {
+		return fmt.Errorf("create diff pipeline task error: %w", err)
+	}
+
+	taskItem.Metadata.Labels["is_split"] = true
+	taskItem.Status = task.StatusReady
+
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: true,
+	}, fmt.Sprintf("comparison task [%s] splitted", taskItem.ID))
+	return nil
+}
+
+func (p *processor) handleScheduleSubTask(taskItem *task.Task) error {
+	cfg := migration_model.IndexComparisonTaskConfig{}
+	err := migration_util.GetTaskConfig(taskItem, &cfg)
+	if err != nil {
+		log.Errorf("failed to get task config, err: %v", err)
+		return fmt.Errorf("got wrong config of task [%s]", taskItem.ID)
+	}
+
+	sourceDumpTask, targetDumpTask, diffTask, err := p.getPipelineTasks(taskItem, &cfg)
+	if err != nil {
+		log.Errorf("failed to get pipeline tasks, err: %v", err)
+		return nil
+	}
+	if sourceDumpTask == nil || targetDumpTask == nil || diffTask == nil {
+		// ES might not synced yet
+		log.Warnf("task [%s] pipeline task(s) not found", taskItem.ID)
+		return nil
+	}
+
+	taskItem.RetryTimes++
+
+	// get a new instanceID
+	executionConfig := cfg.Execution
+	instance, err := p.scheduler.GetPreferenceInstance(executionConfig)
+	if err != nil {
+		if err == migration_model.ErrHitMax {
+			log.Debug("hit max tasks per instance, skip dispatch")
+			return nil
+		}
+		return fmt.Errorf("get preference intance error: %w", err)
+	}
+	instanceID := instance.ID
+
+	// try to clear disk queue before running dump_hash
+	p.cleanGatewayQueue(taskItem)
+
+	sourceDumpTask.RetryTimes = taskItem.RetryTimes
+	sourceDumpTask.Status = task.StatusReady
+	err = orm.Update(nil, sourceDumpTask)
+	if err != nil {
+		return fmt.Errorf("update source dump pipeline task error: %w", err)
+	}
+	targetDumpTask.RetryTimes = taskItem.RetryTimes
+	targetDumpTask.Status = task.StatusReady
+	err = orm.Update(nil, targetDumpTask)
+	if err != nil {
+		return fmt.Errorf("update target dump pipeline task error: %w", err)
+	}
+	diffTask.RetryTimes = taskItem.RetryTimes
+	diffTask.Status = task.StatusInit
+	err = orm.Update(nil, diffTask)
+	if err != nil {
+		return fmt.Errorf("update diff pipeline task error: %w", err)
+	}
+
+	// update sub migration task status to running and save task log
+	taskItem.Metadata.Labels["execution_instance_id"] = instanceID
+	taskItem.Status = task.StatusRunning
+	taskItem.StartTimeInMillis = time.Now().UnixMilli()
+
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: true,
+	}, fmt.Sprintf("index comparison task [%s] started", taskItem.ID))
+	// update dispatcher state
+	p.scheduler.IncrInstanceJobs(instanceID)
+	return nil
+}
+
+func (p *processor) handleRunningSubTask(taskItem *task.Task) error {
+	cfg := migration_model.IndexComparisonTaskConfig{}
+	err := migration_util.GetTaskConfig(taskItem, &cfg)
+	if err != nil {
+		log.Errorf("failed to get task config, err: %v", err)
+		return fmt.Errorf("got wrong config of task [%s]", taskItem.ID)
+	}
+	instanceID, _ := util.ExtractString(taskItem.Metadata.Labels["execution_instance_id"])
+
+	sourceDumpTask, targetDumpTask, diffTask, err := p.getPipelineTasks(taskItem, &cfg)
+	if err != nil {
+		log.Errorf("failed to get pipeline tasks, err: %v", err)
+		return nil
+	}
+	if sourceDumpTask == nil || targetDumpTask == nil || diffTask == nil {
+		// ES might not synced yet
+		log.Warnf("task [%s] pipeline task(s) not found", taskItem.ID)
+		return nil
+	}
+
+	if migration_util.IsRunningState(sourceDumpTask.Status) || migration_util.IsRunningState(targetDumpTask.Status) || migration_util.IsRunningState(diffTask.Status) {
+		return nil
+	}
+	if sourceDumpTask.Status == task.StatusComplete && targetDumpTask.Status == task.StatusComplete {
+		sourceDocs := migration_util.GetMapIntValue(util.MapStr(sourceDumpTask.Metadata.Labels), "scrolled_docs")
+		targetDocs := migration_util.GetMapIntValue(util.MapStr(targetDumpTask.Metadata.Labels), "scrolled_docs")
+		if sourceDocs != targetDocs {
+			now := time.Now()
+			taskItem.CompletedTime = &now
+			taskItem.Status = task.StatusError
+			p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+				Success: false,
+			}, fmt.Sprintf("index comparison failed, source/target doc count unmatch: %d / %d", sourceDocs, targetDocs))
+			p.scheduler.DecrInstanceJobs(instanceID)
+			return nil
+		}
+		if diffTask.Status == task.StatusInit {
+			diffTask.Status = task.StatusReady
+			p.saveTaskAndWriteLog(diffTask, &task.TaskResult{
+				Success: true,
+			}, fmt.Sprintf("source/target dump completed, diff pipeline started"))
+			return nil
+		}
+		if diffTask.Status == task.StatusComplete {
+			m := util.MapStr(diffTask.Metadata.Labels)
+			var (
+				onlyInSource     = migration_util.GetMapIntValue(m, "only_in_source_count")
+				onlyInSourceKeys = migration_util.GetMapStringValue(m, "only_in_source_keys")
+				onlyInTarget     = migration_util.GetMapIntValue(m, "only_in_target_count")
+				onlyInTargetKeys = migration_util.GetMapStringValue(m, "only_in_target_keys")
+				diffBoth         = migration_util.GetMapIntValue(m, "diff_both_count")
+				diffBothKeys     = migration_util.GetMapStringValue(m, "diff_both_keys")
+			)
+			if onlyInSource > 0 || onlyInTarget > 0 || diffBoth > 0 {
+				now := time.Now()
+				taskItem.CompletedTime = &now
+				taskItem.Status = task.StatusError
+				p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+					Success: false,
+					Error:   "data unmatch",
+				}, fmt.Sprintf("index comparison failed, only in source: %d, only in target: %d, diff in both: %d (sample doc ids: [%s], [%s] [%s])", onlyInSource, onlyInTarget, diffBoth, onlyInSourceKeys, onlyInTargetKeys, diffBothKeys))
+				p.scheduler.DecrInstanceJobs(instanceID)
+				return nil
+			}
+		}
+	}
+	if sourceDumpTask.Status == task.StatusError || targetDumpTask.Status == task.StatusError || diffTask.Status == task.StatusError {
+		now := time.Now()
+		taskItem.CompletedTime = &now
+		taskItem.Status = task.StatusError
+		p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+			Success: false,
+			Error:   "pipeline task failed",
+		}, "index comparison failed")
+		p.scheduler.DecrInstanceJobs(instanceID)
+		return nil
+	}
+
+	now := time.Now()
+	taskItem.CompletedTime = &now
+	taskItem.Status = task.StatusComplete
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: true,
+	}, "index comparison completed")
+	p.scheduler.DecrInstanceJobs(instanceID)
+
+	return nil
+}
+
+func (p *processor) handlePendingStopSubTask(taskItem *task.Task) error {
+	err := migration_util.UpdatePendingChildTasksToPendingStop(taskItem, "pipeline")
+	if err != nil {
+		log.Errorf("failed to update sub task status, err: %v", err)
+		return nil
+	}
+
+	tasks, err := migration_util.GetPendingChildTasks(p.Elasticsearch, p.IndexName, taskItem.ID, "pipeline")
+	if err != nil {
+		log.Errorf("failed to get sub tasks, err: %v", err)
+		return nil
+	}
+
+	// all subtask stopped or error or complete
+	if len(tasks) == 0 {
+		taskItem.Status = task.StatusStopped
+		p.saveTaskAndWriteLog(taskItem, nil, fmt.Sprintf("index comparison task [%s] stopped", taskItem.ID))
+	}
+	return nil
+}
+
+func (p *processor) getPipelineTasks(taskItem *task.Task, cfg *migration_model.IndexComparisonTaskConfig) (sourceDumpTask *task.Task, targetDumpTask *task.Task, diffTask *task.Task, err error) {
+	ptasks, err := migration_util.GetChildTasks(p.Elasticsearch, p.IndexName, taskItem.ID, "pipeline", nil)
+	if err != nil {
+		log.Errorf("failed to get pipeline tasks, err: %v", err)
+		return
+	}
+	if len(ptasks) != 3 {
+		err = fmt.Errorf("invalid pipeline task count: %d", len(ptasks))
+		return
+	}
+	for i, ptask := range ptasks {
+		if ptask.Metadata.Labels["pipeline_id"] == "dump_hash" {
+			// TODO: we can't handle when compare the same cluster & same index
+			// catch it earlier when creating the task
+			if ptask.Metadata.Labels["cluster_id"] == cfg.Source.ClusterId && ptask.Metadata.Labels["index_name"] == cfg.Source.Indices {
+				sourceDumpTask = &ptasks[i]
+			} else {
+				targetDumpTask = &ptasks[i]
+			}
+		} else if ptask.Metadata.Labels["pipeline_id"] == "index_diff" {
+			diffTask = &ptasks[i]
+		}
+	}
+	return
+}
+
+// NOTE: only index_diff have an output queue, others are local files
+func (p *processor) cleanGatewayQueue(taskItem *task.Task) {
+	log.Debugf("cleaning gateway queue for task [%s]", taskItem.ID)
+
+	var err error
+	instance := model.Instance{}
+	instance.ID, _ = util.ExtractString(taskItem.Metadata.Labels["execution_instance_id"])
+	if instance.ID == "" {
+		log.Debugf("task [%s] not scheduled yet, skip cleaning queue", taskItem.ID)
+		return
+	}
+	_, err = orm.Get(&instance)
+	if err != nil {
+		log.Errorf("failed to get instance, err: %v", err)
+		return
+	}
+
+	selector := util.MapStr{
+		"labels": util.MapStr{
+			"comparison_task_id": taskItem.ID,
+		},
+	}
+	err = instance.DeleteQueueBySelector(selector)
+	if err != nil {
+		log.Errorf("failed to delete queue, err: %v", err)
+	}
+}
+
+func (p *processor) saveTaskAndWriteLog(taskItem *task.Task, taskResult *task.TaskResult, message string) {
+	esClient := elastic.GetClient(p.Elasticsearch)
+	_, err := esClient.Index(p.IndexName, "", taskItem.ID, taskItem, "")
+	if err != nil {
+		log.Errorf("failed to update task, err: %v", err)
+	}
+	if message != "" {
+		migration_util.WriteLog(taskItem, taskResult, message)
+	}
+}
--- a/plugin/migration/index_migration/index_migration.go
+++ b/plugin/migration/index_migration/index_migration.go
@ -93,10 +93,6 @@ func (p *processor) handleSplitSubTask(taskItem *task.Task) error {
 	if len(taskItem.ParentId) == 0 {
 		return fmt.Errorf("got wrong parent id of task [%v]", *taskItem)
 	}
-	queryDsl := cfg.Source.QueryDSL
-	scrollQueryDsl := util.MustToJSON(util.MapStr{
-		"query": queryDsl,
-	})
 	indexName := cfg.Source.Indices
 	scrollTask := &task.Task{
 		ParentId:    pids,
@ -140,9 +136,11 @@ func (p *processor) handleSplitSubTask(taskItem *task.Task) error {
 						},
 						"partition_size": 1,
 						"scroll_time":    cfg.Source.ScrollTime,
-						"query_dsl":      scrollQueryDsl,
-						"index_rename":   cfg.Source.IndexRename,
-						"type_rename":    cfg.Source.TypeRename,
+						"query_dsl": util.MustToJSON(util.MapStr{
+							"query": cfg.Source.QueryDSL,
+						}),
+						"index_rename": cfg.Source.IndexRename,
+						"type_rename":  cfg.Source.TypeRename,
 					},
 				},
 			},
@ -279,7 +277,6 @@ func (p *processor) handleScheduleSubTask(taskItem *task.Task) error {
 			if err == migration_model.ErrHitMax {
 				log.Debug("hit max tasks per instance, skip dispatch")
 				return nil
-
 			}
 			return fmt.Errorf("get preference intance error: %w", err)
 		}
@ -492,11 +489,15 @@ func (p *processor) getExecutionConfigFromMajorTask(taskItem *task.Task) (config
 }

 func (p *processor) getScrollBulkPipelineTasks(taskItem *task.Task) (scrollTask *task.Task, bulkTask *task.Task, err error) {
-	ptasks, err := p.getPipelineTasks(taskItem.ID)
+	ptasks, err := migration_util.GetChildTasks(p.Elasticsearch, p.IndexName, taskItem.ID, "pipeline", nil)
 	if err != nil {
 		log.Errorf("failed to get pipeline tasks, err: %v", err)
 		return
 	}
+	if len(ptasks) != 2 {
+		err = fmt.Errorf("invalid pipeline task count: %d", len(ptasks))
+		return
+	}
 	for i, ptask := range ptasks {
 		if ptask.Metadata.Labels["pipeline_id"] == "bulk_indexing" {
 			bulkTask = &ptasks[i]
@ -507,33 +508,6 @@ func (p *processor) getScrollBulkPipelineTasks(taskItem *task.Task) (scrollTask
 	return
 }

-func (p *processor) getPipelineTasks(subTaskID string) ([]task.Task, error) {
-	queryDsl := util.MapStr{
-		"size": 2,
-		"query": util.MapStr{
-			"bool": util.MapStr{
-				"must": []util.MapStr{
-					{
-						"term": util.MapStr{
-							"parent_id": util.MapStr{
-								"value": subTaskID,
-							},
-						},
-					},
-					{
-						"term": util.MapStr{
-							"metadata.type": util.MapStr{
-								"value": "pipeline",
-							},
-						},
-					},
-				},
-			},
-		},
-	}
-	return migration_util.GetTasks(p.Elasticsearch, p.IndexName, queryDsl)
-}
-
 func (p *processor) cleanGatewayQueue(taskItem *task.Task) {
 	log.Debugf("cleaning gateway queue for task [%s]", taskItem.ID)

--- a/plugin/migration/model/comparison.go
+++ b/plugin/migration/model/comparison.go
@ -0,0 +1,55 @@
+package model
+
+import "infini.sh/framework/core/util"
+
+type ClusterComparisonTaskConfig struct {
+	Cluster struct {
+		Source ClusterInfo `json:"source"`
+		Target ClusterInfo `json:"target"`
+	} `json:"cluster"`
+	Indices  []ClusterComparisonIndexConfig `json:"indices"`
+	Settings struct {
+		Dump      DumpHashConfig  `json:"dump"`
+		Diff      IndexDiffConfig `json:"diff"`
+		Execution ExecutionConfig `json:"execution"`
+	} `json:"settings"`
+	Creator struct {
+		Name string `json:"name"`
+		Id   string `json:"id"`
+	} `json:"creator"`
+}
+
+type ClusterComparisonIndexConfig struct {
+	Source    IndexInfo       `json:"source"`
+	Target    IndexInfo       `json:"target"`
+	RawFilter interface{}     `json:"raw_filter"`
+	Partition *IndexPartition `json:"partition,omitempty"`
+
+	// only used in API
+	Percent         float64 `json:"percent,omitempty"`
+	ErrorPartitions int     `json:"error_partitions,omitempty"`
+}
+
+type IndexComparisonTaskConfig struct {
+	Source    IndexComparisonDumpConfig `json:"source"`
+	Target    IndexComparisonDumpConfig `json:"target"`
+	Diff      IndexComparisonDiffConfig `json:"diff"`
+	Execution ExecutionConfig           `json:"execution"`
+}
+
+type IndexComparisonDumpConfig struct {
+	ClusterId string `json:"cluster_id"`
+	Indices   string `json:"indices"`
+
+	SliceSize     int         `json:"slice_size"`
+	BatchSize     int         `json:"batch_size"`
+	PartitionSize int         `json:"partition_size"`
+	ScrollTime    string      `json:"scroll_time"`
+	QueryString   string      `json:"query_string,omitempty"`
+	QueryDSL      util.MapStr `json:"query_dsl,omitempty"`
+
+	DocCount int64 `json:"doc_count"`
+}
+
+type IndexComparisonDiffConfig struct {
+}
--- a/plugin/migration/model/model.go
+++ b/plugin/migration/model/model.go
@ -15,15 +15,9 @@ type ClusterMigrationTaskConfig struct {
 	} `json:"cluster"`
 	Indices  []ClusterMigrationIndexConfig `json:"indices"`
 	Settings struct {
-		ParallelIndices      int `json:"parallel_indices"`
-		ParallelTaskPerIndex int `json:"parallel_task_per_index"`
-		Scroll               struct {
-			SliceSize int    `json:"slice_size"`
-			Docs      int    `json:"docs"`
-			Timeout   string `json:"timeout"`
-		} `json:"scroll"`
-		Bulk      ClusterMigrationBulkConfig `json:"bulk"`
-		Execution ExecutionConfig            `json:"execution"`
+		Scroll    EsScrollConfig     `json:"scroll"`
+		Bulk      BulkIndexingConfig `json:"bulk"`
+		Execution ExecutionConfig    `json:"execution"`
 	} `json:"settings"`
 	Creator struct {
 		Name string `json:"name"`
@ -31,24 +25,17 @@ type ClusterMigrationTaskConfig struct {
 	} `json:"creator"`
 }

-type ClusterMigrationBulkConfig struct {
-	Docs                 int  `json:"docs"`
-	StoreSizeInMB        int  `json:"store_size_in_mb"`
-	MaxWorkerSize        int  `json:"max_worker_size"`
-	IdleTimeoutInSeconds int  `json:"idle_timeout_in_seconds"`
-	SliceSize            int  `json:"slice_size"`
-	Compress             bool `json:"compress"`
-}
-
 type ClusterMigrationIndexConfig struct {
-	Source          IndexInfo              `json:"source"`
-	Target          IndexInfo              `json:"target"`
-	RawFilter       interface{}            `json:"raw_filter"`
-	IndexRename     map[string]interface{} `json:"index_rename"`
-	TypeRename      map[string]interface{} `json:"type_rename"`
-	Partition       *IndexPartition        `json:"partition,omitempty"`
-	Percent         float64                `json:"percent,omitempty"`
-	ErrorPartitions int                    `json:"error_partitions,omitempty"`
+	Source      IndexInfo              `json:"source"`
+	Target      IndexInfo              `json:"target"`
+	RawFilter   interface{}            `json:"raw_filter"`
+	IndexRename map[string]interface{} `json:"index_rename"`
+	TypeRename  map[string]interface{} `json:"type_rename"`
+	Partition   *IndexPartition        `json:"partition,omitempty"`
+
+	// only used in API
+	Percent         float64 `json:"percent,omitempty"`
+	ErrorPartitions int     `json:"error_partitions,omitempty"`
 }

 type MajorTaskState struct {
--- a/plugin/migration/model/pipeline.go
+++ b/plugin/migration/model/pipeline.go
@ -2,6 +2,35 @@ package model

 import "infini.sh/framework/core/util"

+// tunable `es_scroll` configurations
+type EsScrollConfig struct {
+	SliceSize int    `json:"slice_size"`
+	Docs      int    `json:"docs"`
+	Timeout   string `json:"timeout"`
+}
+
+// tunable `dump_hash` configurations
+type DumpHashConfig struct {
+	SliceSize     int    `json:"slice_size"`
+	PartitionSize int    `json:"partition_size"`
+	Docs          int    `json:"docs"`
+	Timeout       string `json:"timeout"`
+}
+
+// tunable `index_diff` configurations
+type IndexDiffConfig struct {
+}
+
+// tunable `bulk_indexing` configurations
+type BulkIndexingConfig struct {
+	Docs                 int  `json:"docs"`
+	StoreSizeInMB        int  `json:"store_size_in_mb"`
+	MaxWorkerSize        int  `json:"max_worker_size"`
+	IdleTimeoutInSeconds int  `json:"idle_timeout_in_seconds"`
+	SliceSize            int  `json:"slice_size"`
+	Compress             bool `json:"compress"`
+}
+
 type PipelineTaskLoggingConfig struct {
 	Enabled bool `json:"enabled"`
 }
--- a/plugin/migration/pipeline.go
+++ b/plugin/migration/pipeline.go
@ -11,7 +11,9 @@ import (

 	log "github.com/cihub/seelog"

+	"infini.sh/console/plugin/migration/cluster_comparison"
 	"infini.sh/console/plugin/migration/cluster_migration"
+	"infini.sh/console/plugin/migration/index_comparison"
 	"infini.sh/console/plugin/migration/index_migration"
 	migration_model "infini.sh/console/plugin/migration/model"
 	"infini.sh/console/plugin/migration/pipeline_task"
@ -32,10 +34,12 @@ type DispatcherProcessor struct {
 	id     string
 	config *DispatcherConfig

-	scheduler                     migration_model.Scheduler
-	pipelineTaskProcessor         migration_model.Processor
-	clusterMigrationTaskProcessor migration_model.Processor
-	indexMigrationTaskProcessor   migration_model.Processor
+	scheduler                      migration_model.Scheduler
+	pipelineTaskProcessor          migration_model.Processor
+	clusterMigrationTaskProcessor  migration_model.Processor
+	indexMigrationTaskProcessor    migration_model.Processor
+	clusterComparisonTaskProcessor migration_model.Processor
+	indexComparisonTaskProcessor   migration_model.Processor
 }

 type DispatcherConfig struct {
@ -95,6 +99,8 @@ func newMigrationDispatcherProcessor(c *config.Config) (pipeline.Processor, erro
 	processor.pipelineTaskProcessor = pipeline_task.NewProcessor(cfg.Elasticsearch, cfg.IndexName, cfg.LogIndexName)
 	processor.indexMigrationTaskProcessor = index_migration.NewProcessor(cfg.Elasticsearch, cfg.IndexName, processor.scheduler)
 	processor.clusterMigrationTaskProcessor = cluster_migration.NewProcessor(cfg.Elasticsearch, cfg.IndexName, processor.scheduler)
+	processor.indexComparisonTaskProcessor = index_comparison.NewProcessor(cfg.Elasticsearch, cfg.IndexName, processor.scheduler)
+	processor.clusterComparisonTaskProcessor = cluster_comparison.NewProcessor(cfg.Elasticsearch, cfg.IndexName, processor.scheduler)

 	return &processor, nil
 }
@ -106,17 +112,21 @@ func (p *DispatcherProcessor) Name() string {
 func (p *DispatcherProcessor) Process(ctx *pipeline.Context) error {
 	// handle pipeline task
 	p.handleTasks(ctx, "pipeline", []string{task2.StatusReady, task2.StatusRunning, task2.StatusPendingStop}, p.pipelineTaskProcessor.Process)
-	// mark index_migrations as pending_stop
+
+	// handle comparison tasks
+	p.handleTasks(ctx, "cluster_comparison", []string{task2.StatusPendingStop}, p.clusterComparisonTaskProcessor.Process)
+	p.handleTasks(ctx, "index_comparison", []string{task2.StatusPendingStop}, p.indexComparisonTaskProcessor.Process)
+	p.handleTasks(ctx, "index_comparison", []string{task2.StatusRunning}, p.indexComparisonTaskProcessor.Process)
+	p.handleTasks(ctx, "index_comparison", []string{task2.StatusReady}, p.indexComparisonTaskProcessor.Process)
+	p.handleTasks(ctx, "cluster_comparison", []string{task2.StatusRunning}, p.clusterComparisonTaskProcessor.Process)
+	p.handleTasks(ctx, "cluster_comparison", []string{task2.StatusReady}, p.clusterComparisonTaskProcessor.Process)
+
+	// handle migration tasks
 	p.handleTasks(ctx, "cluster_migration", []string{task2.StatusPendingStop}, p.clusterMigrationTaskProcessor.Process)
-	// mark pipeline tasks as pending_stop
 	p.handleTasks(ctx, "index_migration", []string{task2.StatusPendingStop}, p.indexMigrationTaskProcessor.Process)
-	// check pipeline tasks status
 	p.handleTasks(ctx, "index_migration", []string{task2.StatusRunning}, p.indexMigrationTaskProcessor.Process)
-	// split & schedule pipline tasks
 	p.handleTasks(ctx, "index_migration", []string{task2.StatusReady}, p.indexMigrationTaskProcessor.Process)
-	// check index_migration tasks status
 	p.handleTasks(ctx, "cluster_migration", []string{task2.StatusRunning}, p.clusterMigrationTaskProcessor.Process)
-	// split & schedule index_migration tasks
 	p.handleTasks(ctx, "cluster_migration", []string{task2.StatusReady}, p.clusterMigrationTaskProcessor.Process)
 	return nil
 }
--- a/plugin/migration/pipeline_task/dump_hash.go
+++ b/plugin/migration/pipeline_task/dump_hash.go
@ -0,0 +1,76 @@
+package pipeline_task
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	log "github.com/cihub/seelog"
+	migration_util "infini.sh/console/plugin/migration/util"
+	"infini.sh/framework/core/task"
+)
+
+func (p *processor) handleRunningDumpHashPipelineTask(taskItem *task.Task) error {
+	scrolledDocs, totalHits, scrolled, err := p.getDumpHashTaskState(taskItem)
+
+	if !scrolled {
+		return nil
+	}
+
+	var errMsg string
+	if err != nil {
+		errMsg = err.Error()
+	}
+	if errMsg == "" {
+		if scrolledDocs < totalHits {
+			errMsg = fmt.Sprintf("scrolled finished but docs count unmatch: %d / %d", scrolledDocs, totalHits)
+		}
+	}
+
+	now := time.Now()
+	taskItem.CompletedTime = &now
+	taskItem.Metadata.Labels["scrolled_docs"] = scrolledDocs
+	if errMsg != "" {
+		taskItem.Status = task.StatusError
+	} else {
+		taskItem.Status = task.StatusComplete
+	}
+
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: errMsg == "",
+		Error:   errMsg,
+	}, fmt.Sprintf("[dump_hash] pipeline task [%s] completed", taskItem.ID))
+	p.cleanGatewayPipeline(taskItem)
+	return nil
+}
+
+func (p *processor) getDumpHashTaskState(taskItem *task.Task) (scrolledDocs int64, totalHits int64, scrolled bool, err error) {
+	hits, err := p.getPipelineLogs(taskItem, []string{"FINISHED", "FAILED"}, taskItem.Updated.UnixMilli())
+	if err != nil {
+		log.Errorf("failed to get pipeline logs for task [%s], err: %v", taskItem.ID, err)
+		err = nil
+		return
+	}
+	if len(hits) == 0 {
+		log.Debugf("scroll task [%s] not finished yet since last start", taskItem.ID)
+		return
+	}
+	for _, m := range hits {
+		scrolled = true
+
+		errStr := migration_util.GetMapStringValue(m, "payload.pipeline.logging.result.error")
+		if errStr != "" {
+			err = errors.New(errStr)
+			return
+		}
+
+		var (
+			scroll = migration_util.GetMapIntValue(m, "payload.pipeline.logging.context.dump_hash.scrolled_docs")
+			total  = migration_util.GetMapIntValue(m, "payload.pipeline.logging.context.dump_hash.total_hits")
+		)
+
+		scrolledDocs += scroll
+		totalHits += total
+	}
+	return
+}
--- a/plugin/migration/pipeline_task/index_diff.go
+++ b/plugin/migration/pipeline_task/index_diff.go
@ -0,0 +1,93 @@
+package pipeline_task
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	log "github.com/cihub/seelog"
+	migration_util "infini.sh/console/plugin/migration/util"
+	"infini.sh/framework/core/task"
+)
+
+func (p *processor) handleRunningIndexDiffPipelineTask(taskItem *task.Task) error {
+
+	diffed, onlyInSourceCount, totalOnlyInSourceDocs, onlyInTargetCount, totalOnlyInTargetDocs, diffBothCount, totalDiffBothDocs, errs := p.getIndexDiffTaskState(taskItem)
+	if !diffed {
+		return nil
+	}
+
+	var errMsg string
+	if len(errs) > 0 {
+		errMsg = fmt.Sprintf("index diff finished with error(s): %v", errs)
+	}
+
+	now := time.Now()
+	taskItem.CompletedTime = &now
+	// NOTE: only_in_source/only_in_target is likely useless because we'll skip diff if doc count unmatch
+	taskItem.Metadata.Labels["only_in_source_count"] = onlyInSourceCount
+	taskItem.Metadata.Labels["only_in_source_keys"] = strings.Join(totalOnlyInSourceDocs, ",")
+	taskItem.Metadata.Labels["only_in_target_count"] = onlyInTargetCount
+	taskItem.Metadata.Labels["only_in_target_keys"] = strings.Join(totalOnlyInTargetDocs, ",")
+	taskItem.Metadata.Labels["diff_both_count"] = diffBothCount
+	taskItem.Metadata.Labels["diff_both_keys"] = strings.Join(totalDiffBothDocs, ",")
+
+	if errMsg != "" {
+		taskItem.Status = task.StatusError
+	} else {
+		taskItem.Status = task.StatusComplete
+	}
+
+	p.saveTaskAndWriteLog(taskItem, &task.TaskResult{
+		Success: errMsg == "",
+		Error:   errMsg,
+	}, fmt.Sprintf("[index_diff] pipeline task [%s] finished with status [%s]", taskItem.ID, taskItem.Status))
+	p.cleanGatewayPipeline(taskItem)
+	return nil
+}
+
+func (p *processor) getIndexDiffTaskState(taskItem *task.Task) (diffed bool, onlyInSourceCount int64, totalOnlyInSourceDocs []string, onlyInTargetCount int64, totalOnlyInTargetDocs []string, diffBothCount int64, totalDiffBothDocs []string, errs []string) {
+	newHits, err := p.getPipelineLogs(taskItem, []string{"FINISHED", "FAILED"}, taskItem.Updated.UnixMilli())
+	if err != nil {
+		log.Errorf("failed to get latest pipeline logs for task [%s], err: %v", taskItem.ID, err)
+		return
+	}
+	if len(newHits) == 0 {
+		log.Debugf("bulk task [%s] not finished yet since last start", taskItem.ID)
+		return
+	}
+
+	hits, err := p.getPipelineLogs(taskItem, []string{"FINISHED", "FAILED"}, 0)
+	if err != nil {
+		log.Errorf("failed to get all pipeline logs for task [%s], err: %v", taskItem.ID, err)
+		return
+	}
+
+	for _, m := range hits {
+		diffed = true
+
+		errStr := migration_util.GetMapStringValue(m, "payload.pipeline.logging.result.error")
+		if errStr != "" {
+			errs = append(errs, errStr)
+		}
+
+		var (
+			onlyInSource = migration_util.GetMapIntValue(m, "payload.pipeline.logging.context.index_diff.only_in_source.count")
+			onlyInTarget = migration_util.GetMapIntValue(m, "payload.pipeline.logging.context.index_diff.only_in_target.count")
+			diffBoth     = migration_util.GetMapIntValue(m, "payload.pipeline.logging.context.index_diff.diff_both.count")
+		)
+		onlyInSourceCount += onlyInSource
+		onlyInTargetCount += onlyInTarget
+		diffBothCount += diffBoth
+
+		var (
+			onlyInSourceDocs = migration_util.GetMapStringSliceValue(m, "payload.pipeline.logging.context.index_diff.only_in_source.keys")
+			onlyInTargetDocs = migration_util.GetMapStringSliceValue(m, "payload.pipeline.logging.context.index_diff.only_in_target.keys")
+			diffBothDocs     = migration_util.GetMapStringSliceValue(m, "payload.pipeline.logging.context.index_diff.diff_both.keys")
+		)
+		totalOnlyInSourceDocs = append(totalOnlyInSourceDocs, onlyInSourceDocs...)
+		totalOnlyInTargetDocs = append(totalOnlyInTargetDocs, onlyInTargetDocs...)
+		totalDiffBothDocs = append(totalDiffBothDocs, diffBothDocs...)
+	}
+	return
+}
--- a/plugin/migration/pipeline_task/pipeline_task.go
+++ b/plugin/migration/pipeline_task/pipeline_task.go
@ -25,6 +25,11 @@ type processor struct {
 	LogIndexName  string
 }

+var (
+	// task types with pipline as children
+	parentTaskTypes = []string{"index_migration", "index_comparison"}
+)
+
 func NewProcessor(elasticsearch, indexName, logIndexName string) migration_model.Processor {
 	return &processor{
 		Elasticsearch: elasticsearch,
@ -52,6 +57,8 @@ func (p *processor) handleReadyPipelineTask(taskItem *task.Task) error {
 	switch taskItem.Metadata.Labels["pipeline_id"] {
 	case "es_scroll":
 	case "bulk_indexing":
+	case "dump_hash":
+	case "index_diff":
 	default:
 		return fmt.Errorf("task [%s] has unknown pipeline_id [%s]", taskItem.ID, taskItem.Metadata.Labels["pipeline_id"])
 	}
@ -108,6 +115,10 @@ func (p *processor) handleRunningPipelineTask(taskItem *task.Task) error {
 		return p.handleRunningEsScrollPipelineTask(taskItem)
 	case "bulk_indexing":
 		return p.handleRunningBulkIndexingPipelineTask(taskItem)
+	case "dump_hash":
+		return p.handleRunningDumpHashPipelineTask(taskItem)
+	case "index_diff":
+		return p.handleRunningIndexDiffPipelineTask(taskItem)
 	default:
 		return fmt.Errorf("task [%s] has unknown pipeline_id [%s]", taskItem.ID, taskItem.Metadata.Labels["pipeline_id"])
 	}
@ -158,7 +169,6 @@ func (p *processor) handleRunningBulkIndexingPipelineTask(taskItem *task.Task) e
 	if len(errs) > 0 {
 		errMsg = fmt.Sprintf("bulk finished with error(s): %v", errs)
 	}
-	// TODO: handle multiple run bulk_indexing pipeline tasks and total_docs from index_migration
 	now := time.Now()
 	taskItem.CompletedTime = &now
 	taskItem.Metadata.Labels["index_docs"] = indexDocs
@ -239,7 +249,7 @@ func (p *processor) cleanGatewayPipeline(taskItem *task.Task) (instance model.In
 }

 func (p *processor) getPipelineExecutionInstance(taskItem *task.Task) (instance model.Instance, err error) {
-	parentTask, err := p.getParentTask(taskItem, "index_migration")
+	parentTask, err := p.getParentTask(taskItem)
 	if err != nil {
 		return
 	}
@ -254,7 +264,7 @@ func (p *processor) getPipelineExecutionInstance(taskItem *task.Task) (instance
 	return
 }

-func (p *processor) getParentTask(taskItem *task.Task, taskType string) (*task.Task, error) {
+func (p *processor) getParentTask(taskItem *task.Task) (*task.Task, error) {
 	queryDsl := util.MapStr{
 		"size": 1,
 		"query": util.MapStr{
@ -266,8 +276,8 @@ func (p *processor) getParentTask(taskItem *task.Task, taskType string) (*task.T
 						},
 					},
 					{
-						"term": util.MapStr{
-							"metadata.type": taskType,
+						"terms": util.MapStr{
+							"metadata.type": parentTaskTypes,
 						},
 					},
 				},
@ -471,7 +481,7 @@ func (p *processor) fillDynamicESConfig(taskItem *task.Task, pipelineTaskConfig
 				return errors.New("invalid processor config")
 			}
 			processorConfig := util.MapStr(v)
-			if k == "bulk_indexing" || k == "es_scroll" {
+			if k == "bulk_indexing" || k == "es_scroll" || k == "dump_hash" {
 				elasticsearchID := migration_util.GetMapStringValue(processorConfig, "elasticsearch")
 				if elasticsearchID == "" {
 					return fmt.Errorf("invalid task config found for task [%s]", taskItem.ID)
--- a/plugin/migration/util/orm.go
+++ b/plugin/migration/util/orm.go
@ -11,35 +11,40 @@ import (
 )

 func GetPendingChildTasks(elasticsearch, indexName string, taskID string, taskType string) ([]task.Task, error) {
+	return GetChildTasks(elasticsearch, indexName, taskID, taskType, []string{task.StatusRunning, task.StatusPendingStop, task.StatusReady})
+}

-	//check whether all pipeline task is stopped or not, then update task status
-	q := util.MapStr{
-		"size": 200,
-		"query": util.MapStr{
-			"bool": util.MapStr{
-				"must": []util.MapStr{
-					{
-						"term": util.MapStr{
-							"parent_id": util.MapStr{
-								"value": taskID,
-							},
-						},
-					},
-					{
-						"term": util.MapStr{
-							"metadata.type": taskType,
-						},
-					},
-					{
-						"terms": util.MapStr{
-							"status": []string{task.StatusRunning, task.StatusPendingStop, task.StatusReady},
-						},
-					},
+func GetChildTasks(elasticsearch, indexName string, taskID string, taskType string, status []string) ([]task.Task, error) {
+	musts := []util.MapStr{
+		{
+			"term": util.MapStr{
+				"parent_id": util.MapStr{
+					"value": taskID,
 				},
 			},
 		},
+		{
+			"term": util.MapStr{
+				"metadata.type": taskType,
+			},
+		},
 	}
-	return GetTasks(elasticsearch, indexName, q)
+	if len(status) > 0 {
+		musts = append(musts, util.MapStr{
+			"terms": util.MapStr{
+				"status": []string{task.StatusRunning, task.StatusPendingStop, task.StatusReady},
+			},
+		})
+	}
+	queryDsl := util.MapStr{
+		"size": 999,
+		"query": util.MapStr{
+			"bool": util.MapStr{
+				"must": musts,
+			},
+		},
+	}
+	return GetTasks(elasticsearch, indexName, queryDsl)
 }

 func GetTasks(elasticsearch, indexName string, query interface{}) ([]task.Task, error) {