Remove segment status

Signed-off-by: bigsheeper <yihao.dai@zilliz.com>
2020-10-24 10:45:57 +08:00 · 2020-10-24 10:45:57 +08:00 · 52932da551
parent e84b0180c9
commit 52932da551
32 changed files with 3467 additions and 744 deletions
--- a/docs/developer_guides/developer_guides.md
+++ b/docs/developer_guides/developer_guides.md
@ -0,0 +1,592 @@
+
+
+# Milvus Developer Guides
+
+                                                                                                                                   by Rentong Guo, Sep 15, 2020
+
+
+
+## 1. System Overview
+
+In this section, we sketch the system design of Milvus , including data model, data organization, architecture, and state synchronization. 
+
+
+
+#### 1.1 Data Model
+
+Milvus exposes the following set of data features to applications:
+
+* a data model based on schematized relational tables, in that rows must have primary-keys,
+
+* a query language specifies data definition, data manipulation, and data query, where data definition includes create, drop, and data manipulation includes insert, upsert, delete, and data query falls into three types, primary key search, approximate nearest neighbor search (ANNS), ANNS with predicates.
+
+The requests' execution order is strictly in accordance with their issue-time order. We take proxy's issue time as a requst's issue time. For a batch request, all its sub-requests share a same issue time. In cases there are multiple proxies, issue time from different proxies are regarded as coming from a central clock.
+
+Transaction is currently not supported by Milvus. Only batch requests such as batch insert/delete/query are supported. A batch insert/delete is guaranteed to become visible atomically.
+
+
+
+#### 1.2 Data Organization
+
+
+
+<img src="./figs/data_organization.pdf" width=550>
+
+In Milvus, 'collection' refers to the concept of table. A collection can be optionally divided into several 'partitions'. Both collection and partition are the basic execution scopes of queries. When use parition, users should clearly know how a collection should be partitioned. In most cases, parition leads to more flexible data management and more efficient quering. For a partitioned collection, queries can be executed both on the collection or a set of specified partitions.
+
+Each collection or parition contains a set of 'segment groups'. Segment group is the basic unit of data-to-node mapping. It's also the basic unit of replica. For instance, if a query node failed, its segment groups will be redistributed accross other nodes. If a query node is overloaded, part of its  segment groups will be migrated to underloaded ones. If a hot collection/partition is detected, its segment groups will be replicated to smooth the system load skewness.
+
+'Segment' is the finest unit of data organization. It is where the data and indexes are actually kept. Each segment contains a set of rows. In order to reduce the memory footprint during a query execution and to fully utilize SIMD, the physical data layout within segments is organized in a column-based manner. 
+
+
+
+#### 1.3 Architecture Overview
+
+
+
+<img src="./figs/system_framework.pdf" width=800>
+
+The main components, proxy, WAL, query node and write node can scale to multiple instances. These components scale seperately for better tradeoff between availability and cost.
+
+The WAL forms a hash ring. Requests (i.e. inserts and deletes) from clients will be repacked by proxy. Operations shared identical hash value (the hash value of primary key) will be routed to the same hash bucket. In addtion, some preprocessing work will be done by proxy, such as static validity checking, primary key assignment (if not given by user), timestamp assignment.
+
+The query/write nodes are linked to the hash ring, with each node covers some portion of the buckets. Once the hash function and bucket coverage are settled, the chain 'proxy -> WAL -> query/write node' will act as a producer-consumer pipeline. Logs in each bucket is a determined operation stream. Via performing the operation stream in order, the query nodes keep themselves up to date.
+
+The query nodes hold all the indexes in memory. Since building index is time-consuming, the query nodes will dump their index to disk (store engine) for fast failure recovery and cross node index copy.
+
+The write nodes are stateless. They simply transforms the newly arrived WALs to binlog format, then append the binlog to store enginey. 
+
+Note that not all the components are necessarily replicated. The system provides failure tolerance by maintaining multiple copies of WAL and binlog. When there is no in-memory index replica and there occurs a query node failure, other query nodes will take over its indexes by loading the dumped index files, or rebuilding them from binlog and WALs. The links from query nodes to the hash ring will also be adjusted such that the failure node's input WAL stream can be properly handled by its neighbors.
+
+
+
+#### 1.4 State Synchronization
+
+<img src="./figs/state_sync.pdf" width=800>
+
+Data in Milvus have three different forms, namely WAL, binlog, and index. As mentioned in the previous section, WAL can be viewed as a determined operation stream. Other two data forms keep themselves up to date by performing the operation stream in time order.
+
+Each of the WAL is attached with a timestamp, which is the time when the log is sent to the hash bucket. Binlog records, table rows, index cells will also keep that timestamp. In this way, different data forms can offer consistent snapshot for a given time T. For example, requests such as "fetch binlogs before T for point-in-time recovery", "get the row with primary key K at time T", "launch a similarity search at time T for vector V" perform on binlog, index respectively. Though different data forms these three requests are performed, they observe identical snapshot, namely all the state changes before T.
+
+For better throughput, Milvus allows asynchronous state synchronization between WAL and index/binlog/table. Whenever the data is not fresh enough to satisfiy a query, the query will be suspended until the data is up-to-date, or timeout will be returned.
+
+
+
+## 2. Schema
+
+#### 2.1 Collection Schema
+
+``` go
+type CollectionSchema struct {
+  Name string
+  Fields []FieldSchema
+}
+```
+
+#### 2.2 Field Schema
+
+``` go
+type FieldSchema struct {
+  Id uint64
+  Name string
+  Description string
+  DataType DataType 
+  TypeParams map[string]string
+  IndexParams map[string]string
+}
+```
+
+
+
+#### 2.3 Type Params
+
+#### 2.4 Index Params
+
+
+
+## 3. Request
+
+
+
+#### 3.1 Base Request
+
+``` go
+type BaseRequest interface {
+  Type() ReqType
+  PreExecute() Status
+  Execute() Status
+  PostExecute() Status
+  WaitToFinish() Status
+}
+```
+
+
+
+#### 3.2 Definition Requests
+
+###### 3.2.1 Collection
+
+* CreateCollection
+* DropCollection
+* HasCollection
+* DescribeCollection
+* ShowCollections
+
+###### 3.2.2 Partition
+
+* CreatePartition
+* DropPartition
+* HasPartition
+* DescribePartition
+* ShowPartitions
+
+###### 3.2.3 Index
+
+* CreateIndex
+* DropIndex
+* DescribeIndex
+
+###### 3.2.4 Definition Request & Task
+
+```go
+type DDRequest struct {
+  CollectionName string
+  PartitionName string
+  SegmentId uint64
+  ChannelId uint64
+  
+  PrimaryKeys []uint64
+  RowData []*RowDataBlob
+  
+  reqType ReqType
+  ts Timestamp
+}
+
+type DDTask struct {
+  DDRequest
+}
+
+// TsMsg interfaces
+func (req *DDTask) Ts() Timestamp
+func (req *DDTask) SetTs(ts Timestamp)
+
+// BaseRequest interfaces
+func (req *DDTask) Type() ReqType
+func (req *DDTask) PreExecute() Status
+func (req *DDTask) Execute() Status
+func (req *DDTask) PostExecute() Status
+func (req *DDTask) WaitToFinish() Status
+```
+
+
+
+#### 3.3 Manipulation Requsts
+
+###### 3.3.1 Insert
+
+* Insert
+
+###### 3.3.2 Delete
+
+* DeleteByID
+
+###### 3.3.3 Manipulation Requst
+
+```go
+type DMRequest struct {
+  CollectionName string
+  PartitionTag string
+  SegmentId uint64
+  ChannelId uint64
+  
+  PrimaryKeys []uint64
+  RowData []*RowDataBlob
+  
+  reqType ReqType
+  ts Timestamp
+}
+
+type DMTask struct {
+  DMRequest
+}
+
+// TsMsg interfaces
+func (req *DMTask) Ts() Timestamp
+func (req *DMTask) SetTs(ts Timestamp)
+
+// BaseRequest interfaces
+func (req *DMTask) Type() ReqType
+func (req *DMTask) PreExecute() Status
+func (req *DMTask) Execute() Status
+func (req *DMTask) PostExecute() Status
+func (req *DMTask) WaitToFinish() Status
+```
+
+
+
+#### 3.5 Query
+
+
+
+##  4. Time
+
+
+
+#### 4.1 Timestamp
+
+Before we discuss timestamp, let's take a brief review of Hybrid Logical Clock (HLC). HLC uses 64bits timestamps which are composed of a 46-bits physical component (thought of as and always close to local wall time) and a 18-bits logical component (used to distinguish between events with the same physical component).
+
+<img src="./figs/hlc.pdf" width=450>
+
+HLC's logical part is advanced on each request. The phsical part can be increased in two cases: 
+
+A. when the local wall time is greater than HLC's physical part,
+
+B. or the logical part overflows.
+
+In either cases, the physical part will be updated, and the logical part will be set to 0.
+
+Keep the physical part close to local wall time may face non-monotonic problems such as updates to POSIX time that could turn time backward. HLC avoids such problems, since if 'local wall time < HLC's physical part' holds, only case B is satisfied, thus montonicity is guaranteed.
+
+Milvus does not support transaction, but it should gurantee the deterministic execution of the multi-way WAL. The timestamp attached to each request should
+
+- have its physical part close to wall time (has an acceptable bounded error, a.k.a. uncertainty interval in transaction senarios),
+- and be globally unique.
+
+HLC leverages on physical clocks at nodes that are synchronized using the NTP. NTP usually maintain time to within tens of milliseconds over local networks in datacenter. Asymmetric routes and network congestion occasionally cause errors of hundreds of milliseconds. Both the normal time error and the spike are acceptable for Milvus use cases. 
+
+The interface of Timestamp is as follows.
+
+```
+type timestamp struct {
+  physical uint64 // 18-63 bits
+  logical uint64  // 0-17 bits
+}
+
+type Timestamp uint64
+```
+
+
+
+#### 4.2 Timestamp Oracle
+
+```
+type timestampOracle struct {
+  client *etcd.Client // client of a reliable meta service, i.e. etcd client
+  rootPath string // this timestampOracle's working root path on the reliable kv service
+  saveInterval uint64
+  lastSavedTime uint64
+  tso Timestamp // monotonically increasing timestamp
+}
+
+func (tso *timestampOracle) GetTimestamp(count uint32) ([]Timestamp, Status)
+
+func (tso *timestampOracle) saveTimestamp() Status
+func (tso *timestampOracle) loadTimestamp() Status
+```
+
+
+
+#### 4.3 Batch Allocation of Timestamps
+
+
+
+#### 4.4 Expiration of Timestamps
+
+
+
+#### 4.5 T_safe
+
+
+
+
+
+## 5. Basic Components
+
+#### 5.1 Watchdog
+
+``` go
+type ActiveComponent interface {
+  Id() string
+  Status() Status
+  Clean() Status
+  Restart() Status
+}
+
+type ComponentHeartbeat interface {
+  Id() string
+  Status() Status
+  Serialize() string
+}
+
+type Watchdog struct {
+  targets [] *ActiveComponent
+  heartbeats ComponentHeartbeat chan
+}
+
+// register ActiveComponent
+func (dog *Watchdog) Register(target *ActiveComponent)
+
+// called by ActiveComponents
+func (dog *Watchdog) PutHeartbeat(heartbeat *ComponentHeartbeat)
+
+// dump heatbeats as log stream
+func (dog *Watchdog) dumpHeartbeat(heartbeat *ComponentHeartbeat)
+```
+
+
+
+#### 5.2 Global Parameter Table
+
+``` go
+type GlobalParamsTable struct {
+  params memoryKV
+}
+
+func (gparams *GlobalParamsTable) Save(key, value string) Status
+func (gparams *GlobalParamsTable) Load(key string) (string, Status)
+func (gparams *GlobalParamsTable) LoadRange(key, endKey string, limit int) ([]string, []string, Status)
+func (gparams *GlobalParamsTable) Remove(key string) Status
+```
+
+
+
+
+
+## 6. Proxy
+
+#### 6.1 Overview
+
+#### 6.2 Request Scheduler
+
+``` go
+type requestScheduler struct {
+  definitions requestQueue
+  manipulations requestQueue
+  queries requestQueue
+}
+
+func (rs *requestScheduler) ExecuteRequest(req *Request) Status
+
+func (rs *requestScheduler) staticValidityCheck(req *Request) Status
+func (rs *requestScheduler) setTimestamp(req *Request)
+func (rs *requestScheduler) setPrimaryKey(req *Request)
+func (rs *requestScheduler) setSegmentId(req *Request)
+func (rs *requestScheduler) setProxyId(req *Request)
+
+// @param selection
+// bit_0 = 1: select definition queue
+// bit_1 = 1: select manipulation queue
+// bit_2 = 1: select query queue
+// example: if mode = 3, then both definition and manipulation queues are selected
+func (rs *requestScheduler) AreRequestsDelivered(ts Timestamp, selection uint32) bool
+
+// ActiveComponent interfaces
+func (rs *requestScheduler) Id() String
+func (rs *requestScheduler) Status() Status
+func (rs *requestScheduler) Clean() Status
+func (rs *requestScheduler) Restart() Status
+func (rs *requestScheduler) heartbeat()
+
+// protobuf
+message ReqSchedulerHeartbeat {
+  string id
+  uint64 definition_queue_length
+  uint64 manipulation_queue_length
+  uint64 query_queue_length
+  uint64 num_delivered_definitions
+  uint64 num_delivered_manipulations
+  uint64 num_delivered_queries
+}
+```
+
+
+
+#### 6.3 Time Tick
+
+``` go
+type timeTick struct {
+  lastTick Timestamp
+  currentTick Timestamp
+}
+
+func (tt *timeTick) tick() Status
+
+// ActiveComponent interfaces
+func (tt *timeTick) ID() String
+func (tt *timeTick) Status() Status
+func (tt *timeTick) Clean() Status
+func (tt *timeTick) Restart() Status
+func (tt *timeTick) heartbeat()
+
+// protobuf
+message TimeTickHeartbeat {
+  string id
+  uint64 last_tick
+}
+```
+
+
+
+## 7. Message Stream
+
+#### 7.1 Overview
+
+
+
+#### 7.2 Message Stream
+
+``` go
+type TsMsg interface {
+  SetTs(ts Timestamp)
+  Ts() Timestamp
+}
+
+type TsMsgMarshaler interface {
+  Marshal(input *TsMsg) ([]byte, Status)
+  Unmarshal(input []byte) (*TsMsg, Status)
+}
+
+type MsgPack struct {
+  BeginTs Timestamp
+  EndTs Timestamp
+  Msgs []*TsMsg
+}
+
+type MsgStream interface {
+  SetMsgMarshaler(marshal *TsMsgMarshaler, unmarshal *TsMsgMarshaler)
+  Produce(*MsgPack) Status
+  Consume() *MsgPack // message can be consumed exactly once
+}
+
+type PulsarMsgStream struct {
+  client *pulsar.Client
+  produceChannels []string
+  consumeChannels []string
+  
+  msgMarshaler *TsMsgMarshaler
+  msgUnmarshaler *TsMsgMarshaler
+}
+
+func (ms *PulsarMsgStream) SetMsgMarshaler(marshal *TsMsgMarshaler, unmarshal *TsMsgMarshaler)
+func (ms *PulsarMsgStream) Produce(*MsgPack) Status
+func (ms *PulsarMsgStream) Consume() *MsgPack //return messages in one time tick
+
+type PulsarTtMsgStream struct {
+  client *pulsar.Client
+  produceChannels []string
+  consumeChannels []string
+  
+  msgMarshaler *TsMsgMarshaler
+  msgUnmarshaler *TsMsgMarshaler
+  inputBuf []*TsMsg
+  unsolvedBuf []*TsMsg
+  msgPacks []*MsgPack
+}
+
+func (ms *PulsarTtMsgStream) SetMsgMarshaler(marshal *TsMsgMarshaler, unmarshal *TsMsgMarshaler)
+func (ms *PulsarTtMsgStream) Produce(*MsgPack) Status
+func (ms *PulsarTtMsgStream) Consume() *MsgPack //return messages in one time tick
+```
+
+
+
+## 8. Query Node
+
+
+
+#### 8.1 Collection and Segment Meta
+
+###### 8.1.1 Collection
+
+``` go
+type Collection struct {
+  Name string
+  Id uint64
+  Fields map[string]FieldMeta
+  SegmentsId []uint64
+  
+  cCollectionSchema C.CCollectionSchema
+}
+```
+
+
+
+###### 8.1.2 Field Meta
+
+```go
+type FieldMeta struct {
+  Name string
+  Id uint64
+  IsPrimaryKey bool
+  TypeParams map[string]string
+  IndexParams map[string]string
+}
+```
+
+
+
+###### 8.1.3 Segment
+
+``` go
+type Segment struct {
+  Id uint64
+  ParitionName string
+  CollectionId uint64
+  OpenTime Timestamp
+  CloseTime Timestamp
+  NumRows uint64
+  
+  cSegment C.CSegmentBase
+}
+```
+
+
+
+#### 8.2 Message Streams
+
+```go
+type ManipulationReqUnmarshaler struct {}
+
+// implementations of MsgUnmarshaler interfaces
+func (unmarshaler *InsertMsgUnmarshaler) Unmarshal(input *pulsar.Message) (*TsMsg, Status)
+
+
+type QueryReqUnmarshaler struct {}
+
+// implementations of MsgUnmarshaler interfaces
+func (unmarshaler *QueryReqUnmarshaler) Unmarshal(input *pulsar.Message) (*TsMsg, Status)
+```
+
+
+
+#### 8.3 Query Node
+
+
+
+
+
+
+
+
+
+## 4. Storage Engine
+
+
+
+#### 4.X Interfaces
+
+
+
+
+
+## 5. Master
+
+
+
+#### 5.X Interfaces
+
+
+
+
+
--- a/docs/developer_guides/figs/data_organization.pdf
+++ b/docs/developer_guides/figs/data_organization.pdf
--- a/docs/developer_guides/figs/hlc.pdf
+++ b/docs/developer_guides/figs/hlc.pdf
--- a/docs/developer_guides/figs/hlc.png
+++ b/docs/developer_guides/figs/hlc.png
--- a/docs/developer_guides/figs/state_sync.pdf
+++ b/docs/developer_guides/figs/state_sync.pdf
--- a/docs/developer_guides/figs/system_framework.pdf
+++ b/docs/developer_guides/figs/system_framework.pdf
--- a/internal/msgclient/msgclient.go
+++ b/internal/msgclient/msgclient.go
@ -34,7 +34,7 @@ type ReaderMessageClient struct {

 	// message channel
 	searchChan  chan *msgpb.SearchMsg
-	key2SegChan chan *msgpb.Key2SegMsg
+	Key2SegChan chan *msgpb.Key2SegMsg

 	// pulsar
 	client pulsar.Client
@ -130,7 +130,7 @@ func (mc *ReaderMessageClient) receiveKey2SegMsg() {
 			if err != nil {
 				log.Fatal(err)
 			}
-			mc.key2SegChan <- &key2SegMsg
+			mc.Key2SegChan <- &key2SegMsg
 			mc.key2segConsumer.Ack(msg)
 		}
 	}
@ -235,7 +235,7 @@ func (mc *ReaderMessageClient) InitClient(ctx context.Context, url string) {

 	// init channel
 	mc.searchChan = make(chan *msgpb.SearchMsg, conf.Config.Reader.SearchChanSize)
-	mc.key2SegChan = make(chan *msgpb.Key2SegMsg, conf.Config.Reader.Key2SegChanSize)
+	mc.Key2SegChan = make(chan *msgpb.Key2SegMsg, conf.Config.Reader.Key2SegChanSize)

 	mc.InsertOrDeleteMsg = make([]*msgpb.InsertOrDeleteMsg, 0)
 	mc.Key2SegMsg = make([]*msgpb.Key2SegMsg, 0)
@ -335,9 +335,9 @@ func (mc *ReaderMessageClient) PrepareBatchMsg() []int {

 func (mc *ReaderMessageClient) PrepareKey2SegmentMsg() {
 	mc.Key2SegMsg = mc.Key2SegMsg[:0]
-	msgLen := len(mc.key2SegChan)
+	msgLen := len(mc.Key2SegChan)
 	for i := 0; i < msgLen; i++ {
-		msg := <-mc.key2SegChan
+		msg := <-mc.Key2SegChan
 		mc.Key2SegMsg = append(mc.Key2SegMsg, msg)
 	}
 }
--- a/internal/reader/collection.go
+++ b/internal/reader/collection.go
@ -22,9 +22,9 @@ type Collection struct {

 func (c *Collection) NewPartition(partitionName string) *Partition {
 	/*
-	CPartition
-	NewPartition(CCollection collection, const char* partition_name);
-	 */
+		CPartition
+		NewPartition(CCollection collection, const char* partition_name);
+	*/
 	cName := C.CString(partitionName)
 	partitionPtr := C.NewPartition(c.CollectionPtr, cName)

@ -33,13 +33,25 @@ func (c *Collection) NewPartition(partitionName string) *Partition {
 	return newPartition
 }

-func (c *Collection) DeletePartition(partition *Partition) {
+func (c *Collection) DeletePartition(node *QueryNode, partition *Partition) {
 	/*
-	void
-	DeletePartition(CPartition partition);
-	 */
+		void
+		DeletePartition(CPartition partition);
+	*/
 	cPtr := partition.PartitionPtr
 	C.DeletePartition(cPtr)

-	// TODO: remove from c.Partitions
+	tmpPartitions := make([]*Partition, 0)
+
+	for _, p := range c.Partitions {
+		if p.PartitionName == partition.PartitionName {
+			for _, s := range p.Segments {
+				delete(node.SegmentsMap, s.SegmentId)
+			}
+		} else {
+			tmpPartitions = append(tmpPartitions, p)
+		}
+	}
+
+	c.Partitions = tmpPartitions
 }
--- a/internal/reader/collection_test.go
+++ b/internal/reader/collection_test.go
@ -0,0 +1,37 @@
+package reader
+
+import (
+	"context"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestCollection_NewPartition(t *testing.T) {
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, collection.CollectionID, uint64(0))
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, len(collection.Partitions), 1)
+}
+
+func TestCollection_DeletePartition(t *testing.T) {
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, collection.CollectionID, uint64(0))
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, len(collection.Partitions), 1)
+
+	collection.DeletePartition(node, partition)
+
+	assert.Equal(t, len(collection.Partitions), 0)
+}
--- a/internal/reader/index.go
+++ b/internal/reader/index.go
@ -18,10 +18,10 @@ import (

 type IndexConfig struct{}

-func (s *Segment) buildIndex(collection* Collection) msgPb.Status {
+func (s *Segment) BuildIndex(collection *Collection) msgPb.Status {
 	/*
-	int
-	BuildIndex(CCollection c_collection, CSegmentBase c_segment);
+		int
+		BuildIndex(CCollection c_collection, CSegmentBase c_segment);
 	*/
 	var status = C.BuildIndex(collection.CollectionPtr, s.SegmentPtr)
 	if status != 0 {
@ -30,8 +30,18 @@ func (s *Segment) buildIndex(collection* Collection) msgPb.Status {
 	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
 }

-func (s *Segment) dropIndex(fieldName string) msgPb.Status {
+func (s *Segment) DropIndex(fieldName string) msgPb.Status {
 	// WARN: Not support yet

 	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
 }
+
+func (node *QueryNode) UpdateIndexes(collection *Collection, indexConfig *string) {
+	/*
+		void
+		UpdateIndexes(CCollection c_collection, const char *index_string);
+	*/
+	cCollectionPtr := collection.CollectionPtr
+	cIndexConfig := C.CString(*indexConfig)
+	C.UpdateIndexes(cCollectionPtr, cIndexConfig)
+}
--- a/internal/reader/index_test.go
+++ b/internal/reader/index_test.go
@ -53,8 +53,148 @@ func TestIndex_BuildIndex(t *testing.T) {
 	var err = segment.SegmentInsert(offset, &ids, &timestamps, &records)
 	assert.NoError(t, err)

-	// 6. Close segment, and build index
-	err = segment.CloseSegment(collection)
+	// 6. Build index
+	segment.BuildIndex(collection)
+	//assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
+	// 7. Do search
+	var queryJson = "{\"field_name\":\"fakevec\",\"num_queries\":1,\"topK\":10}"
+	var queryRawData = make([]float32, 0)
+	for i := 0; i < DIM; i++ {
+		queryRawData = append(queryRawData, float32(i))
+	}
+	var vectorRecord = msgPb.VectorRowRecord{
+		FloatData: queryRawData,
+	}
+
+	query := node.QueryJson2Info(&queryJson)
+	var searchRes, searchErr = segment.SegmentSearch(query, timestamps[N/2], &vectorRecord)
+	assert.NoError(t, searchErr)
+	fmt.Println(searchRes)
+
+	// 8. Destruct node, collection, and segment
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
+	node.DeleteCollection(collection)
+	node.Close()
+}
+
+func TestIndex_DropIndex(t *testing.T) {
+	// 1. Construct node, collection, partition and segment
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+	var segment = partition.NewSegment(0)
+
+	// 2. Create ids and timestamps
+	ids := make([]int64, 0)
+	timestamps := make([]uint64, 0)
+
+	// 3. Create records, use schema below:
+	// schema_tmp->AddField("fakeVec", DataType::VECTOR_FLOAT, 16);
+	// schema_tmp->AddField("age", DataType::INT32);
+	const DIM = 16
+	const N = 100
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		ids = append(ids, int64(i))
+		timestamps = append(timestamps, uint64(i))
+		records = append(records, rawData)
+	}
+
+	// 4. Do PreInsert
+	var offset = segment.SegmentPreInsert(N)
+	assert.GreaterOrEqual(t, offset, int64(0))
+
+	// 5. Do Insert
+	var err = segment.SegmentInsert(offset, &ids, &timestamps, &records)
+	assert.NoError(t, err)
+
+	// 6. Build index
+	var status = segment.BuildIndex(collection)
+	//assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
+	// 7. Do search
+	var queryJson = "{\"field_name\":\"fakevec\",\"num_queries\":1,\"topK\":10}"
+	var queryRawData = make([]float32, 0)
+	for i := 0; i < DIM; i++ {
+		queryRawData = append(queryRawData, float32(i))
+	}
+	var vectorRecord = msgPb.VectorRowRecord{
+		FloatData: queryRawData,
+	}
+
+	query := node.QueryJson2Info(&queryJson)
+	var searchRes, searchErr = segment.SegmentSearch(query, timestamps[N/2], &vectorRecord)
+	assert.NoError(t, searchErr)
+	fmt.Println(searchRes)
+
+	// 8. Drop index
+	status = segment.DropIndex("fakevec")
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
+	// 9. Destruct node, collection, and segment
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
+	node.DeleteCollection(collection)
+	node.Close()
+}
+
+func TestIndex_UpdateIndex(t *testing.T) {
+	// 1. Construct node, collection, partition and segment
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+	var segment = partition.NewSegment(0)
+
+	// 2. Create ids and timestamps
+	ids := make([]int64, 0)
+	timestamps := make([]uint64, 0)
+
+	// 3. Create records, use schema below:
+	// schema_tmp->AddField("fakeVec", DataType::VECTOR_FLOAT, 16);
+	// schema_tmp->AddField("age", DataType::INT32);
+	const DIM = 16
+	const N = 100
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		ids = append(ids, int64(i))
+		timestamps = append(timestamps, uint64(i))
+		records = append(records, rawData)
+	}
+
+	// 4. Do PreInsert
+	var offset = segment.SegmentPreInsert(N)
+	assert.GreaterOrEqual(t, offset, int64(0))
+
+	// 5. Do Insert
+	var err = segment.SegmentInsert(offset, &ids, &timestamps, &records)
+	assert.NoError(t, err)
+
+	// 6. Build index
+	segment.BuildIndex(collection)
 	assert.NoError(t, err)

 	// 7. Do search
@ -72,9 +212,13 @@ func TestIndex_BuildIndex(t *testing.T) {
 	assert.NoError(t, searchErr)
 	fmt.Println(searchRes)

-	// 8. Destruct node, collection, and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	// 8. UpdateIndex
+	newIndex := ""
+	node.UpdateIndexes(collection, &newIndex)
+
+	// 9. Destruct node, collection, and segment
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)
 	node.Close()
 }
--- a/internal/reader/insert_and_delete.go
+++ b/internal/reader/insert_and_delete.go
@ -0,0 +1,238 @@
+package reader
+
+import (
+	"fmt"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"log"
+	"sync"
+)
+
+func (node *QueryNode) MessagesPreprocess(insertDeleteMessages []*msgPb.InsertOrDeleteMsg, timeRange TimeRange) msgPb.Status {
+	var tMax = timeRange.timestampMax
+
+	// 1. Extract messages before readTimeSync from QueryNodeDataBuffer.
+	//    Set valid bitmap to false.
+	//    If segmentId dose not exist in segments map, creating an new segment.
+	for i, msg := range node.buffer.InsertDeleteBuffer {
+		if msg.Timestamp < tMax {
+			if !node.FoundSegmentBySegmentID(msg.SegmentId) {
+				collection, _ := node.GetCollectionByCollectionName(msg.CollectionName)
+				if collection != nil {
+					partition := collection.GetPartitionByName(msg.PartitionTag)
+					if partition != nil {
+						newSegment := partition.NewSegment(msg.SegmentId)
+						node.SegmentsMap[msg.SegmentId] = newSegment
+					} else {
+						log.Fatal("Cannot find partition:", msg.PartitionTag)
+					}
+				} else {
+					log.Fatal("Cannot find collection:", msg.CollectionName)
+				}
+			}
+			if msg.Op == msgPb.OpType_INSERT {
+				if msg.RowsData == nil {
+					continue
+				}
+				node.insertData.insertIDs[msg.SegmentId] = append(node.insertData.insertIDs[msg.SegmentId], msg.Uid)
+				node.insertData.insertTimestamps[msg.SegmentId] = append(node.insertData.insertTimestamps[msg.SegmentId], msg.Timestamp)
+				node.insertData.insertRecords[msg.SegmentId] = append(node.insertData.insertRecords[msg.SegmentId], msg.RowsData.Blob)
+			} else if msg.Op == msgPb.OpType_DELETE {
+				var r = DeleteRecord{
+					entityID:  msg.Uid,
+					timestamp: msg.Timestamp,
+				}
+				node.deletePreprocessData.deleteRecords = append(node.deletePreprocessData.deleteRecords, &r)
+				node.deletePreprocessData.count++
+			}
+			node.buffer.validInsertDeleteBuffer[i] = false
+		}
+	}
+
+	// 2. Remove invalid messages from buffer.
+	tmpInsertOrDeleteBuffer := make([]*msgPb.InsertOrDeleteMsg, 0)
+	for i, isValid := range node.buffer.validInsertDeleteBuffer {
+		if isValid {
+			tmpInsertOrDeleteBuffer = append(tmpInsertOrDeleteBuffer, node.buffer.InsertDeleteBuffer[i])
+		}
+	}
+	node.buffer.InsertDeleteBuffer = tmpInsertOrDeleteBuffer
+
+	// 3. Resize the valid bitmap and set all bits to true.
+	node.buffer.validInsertDeleteBuffer = node.buffer.validInsertDeleteBuffer[:len(node.buffer.InsertDeleteBuffer)]
+	for i := range node.buffer.validInsertDeleteBuffer {
+		node.buffer.validInsertDeleteBuffer[i] = true
+	}
+
+	// 4. Extract messages before readTimeSync from current messageClient.
+	//    Move massages after readTimeSync to QueryNodeDataBuffer.
+	//    Set valid bitmap to true.
+	//    If segmentId dose not exist in segments map, creating an new segment.
+	for _, msg := range insertDeleteMessages {
+		if msg.Timestamp < tMax {
+			if !node.FoundSegmentBySegmentID(msg.SegmentId) {
+				collection, _ := node.GetCollectionByCollectionName(msg.CollectionName)
+				if collection != nil {
+					partition := collection.GetPartitionByName(msg.PartitionTag)
+					if partition != nil {
+						newSegment := partition.NewSegment(msg.SegmentId)
+						node.SegmentsMap[msg.SegmentId] = newSegment
+					} else {
+						log.Fatal("Cannot find partition:", msg.PartitionTag)
+					}
+				} else {
+					log.Fatal("Cannot find collection:", msg.CollectionName)
+				}
+			}
+			if msg.Op == msgPb.OpType_INSERT {
+				if msg.RowsData == nil {
+					continue
+				}
+				node.insertData.insertIDs[msg.SegmentId] = append(node.insertData.insertIDs[msg.SegmentId], msg.Uid)
+				node.insertData.insertTimestamps[msg.SegmentId] = append(node.insertData.insertTimestamps[msg.SegmentId], msg.Timestamp)
+				node.insertData.insertRecords[msg.SegmentId] = append(node.insertData.insertRecords[msg.SegmentId], msg.RowsData.Blob)
+			} else if msg.Op == msgPb.OpType_DELETE {
+				var r = DeleteRecord{
+					entityID:  msg.Uid,
+					timestamp: msg.Timestamp,
+				}
+				node.deletePreprocessData.deleteRecords = append(node.deletePreprocessData.deleteRecords, &r)
+				node.deletePreprocessData.count++
+			}
+		} else {
+			node.buffer.InsertDeleteBuffer = append(node.buffer.InsertDeleteBuffer, msg)
+			node.buffer.validInsertDeleteBuffer = append(node.buffer.validInsertDeleteBuffer, true)
+		}
+	}
+
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
+
+func (node *QueryNode) WriterDelete() msgPb.Status {
+	// TODO: set timeout
+	for {
+		if node.deletePreprocessData.count == 0 {
+			return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+		}
+		node.messageClient.PrepareKey2SegmentMsg()
+		var ids, timestamps, segmentIDs = node.GetKey2Segments()
+		for i := 0; i < len(*ids); i++ {
+			id := (*ids)[i]
+			timestamp := (*timestamps)[i]
+			segmentID := (*segmentIDs)[i]
+			for _, r := range node.deletePreprocessData.deleteRecords {
+				if r.timestamp == timestamp && r.entityID == id {
+					r.segmentID = segmentID
+					node.deletePreprocessData.count--
+				}
+			}
+		}
+	}
+}
+
+func (node *QueryNode) PreInsertAndDelete() msgPb.Status {
+	// 1. Do PreInsert
+	for segmentID := range node.insertData.insertRecords {
+		var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
+		if err != nil {
+			fmt.Println(err.Error())
+			return msgPb.Status{ErrorCode: 1}
+		}
+
+		var numOfRecords = len(node.insertData.insertRecords[segmentID])
+		var offset = targetSegment.SegmentPreInsert(numOfRecords)
+		node.insertData.insertOffset[segmentID] = offset
+	}
+
+	// 2. Sort delete preprocess data by segment id
+	for _, r := range node.deletePreprocessData.deleteRecords {
+		node.deleteData.deleteIDs[r.segmentID] = append(node.deleteData.deleteIDs[r.segmentID], r.entityID)
+		node.deleteData.deleteTimestamps[r.segmentID] = append(node.deleteData.deleteTimestamps[r.segmentID], r.timestamp)
+	}
+
+	// 3. Do PreDelete
+	for segmentID := range node.deleteData.deleteIDs {
+		if segmentID < 0 {
+			continue
+		}
+		var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
+		if err != nil {
+			fmt.Println(err.Error())
+			return msgPb.Status{ErrorCode: 1}
+		}
+
+		var numOfRecords = len(node.deleteData.deleteIDs[segmentID])
+		var offset = targetSegment.SegmentPreDelete(numOfRecords)
+		node.deleteData.deleteOffset[segmentID] = offset
+	}
+
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
+
+func (node *QueryNode) DoInsertAndDelete() msgPb.Status {
+	var wg sync.WaitGroup
+	// Do insert
+	for segmentID := range node.insertData.insertRecords {
+		wg.Add(1)
+		go node.DoInsert(segmentID, &wg)
+	}
+
+	// Do delete
+	for segmentID, deleteIDs := range node.deleteData.deleteIDs {
+		if segmentID < 0 {
+			continue
+		}
+		wg.Add(1)
+		var deleteTimestamps = node.deleteData.deleteTimestamps[segmentID]
+		go node.DoDelete(segmentID, &deleteIDs, &deleteTimestamps, &wg)
+		fmt.Println("Do delete done")
+	}
+
+	wg.Wait()
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
+
+func (node *QueryNode) DoInsert(segmentID int64, wg *sync.WaitGroup) msgPb.Status {
+	var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
+	if err != nil {
+		fmt.Println(err.Error())
+		return msgPb.Status{ErrorCode: 1}
+	}
+
+	ids := node.insertData.insertIDs[segmentID]
+	timestamps := node.insertData.insertTimestamps[segmentID]
+	records := node.insertData.insertRecords[segmentID]
+	offsets := node.insertData.insertOffset[segmentID]
+
+	err = targetSegment.SegmentInsert(offsets, &ids, &timestamps, &records)
+	fmt.Println("Do insert done, len = ", len(node.insertData.insertIDs[segmentID]))
+
+	node.QueryLog(len(ids))
+
+	if err != nil {
+		fmt.Println(err.Error())
+		return msgPb.Status{ErrorCode: 1}
+	}
+
+	wg.Done()
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
+
+func (node *QueryNode) DoDelete(segmentID int64, deleteIDs *[]int64, deleteTimestamps *[]uint64, wg *sync.WaitGroup) msgPb.Status {
+	var segment, err = node.GetSegmentBySegmentID(segmentID)
+	if err != nil {
+		fmt.Println(err.Error())
+		return msgPb.Status{ErrorCode: 1}
+	}
+
+	offset := node.deleteData.deleteOffset[segmentID]
+
+	node.msgCounter.DeleteCounter += int64(len(*deleteIDs))
+	err = segment.SegmentDelete(offset, deleteIDs, deleteTimestamps)
+	if err != nil {
+		fmt.Println(err.Error())
+		return msgPb.Status{ErrorCode: 1}
+	}
+
+	wg.Done()
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
--- a/internal/reader/insert_and_delete_test.go
+++ b/internal/reader/insert_and_delete_test.go
@ -0,0 +1,668 @@
+package reader
+
+import (
+	"context"
+	"encoding/binary"
+	"github.com/stretchr/testify/assert"
+	"github.com/zilliztech/milvus-distributed/internal/conf"
+	"github.com/zilliztech/milvus-distributed/internal/msgclient"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"math"
+	"strconv"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestInsertAndDelete_MessagesPreprocess(t *testing.T) {
+	ctx := context.Background()
+
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_INSERT,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	assert.Equal(t, len(node.insertData.insertIDs), msgLength)
+	assert.Equal(t, len(node.insertData.insertTimestamps), msgLength)
+	assert.Equal(t, len(node.insertData.insertRecords), msgLength)
+	assert.Equal(t, len(node.insertData.insertOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.Close()
+}
+
+// NOTE: start pulsar before test
+func TestInsertAndDelete_WriterDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+	mc.InitClient(ctx, pulsarAddr)
+
+	mc.ReceiveMessage()
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_DELETE,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	for i := 0; i < msgLength; i++ {
+		key2SegMsg := msgPb.Key2SegMsg{
+			Uid:       int64(i),
+			Timestamp: uint64(i + 1000),
+			SegmentId: []int64{int64(i)},
+		}
+		node.messageClient.Key2SegChan <- &key2SegMsg
+	}
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), 0)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), 0)
+	assert.Equal(t, len(node.deleteData.deleteOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength)
+	assert.Equal(t, node.deletePreprocessData.count, int32(msgLength))
+
+	node.WriterDelete()
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength)
+	assert.Equal(t, node.deletePreprocessData.count, int32(0))
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.Close()
+}
+
+// NOTE: start pulsar before test
+func TestInsertAndDelete_PreInsertAndDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+	mc.InitClient(ctx, pulsarAddr)
+
+	mc.ReceiveMessage()
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength/2; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_INSERT,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	for i := 0; i < msgLength/2; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i + msgLength/2),
+			ChannelId:    0,
+			Op:           msgPb.OpType_DELETE,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	for i := 0; i < msgLength; i++ {
+		key2SegMsg := msgPb.Key2SegMsg{
+			Uid:       int64(i),
+			Timestamp: uint64(i + 1000),
+			SegmentId: []int64{int64(i)},
+		}
+		node.messageClient.Key2SegChan <- &key2SegMsg
+	}
+
+	assert.Equal(t, len(node.insertData.insertIDs), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertTimestamps), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertRecords), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertOffset), 0)
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), 0)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), 0)
+	assert.Equal(t, len(node.deleteData.deleteOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength/2)
+	assert.Equal(t, node.deletePreprocessData.count, int32(msgLength/2))
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.WriterDelete()
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength/2)
+	assert.Equal(t, node.deletePreprocessData.count, int32(0))
+
+	node.PreInsertAndDelete()
+
+	assert.Equal(t, len(node.insertData.insertOffset), msgLength/2)
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), msgLength/2)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), msgLength/2)
+	assert.Equal(t, len(node.deleteData.deleteOffset), msgLength/2)
+
+	node.Close()
+}
+
+func TestInsertAndDelete_DoInsert(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_INSERT,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	assert.Equal(t, len(node.insertData.insertIDs), msgLength)
+	assert.Equal(t, len(node.insertData.insertTimestamps), msgLength)
+	assert.Equal(t, len(node.insertData.insertRecords), msgLength)
+	assert.Equal(t, len(node.insertData.insertOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.PreInsertAndDelete()
+
+	assert.Equal(t, len(node.insertData.insertOffset), msgLength)
+
+	wg := sync.WaitGroup{}
+	for segmentID := range node.insertData.insertRecords {
+		wg.Add(1)
+		go node.DoInsert(segmentID, &wg)
+	}
+	wg.Wait()
+
+	node.Close()
+}
+
+// NOTE: start pulsar before test
+func TestInsertAndDelete_DoDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+	mc.InitClient(ctx, pulsarAddr)
+
+	mc.ReceiveMessage()
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_DELETE,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	for i := 0; i < msgLength; i++ {
+		key2SegMsg := msgPb.Key2SegMsg{
+			Uid:       int64(i),
+			Timestamp: uint64(i + 1000),
+			SegmentId: []int64{int64(i)},
+		}
+		node.messageClient.Key2SegChan <- &key2SegMsg
+	}
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), 0)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), 0)
+	assert.Equal(t, len(node.deleteData.deleteOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength)
+	assert.Equal(t, node.deletePreprocessData.count, int32(msgLength))
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.WriterDelete()
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength)
+	assert.Equal(t, node.deletePreprocessData.count, int32(0))
+
+	node.PreInsertAndDelete()
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), msgLength)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), msgLength)
+	assert.Equal(t, len(node.deleteData.deleteOffset), msgLength)
+
+	wg := sync.WaitGroup{}
+	for segmentID, deleteIDs := range node.deleteData.deleteIDs {
+		if segmentID < 0 {
+			continue
+		}
+		wg.Add(1)
+		var deleteTimestamps = node.deleteData.deleteTimestamps[segmentID]
+		go node.DoDelete(segmentID, &deleteIDs, &deleteTimestamps, &wg)
+	}
+	wg.Wait()
+
+	node.Close()
+}
+
+// NOTE: start pulsar before test
+func TestInsertAndDelete_DoInsertAndDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+	mc.InitClient(ctx, pulsarAddr)
+
+	mc.ReceiveMessage()
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength/2; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_INSERT,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	for i := 0; i < msgLength/2; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i + msgLength/2),
+			ChannelId:    0,
+			Op:           msgPb.OpType_DELETE,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	for i := 0; i < msgLength; i++ {
+		key2SegMsg := msgPb.Key2SegMsg{
+			Uid:       int64(i),
+			Timestamp: uint64(i + 1000),
+			SegmentId: []int64{int64(i)},
+		}
+		node.messageClient.Key2SegChan <- &key2SegMsg
+	}
+
+	assert.Equal(t, len(node.insertData.insertIDs), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertTimestamps), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertRecords), msgLength/2)
+	assert.Equal(t, len(node.insertData.insertOffset), 0)
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), 0)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), 0)
+	assert.Equal(t, len(node.deleteData.deleteOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength/2)
+	assert.Equal(t, node.deletePreprocessData.count, int32(msgLength/2))
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.WriterDelete()
+
+	assert.Equal(t, len(node.deletePreprocessData.deleteRecords), msgLength/2)
+	assert.Equal(t, node.deletePreprocessData.count, int32(0))
+
+	node.PreInsertAndDelete()
+
+	assert.Equal(t, len(node.insertData.insertOffset), msgLength/2)
+
+	assert.Equal(t, len(node.deleteData.deleteIDs), msgLength/2)
+	assert.Equal(t, len(node.deleteData.deleteTimestamps), msgLength/2)
+	assert.Equal(t, len(node.deleteData.deleteOffset), msgLength/2)
+
+	status := node.DoInsertAndDelete()
+
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
+	node.Close()
+}
--- a/internal/reader/meta.go
+++ b/internal/reader/meta.go
@ -11,20 +11,20 @@ import (
 	"time"

 	"github.com/zilliztech/milvus-distributed/internal/conf"
+	"github.com/zilliztech/milvus-distributed/internal/master/collection"
 	"github.com/zilliztech/milvus-distributed/internal/master/kv"
 	"github.com/zilliztech/milvus-distributed/internal/master/segment"
-	"github.com/zilliztech/milvus-distributed/internal/master/collection"
 	"go.etcd.io/etcd/clientv3"
 	"go.etcd.io/etcd/mvcc/mvccpb"
 )

 const (
-	CollectonPrefix = "/collection/"
-	SegmentPrefix   = "/segment/"
+	CollectionPrefix = "/collection/"
+	SegmentPrefix    = "/segment/"
 )

 func GetCollectionObjId(key string) string {
-	prefix := path.Join(conf.Config.Etcd.Rootpath, CollectonPrefix) + "/"
+	prefix := path.Join(conf.Config.Etcd.Rootpath, CollectionPrefix) + "/"
 	return strings.TrimPrefix(key, prefix)
 }

@ -34,7 +34,7 @@ func GetSegmentObjId(key string) string {
 }

 func isCollectionObj(key string) bool {
-	prefix := path.Join(conf.Config.Etcd.Rootpath, CollectonPrefix) + "/"
+	prefix := path.Join(conf.Config.Etcd.Rootpath, CollectionPrefix) + "/"
 	prefix = strings.TrimSpace(prefix)
 	// println("prefix is :$", prefix)
 	index := strings.Index(key, prefix)
@ -122,7 +122,7 @@ func (node *QueryNode) processSegmentCreate(id string, value string) {
 			newSegmentID := int64(segment.SegmentID) // todo change all to uint64
 			// start new segment and add it into partition.OpenedSegments
 			newSegment := partition.NewSegment(newSegmentID)
-			newSegment.SegmentStatus = SegmentOpened
+			// newSegment.SegmentStatus = SegmentOpened
 			newSegment.SegmentCloseTime = segment.CloseTimeStamp
 			node.SegmentsMap[newSegmentID] = newSegment
 		}
@ -195,10 +195,32 @@ func (node *QueryNode) processModify(key string, msg string) {
 func (node *QueryNode) processSegmentDelete(id string) {
 	println("Delete segment: ", id)

+	segmentId, err := strconv.ParseInt(id, 10, 64)
+	if err != nil {
+		log.Println("Cannot parse segment id:" + id)
+	}
+
+	for _, col := range node.Collections {
+		for _, p := range col.Partitions {
+			for _, s := range p.Segments {
+				if s.SegmentId == segmentId {
+					p.DeleteSegment(node, s)
+				}
+			}
+		}
+	}
 }

 func (node *QueryNode) processCollectionDelete(id string) {
 	println("Delete collection: ", id)
+
+	collectionId, err := strconv.ParseInt(id, 10, 64)
+	if err != nil {
+		log.Println("Cannot parse collection id:" + id)
+	}
+
+	targetCollection := node.GetCollectionByID(uint64(collectionId))
+	node.DeleteCollection(targetCollection)
 }

 func (node *QueryNode) processDelete(key string) {
@ -241,7 +263,7 @@ func (node *QueryNode) processResp(resp clientv3.WatchResponse) error {
 }

 func (node *QueryNode) loadCollections() error {
-	keys, values := node.kvBase.LoadWithPrefix(CollectonPrefix)
+	keys, values := node.kvBase.LoadWithPrefix(CollectionPrefix)
 	for i := range keys {
 		objID := GetCollectionObjId(keys[i])
 		node.processCollectionCreate(objID, values[i])
--- a/internal/reader/meta_test.go
+++ b/internal/reader/meta_test.go
@ -0,0 +1,606 @@
+package reader
+
+import (
+	"context"
+	"github.com/stretchr/testify/assert"
+	"github.com/zilliztech/milvus-distributed/internal/conf"
+	"github.com/zilliztech/milvus-distributed/internal/master/collection"
+	"github.com/zilliztech/milvus-distributed/internal/master/segment"
+	"github.com/zilliztech/milvus-distributed/internal/msgclient"
+	"github.com/zilliztech/milvus-distributed/internal/proto/master"
+	messagePb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"log"
+	"math"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestMeta_GetCollectionObjId(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	var key = "/collection/collection0"
+	var collectionObjId1 = GetCollectionObjId(key)
+
+	assert.Equal(t, collectionObjId1, "/collection/collection0")
+
+	key = "fakeKey"
+	var collectionObjId2 = GetCollectionObjId(key)
+
+	assert.Equal(t, collectionObjId2, "fakeKey")
+}
+
+func TestMeta_GetSegmentObjId(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	var key = "/segment/segment0"
+	var segmentObjId1 = GetSegmentObjId(key)
+
+	assert.Equal(t, segmentObjId1, "/segment/segment0")
+
+	key = "fakeKey"
+	var segmentObjId2 = GetSegmentObjId(key)
+
+	assert.Equal(t, segmentObjId2, "fakeKey")
+}
+
+func TestMeta_isCollectionObj(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	var key = "by-dev/collection/collection0"
+	var b1 = isCollectionObj(key)
+
+	assert.Equal(t, b1, true)
+
+	key = "by-dev/segment/segment0"
+	var b2 = isCollectionObj(key)
+
+	assert.Equal(t, b2, false)
+}
+
+func TestMeta_isSegmentObj(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	var key = "by-dev/segment/segment0"
+	var b1 = isSegmentObj(key)
+
+	assert.Equal(t, b1, true)
+
+	key = "by-dev/collection/collection0"
+	var b2 = isSegmentObj(key)
+
+	assert.Equal(t, b2, false)
+}
+
+func TestMeta_isSegmentChannelRangeInQueryNodeChannelRange(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	var s = segment.Segment{
+		SegmentID:      uint64(0),
+		CollectionID:   uint64(0),
+		PartitionTag:   "partition0",
+		ChannelStart:   0,
+		ChannelEnd:     128,
+		OpenTimeStamp:  uint64(0),
+		CloseTimeStamp: uint64(math.MaxUint64),
+		CollectionName: "collection0",
+		Status:         master.SegmentStatus_OPENED,
+		Rows:           int64(0),
+	}
+
+	var b = isSegmentChannelRangeInQueryNodeChannelRange(&s)
+	assert.Equal(t, b, true)
+
+	s = segment.Segment{
+		SegmentID:      uint64(0),
+		CollectionID:   uint64(0),
+		PartitionTag:   "partition0",
+		ChannelStart:   128,
+		ChannelEnd:     256,
+		OpenTimeStamp:  uint64(0),
+		CloseTimeStamp: uint64(math.MaxUint64),
+		CollectionName: "collection0",
+		Status:         master.SegmentStatus_OPENED,
+		Rows:           int64(0),
+	}
+
+	b = isSegmentChannelRangeInQueryNodeChannelRange(&s)
+	assert.Equal(t, b, false)
+}
+
+func TestMeta_PrintCollectionStruct(t *testing.T) {
+	var age = collection.FieldMeta{
+		FieldName: "age",
+		Type:      messagePb.DataType_INT32,
+		DIM:       int64(1),
+	}
+
+	var vec = collection.FieldMeta{
+		FieldName: "vec",
+		Type:      messagePb.DataType_VECTOR_FLOAT,
+		DIM:       int64(16),
+	}
+
+	var fieldMetas = []collection.FieldMeta{age, vec}
+
+	var c = collection.Collection{
+		ID:         uint64(0),
+		Name:       "collection0",
+		CreateTime: uint64(0),
+		Schema:     fieldMetas,
+		SegmentIDs: []uint64{
+			0, 1, 2,
+		},
+		PartitionTags: []string{
+			"partition0",
+		},
+		GrpcMarshalString: "",
+		IndexParam:        nil,
+	}
+
+	printCollectionStruct(&c)
+}
+
+func TestMeta_PrintSegmentStruct(t *testing.T) {
+	var s = segment.Segment{
+		SegmentID:      uint64(0),
+		CollectionID:   uint64(0),
+		PartitionTag:   "partition0",
+		ChannelStart:   128,
+		ChannelEnd:     256,
+		OpenTimeStamp:  uint64(0),
+		CloseTimeStamp: uint64(math.MaxUint64),
+		CollectionName: "collection0",
+		Status:         master.SegmentStatus_OPENED,
+		Rows:           int64(0),
+	}
+
+	printSegmentStruct(&s)
+}
+
+func TestMeta_ProcessCollectionCreate(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCollectionCreate(id, value)
+	c := node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+}
+
+func TestMeta_ProcessSegmentCreate(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	c := node.NewCollection(uint64(0), "test", "")
+	c.NewPartition("default")
+
+	node.processSegmentCreate(id, value)
+	s := node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+}
+
+func TestMeta_ProcessCreate(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	key1 := "by-dev/collection/0"
+	msg1 := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCreate(key1, msg1)
+	c := node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	key2 := "by-dev/segment/0"
+	msg2 := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	node.processCreate(key2, msg2)
+	s := node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+}
+
+func TestMeta_ProcessSegmentModify(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	var c = node.NewCollection(uint64(0), "test", "")
+	c.NewPartition("default")
+
+	node.processSegmentCreate(id, value)
+	var s = node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+
+	newValue := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177888," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	node.processSegmentModify(id, newValue)
+	s = node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177888))
+	assert.Equal(t, s.SegmentStatus, 0)
+}
+
+func TestMeta_ProcessCollectionModify(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCollectionCreate(id, value)
+	var c = node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	// TODO: use different index for testing processCollectionModify
+	newValue := "{\"id\":0,\"name\":\"test_new\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCollectionModify(id, newValue)
+	c = node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+}
+
+func TestMeta_ProcessModify(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	key1 := "by-dev/collection/0"
+	msg1 := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCreate(key1, msg1)
+	c := node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	key2 := "by-dev/segment/0"
+	msg2 := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	node.processCreate(key2, msg2)
+	s := node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+
+	// modify
+	// TODO: use different index for testing processCollectionModify
+	msg3 := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processModify(key1, msg3)
+	c = node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	msg4 := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177888," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	node.processModify(key2, msg4)
+	s = node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177888))
+	assert.Equal(t, s.SegmentStatus, 0)
+}
+
+func TestMeta_ProcessSegmentDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	c := node.NewCollection(uint64(0), "test", "")
+	c.NewPartition("default")
+
+	node.processSegmentCreate(id, value)
+	s := node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+
+	node.processSegmentDelete("0")
+	mapSize := len(node.SegmentsMap)
+
+	assert.Equal(t, mapSize, 0)
+}
+
+func TestMeta_ProcessCollectionDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	id := "0"
+	value := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCollectionCreate(id, value)
+	c := node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	node.processCollectionDelete(id)
+	collectionsSize := len(node.Collections)
+
+	assert.Equal(t, collectionsSize, 0)
+}
+
+func TestMeta_ProcessDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	key1 := "by-dev/collection/0"
+	msg1 := "{\"id\":0,\"name\":\"test\",\"creat_time\":1603359905,\"schema\":" +
+		"[{\"field_name\":\"age\",\"type\":4,\"dimension\":1}," +
+		"{\"field_name\":\"field_vec\",\"type\":101,\"dimension\":512}]," +
+		"\"segment_ids\":[6886378356295345384],\"partition_tags\":[\"default\"]," +
+		"\"grpc_marshal_string\":\"id: 6886378356295345384\\nname: \\\"test\\\"\\nschema: \\u003c\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"age\\\"\\n    type: INT32\\n    dim: 1\\n  \\u003e\\n  " +
+		"field_metas: \\u003c\\n    field_name: \\\"field_vec\\\"\\n    type: VECTOR_FLOAT\\n    " +
+		"dim: 512\\n  \\u003e\\n\\u003e\\ncreate_time: 1603359905\\nsegment_ids: " +
+		"6886378356295345384\\npartition_tags: \\\"default\\\"\\n\",\"index_param\":null}"
+
+	node.processCreate(key1, msg1)
+	c := node.Collections[0]
+
+	assert.Equal(t, c.CollectionName, "test")
+	assert.Equal(t, c.CollectionID, uint64(0))
+
+	key2 := "by-dev/segment/0"
+	msg2 := "{\"segment_id\":0,\"collection_id\":0," +
+		"\"partition_tag\":\"default\",\"channel_start\":0,\"channel_end\":128," +
+		"\"open_timestamp\":1603360439,\"close_timestamp\":70368744177663," +
+		"\"collection_name\":\"test\",\"segment_status\":0,\"rows\":0}"
+
+	node.processCreate(key2, msg2)
+	s := node.SegmentsMap[int64(0)]
+
+	assert.Equal(t, s.SegmentId, int64(0))
+	assert.Equal(t, s.SegmentCloseTime, uint64(70368744177663))
+	assert.Equal(t, s.SegmentStatus, 0)
+
+	node.processDelete(key1)
+	collectionsSize := len(node.Collections)
+
+	assert.Equal(t, collectionsSize, 0)
+
+	mapSize := len(node.SegmentsMap)
+
+	assert.Equal(t, mapSize, 0)
+}
+
+func TestMeta_ProcessResp(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	err := node.InitFromMeta()
+	assert.Nil(t, err)
+
+	metaChan := node.kvBase.WatchWithPrefix("")
+
+	select {
+	case <-node.ctx.Done():
+		return
+	case resp := <-metaChan:
+		_ = node.processResp(resp)
+	}
+}
+
+func TestMeta_LoadCollections(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	err := node.InitFromMeta()
+	assert.Nil(t, err)
+
+	err2 := node.loadCollections()
+	assert.Nil(t, err2)
+}
+
+func TestMeta_LoadSegments(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	err := node.InitFromMeta()
+	assert.Nil(t, err)
+
+	err2 := node.loadSegments()
+	assert.Nil(t, err2)
+}
+
+func TestMeta_InitFromMeta(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	err := node.InitFromMeta()
+	assert.Nil(t, err)
+}
+
+func TestMeta_RunMetaService(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	node := CreateQueryNode(ctx, 0, 0, nil)
+
+	wg := sync.WaitGroup{}
+	err := node.InitFromMeta()
+
+	if err != nil {
+		log.Printf("Init query node from meta failed")
+		return
+	}
+
+	wg.Add(1)
+	go node.RunMetaService(&wg)
+	wg.Wait()
+
+	node.Close()
+}
--- a/internal/reader/partition.go
+++ b/internal/reader/partition.go
@ -31,7 +31,7 @@ func (p *Partition) NewSegment(segmentId int64) *Segment {
 	return newSegment
 }

-func (p *Partition) DeleteSegment(segment *Segment) {
+func (p *Partition) DeleteSegment(node *QueryNode, segment *Segment) {
 	/*
 		void
 		DeleteSegment(CSegmentBase segment);
@ -39,5 +39,15 @@ func (p *Partition) DeleteSegment(segment *Segment) {
 	cPtr := segment.SegmentPtr
 	C.DeleteSegment(cPtr)

-	// TODO: remove from p.Segments
+	tmpSegments := make([]*Segment, 0)
+
+	for _, s := range p.Segments {
+		if s.SegmentId == segment.SegmentId {
+			delete(node.SegmentsMap, s.SegmentId)
+		} else {
+			tmpSegments = append(tmpSegments, s)
+		}
+	}
+
+	p.Segments = tmpSegments
 }
--- a/internal/reader/partition_test.go
+++ b/internal/reader/partition_test.go
@ -0,0 +1,61 @@
+package reader
+
+import (
+	"context"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestPartition_NewSegment(t *testing.T) {
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+
+	var segment = partition.NewSegment(0)
+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, collection.CollectionID, uint64(0))
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, node.Collections[0].Partitions[0].Segments[0].SegmentId, int64(0))
+
+	assert.Equal(t, len(collection.Partitions), 1)
+	assert.Equal(t, len(node.Collections), 1)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 1)
+
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, node.FoundSegmentBySegmentID(int64(0)), true)
+}
+
+func TestPartition_DeleteSegment(t *testing.T) {
+	// 1. Construct node, collection, partition and segment
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+
+	var segment = partition.NewSegment(0)
+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, collection.CollectionID, uint64(0))
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, node.Collections[0].Partitions[0].Segments[0].SegmentId, int64(0))
+
+	assert.Equal(t, len(collection.Partitions), 1)
+	assert.Equal(t, len(node.Collections), 1)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 1)
+
+	assert.Equal(t, segment.SegmentId, int64(0))
+
+	// 2. Destruct collection, partition and segment
+	partition.DeleteSegment(node, segment)
+
+	assert.Equal(t, len(collection.Partitions), 1)
+	assert.Equal(t, len(node.Collections), 1)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 0)
+	assert.Equal(t, node.FoundSegmentBySegmentID(int64(0)), false)
+}
--- a/internal/reader/query_node.go
+++ b/internal/reader/query_node.go
@ -15,20 +15,10 @@ import "C"

 import (
 	"context"
-	"encoding/json"
-	"fmt"
-	"log"
-	"sort"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"github.com/zilliztech/milvus-distributed/internal/conf"
-	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
 	"github.com/zilliztech/milvus-distributed/internal/master/kv"
 	"github.com/zilliztech/milvus-distributed/internal/msgclient"
-	"github.com/stretchr/testify/assert"
-	//"github.com/stretchr/testify/assert"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"time"
 )

 type InsertData struct {
@ -91,10 +81,10 @@ type QueryNode struct {
 	// context
 	ctx context.Context

-	QueryNodeId   uint64
-	Collections   []*Collection
-	SegmentsMap   map[int64]*Segment
-	messageClient *msgclient.ReaderMessageClient
+	QueryNodeId          uint64
+	Collections          []*Collection
+	SegmentsMap          map[int64]*Segment
+	messageClient        *msgclient.ReaderMessageClient
 	queryNodeTimeSync    *QueryNodeTime
 	buffer               QueryNodeDataBuffer
 	deletePreprocessData DeletePreprocessData
@ -239,469 +229,19 @@ func (node *QueryNode) DeleteCollection(collection *Collection) {
 	cPtr := collection.CollectionPtr
 	C.DeleteCollection(cPtr)

-	// TODO: remove from node.Collections
-}
-
-func (node *QueryNode) UpdateIndexes(collection *Collection, indexConfig *string) {
-	/*
-		void
-		UpdateIndexes(CCollection c_collection, const char *index_string);
-	*/
-	cCollectionPtr := collection.CollectionPtr
-	cIndexConfig := C.CString(*indexConfig)
-	C.UpdateIndexes(cCollectionPtr, cIndexConfig)
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-func (node *QueryNode) PrepareBatchMsg() []int {
-	var msgLen = node.messageClient.PrepareBatchMsg()
-	return msgLen
-}
-
-func (node *QueryNode) InitQueryNodeCollection() {
-	// TODO: remove hard code, add collection creation request
-	// TODO: error handle
-	var newCollection = node.NewCollection(0, "collection1", "fakeSchema")
-	var newPartition = newCollection.NewPartition("partition1")
-	// TODO: add segment id
-	var segment = newPartition.NewSegment(0)
-	node.SegmentsMap[0] = segment
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-func (node *QueryNode) RunInsertDelete(wg *sync.WaitGroup) {
-	const Debug = true
-	const CountInsertMsgBaseline = 1000 * 1000
-	var BaselineCounter int64 = 0
-
-	if Debug {
-		for {
-			select {
-			case <-node.ctx.Done():
-				wg.Done()
-				return
-			default:
-				var msgLen = node.PrepareBatchMsg()
-				var timeRange = TimeRange{node.messageClient.TimeSyncStart(), node.messageClient.TimeSyncEnd()}
-				assert.NotEqual(nil, 0, timeRange.timestampMin)
-				assert.NotEqual(nil, 0, timeRange.timestampMax)
-
-				if node.msgCounter.InsertCounter/CountInsertMsgBaseline != BaselineCounter {
-					node.WriteQueryLog()
-					BaselineCounter = node.msgCounter.InsertCounter / CountInsertMsgBaseline
+	collectionID := collection.CollectionID
+	tmpCollections := make([]*Collection, 0)
+	for _, col := range node.Collections {
+		if col.CollectionID == collectionID {
+			for _, p := range collection.Partitions {
+				for _, s := range p.Segments {
+					delete(node.SegmentsMap, s.SegmentId)
 				}
-
-				if msgLen[0] == 0 && len(node.buffer.InsertDeleteBuffer) <= 0 {
-					node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
-					continue
-				}
-
-				node.QueryNodeDataInit()
-				node.MessagesPreprocess(node.messageClient.InsertOrDeleteMsg, timeRange)
-				//fmt.Println("MessagesPreprocess Done")
-				node.WriterDelete()
-				node.PreInsertAndDelete()
-				//fmt.Println("PreInsertAndDelete Done")
-				node.DoInsertAndDelete()
-				//fmt.Println("DoInsertAndDelete Done")
-				node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
-			}
-		}
-	} else {
-		for {
-			select {
-			case <-node.ctx.Done():
-				wg.Done()
-				return
-			default:
-				var msgLen = node.PrepareBatchMsg()
-				var timeRange = TimeRange{node.messageClient.TimeSyncStart(), node.messageClient.TimeSyncEnd()}
-				assert.NotEqual(nil, 0, timeRange.timestampMin)
-				assert.NotEqual(nil, 0, timeRange.timestampMax)
-
-				if msgLen[0] == 0 && len(node.buffer.InsertDeleteBuffer) <= 0 {
-					node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
-					continue
-				}
-
-				node.QueryNodeDataInit()
-				node.MessagesPreprocess(node.messageClient.InsertOrDeleteMsg, timeRange)
-				//fmt.Println("MessagesPreprocess Done")
-				node.WriterDelete()
-				node.PreInsertAndDelete()
-				//fmt.Println("PreInsertAndDelete Done")
-				node.DoInsertAndDelete()
-				//fmt.Println("DoInsertAndDelete Done")
-				node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
-			}
-		}
-	}
-	wg.Done()
-}
-
-func (node *QueryNode) TestInsertDelete(timeRange TimeRange) {
-	node.QueryNodeDataInit()
-	node.MessagesPreprocess(node.messageClient.InsertOrDeleteMsg, timeRange)
-	fmt.Println("MessagesPreprocess Done")
-	node.WriterDelete()
-	node.PreInsertAndDelete()
-	fmt.Println("PreInsertAndDelete Done")
-	node.DoInsertAndDelete()
-	fmt.Println("DoInsertAndDelete Done")
-	node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
-	fmt.Print("UpdateSearchTimeSync Done\n\n\n")
-}
-
-func (node *QueryNode) RunSearch(wg *sync.WaitGroup) {
-	for {
-		select {
-		case <-node.ctx.Done():
-			wg.Done()
-			return
-		case msg := <-node.messageClient.GetSearchChan():
-			node.messageClient.SearchMsg = node.messageClient.SearchMsg[:0]
-			node.messageClient.SearchMsg = append(node.messageClient.SearchMsg, msg)
-			//for  {
-			//if node.messageClient.SearchMsg[0].Timestamp < node.queryNodeTimeSync.ServiceTimeSync {
-			var status = node.Search(node.messageClient.SearchMsg)
-			fmt.Println("Do Search done")
-			if status.ErrorCode != 0 {
-				fmt.Println("Search Failed")
-				node.PublishFailedSearchResult()
-			}
-			//break
-			//}
-			//}
-		default:
-		}
-	}
-	wg.Done()
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-func (node *QueryNode) MessagesPreprocess(insertDeleteMessages []*msgPb.InsertOrDeleteMsg, timeRange TimeRange) msgPb.Status {
-	var tMax = timeRange.timestampMax
-
-	// 1. Extract messages before readTimeSync from QueryNodeDataBuffer.
-	//    Set valid bitmap to false.
-	for i, msg := range node.buffer.InsertDeleteBuffer {
-		if msg.Timestamp < tMax {
-			if msg.Op == msgPb.OpType_INSERT {
-				if msg.RowsData == nil {
-					continue
-				}
-				node.insertData.insertIDs[msg.SegmentId] = append(node.insertData.insertIDs[msg.SegmentId], msg.Uid)
-				node.insertData.insertTimestamps[msg.SegmentId] = append(node.insertData.insertTimestamps[msg.SegmentId], msg.Timestamp)
-				node.insertData.insertRecords[msg.SegmentId] = append(node.insertData.insertRecords[msg.SegmentId], msg.RowsData.Blob)
-			} else if msg.Op == msgPb.OpType_DELETE {
-				var r = DeleteRecord{
-					entityID:  msg.Uid,
-					timestamp: msg.Timestamp,
-				}
-				node.deletePreprocessData.deleteRecords = append(node.deletePreprocessData.deleteRecords, &r)
-				atomic.AddInt32(&node.deletePreprocessData.count, 1)
-			}
-			node.buffer.validInsertDeleteBuffer[i] = false
-		}
-	}
-
-	// 2. Remove invalid messages from buffer.
-	tmpInsertOrDeleteBuffer := make([]*msgPb.InsertOrDeleteMsg, 0)
-	for i, isValid := range node.buffer.validInsertDeleteBuffer {
-		if isValid {
-			tmpInsertOrDeleteBuffer = append(tmpInsertOrDeleteBuffer, node.buffer.InsertDeleteBuffer[i])
-		}
-	}
-	node.buffer.InsertDeleteBuffer = tmpInsertOrDeleteBuffer
-
-	// 3. Resize the valid bitmap and set all bits to true.
-	node.buffer.validInsertDeleteBuffer = node.buffer.validInsertDeleteBuffer[:len(node.buffer.InsertDeleteBuffer)]
-	for i := range node.buffer.validInsertDeleteBuffer {
-		node.buffer.validInsertDeleteBuffer[i] = true
-	}
-
-	// 4. Extract messages before readTimeSync from current messageClient.
-	//    Move massages after readTimeSync to QueryNodeDataBuffer.
-	//    Set valid bitmap to true.
-	for _, msg := range insertDeleteMessages {
-		if msg.Timestamp < tMax {
-			if msg.Op == msgPb.OpType_INSERT {
-				if msg.RowsData == nil {
-					continue
-				}
-				node.insertData.insertIDs[msg.SegmentId] = append(node.insertData.insertIDs[msg.SegmentId], msg.Uid)
-				node.insertData.insertTimestamps[msg.SegmentId] = append(node.insertData.insertTimestamps[msg.SegmentId], msg.Timestamp)
-				node.insertData.insertRecords[msg.SegmentId] = append(node.insertData.insertRecords[msg.SegmentId], msg.RowsData.Blob)
-			} else if msg.Op == msgPb.OpType_DELETE {
-				var r = DeleteRecord{
-					entityID:  msg.Uid,
-					timestamp: msg.Timestamp,
-				}
-				node.deletePreprocessData.deleteRecords = append(node.deletePreprocessData.deleteRecords, &r)
-				atomic.AddInt32(&node.deletePreprocessData.count, 1)
 			}
 		} else {
-			node.buffer.InsertDeleteBuffer = append(node.buffer.InsertDeleteBuffer, msg)
-			node.buffer.validInsertDeleteBuffer = append(node.buffer.validInsertDeleteBuffer, true)
+			tmpCollections = append(tmpCollections, col)
 		}
 	}

-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-}
-
-func (node *QueryNode) WriterDelete() msgPb.Status {
-	// TODO: set timeout
-	for {
-		if node.deletePreprocessData.count == 0 {
-			return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-		}
-		node.messageClient.PrepareKey2SegmentMsg()
-		var ids, timestamps, segmentIDs = node.GetKey2Segments()
-		for i := 0; i < len(*ids); i++ {
-			id := (*ids)[i]
-			timestamp := (*timestamps)[i]
-			segmentID := (*segmentIDs)[i]
-			for _, r := range node.deletePreprocessData.deleteRecords {
-				if r.timestamp == timestamp && r.entityID == id {
-					r.segmentID = segmentID
-					atomic.AddInt32(&node.deletePreprocessData.count, -1)
-				}
-			}
-		}
-	}
-}
-
-func (node *QueryNode) PreInsertAndDelete() msgPb.Status {
-	// 1. Do PreInsert
-	for segmentID := range node.insertData.insertRecords {
-		var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
-		if err != nil {
-			fmt.Println(err.Error())
-			return msgPb.Status{ErrorCode: 1}
-		}
-
-		var numOfRecords = len(node.insertData.insertRecords[segmentID])
-		var offset = targetSegment.SegmentPreInsert(numOfRecords)
-		node.insertData.insertOffset[segmentID] = offset
-	}
-
-	// 2. Sort delete preprocess data by segment id
-	for _, r := range node.deletePreprocessData.deleteRecords {
-		node.deleteData.deleteIDs[r.segmentID] = append(node.deleteData.deleteIDs[r.segmentID], r.entityID)
-		node.deleteData.deleteTimestamps[r.segmentID] = append(node.deleteData.deleteTimestamps[r.segmentID], r.timestamp)
-	}
-
-	// 3. Do PreDelete
-	for segmentID := range node.deleteData.deleteIDs {
-		if segmentID < 0 {
-			continue
-		}
-		var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
-		if err != nil {
-			fmt.Println(err.Error())
-			return msgPb.Status{ErrorCode: 1}
-		}
-
-		var numOfRecords = len(node.deleteData.deleteIDs[segmentID])
-		var offset = targetSegment.SegmentPreDelete(numOfRecords)
-		node.deleteData.deleteOffset[segmentID] = offset
-	}
-
-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-}
-
-func (node *QueryNode) DoInsertAndDelete() msgPb.Status {
-	var wg sync.WaitGroup
-	// Do insert
-	for segmentID := range node.insertData.insertRecords {
-		wg.Add(1)
-		go node.DoInsert(segmentID, &wg)
-	}
-
-	// Do delete
-	for segmentID, deleteIDs := range node.deleteData.deleteIDs {
-		if segmentID < 0 {
-			continue
-		}
-		wg.Add(1)
-		var deleteTimestamps = node.deleteData.deleteTimestamps[segmentID]
-		go node.DoDelete(segmentID, &deleteIDs, &deleteTimestamps, &wg)
-		fmt.Println("Do delete done")
-	}
-
-	wg.Wait()
-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-}
-
-func (node *QueryNode) DoInsert(segmentID int64, wg *sync.WaitGroup) msgPb.Status {
-	var targetSegment, err = node.GetSegmentBySegmentID(segmentID)
-	if err != nil {
-		fmt.Println(err.Error())
-		return msgPb.Status{ErrorCode: 1}
-	}
-
-	ids := node.insertData.insertIDs[segmentID]
-	timestamps := node.insertData.insertTimestamps[segmentID]
-	records := node.insertData.insertRecords[segmentID]
-	offsets := node.insertData.insertOffset[segmentID]
-
-	err = targetSegment.SegmentInsert(offsets, &ids, &timestamps, &records)
-	fmt.Println("Do insert done, len = ", len(node.insertData.insertIDs[segmentID]))
-
-	node.QueryLog(len(ids))
-
-	if err != nil {
-		fmt.Println(err.Error())
-		return msgPb.Status{ErrorCode: 1}
-	}
-
-	wg.Done()
-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-}
-
-func (node *QueryNode) DoDelete(segmentID int64, deleteIDs *[]int64, deleteTimestamps *[]uint64, wg *sync.WaitGroup) msgPb.Status {
-	var segment, err = node.GetSegmentBySegmentID(segmentID)
-	if err != nil {
-		fmt.Println(err.Error())
-		return msgPb.Status{ErrorCode: 1}
-	}
-
-	offset := node.deleteData.deleteOffset[segmentID]
-
-	node.msgCounter.DeleteCounter += int64(len(*deleteIDs))
-	err = segment.SegmentDelete(offset, deleteIDs, deleteTimestamps)
-	if err != nil {
-		fmt.Println(err.Error())
-		return msgPb.Status{ErrorCode: 1}
-	}
-
-	wg.Done()
-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
-}
-
-func (node *QueryNode) QueryJson2Info(queryJson *string) *QueryInfo {
-	var query QueryInfo
-	var err = json.Unmarshal([]byte(*queryJson), &query)
-
-	if err != nil {
-		log.Printf("Unmarshal query json failed")
-		return nil
-	}
-
-	//fmt.Println(query)
-	return &query
-}
-
-func (node *QueryNode) Search(searchMessages []*msgPb.SearchMsg) msgPb.Status {
-
-	type SearchResultTmp struct {
-		ResultId       int64
-		ResultDistance float32
-	}
-
-	node.msgCounter.SearchCounter += int64(len(searchMessages))
-
-	// Traverse all messages in the current messageClient.
-	// TODO: Do not receive batched search requests
-	for _, msg := range searchMessages {
-		var clientId = msg.ClientId
-		var searchTimestamp = msg.Timestamp
-
-		// ServiceTimeSync update by TimeSync, which is get from proxy.
-		// Proxy send this timestamp per `conf.Config.Timesync.Interval` milliseconds.
-		// However, timestamp of search request (searchTimestamp) is precision time.
-		// So the ServiceTimeSync is always less than searchTimestamp.
-		// Here, we manually make searchTimestamp's logic time minus `conf.Config.Timesync.Interval` milliseconds.
-		// Which means `searchTimestamp.logicTime = searchTimestamp.logicTime - conf.Config.Timesync.Interval`.
-		var logicTimestamp = searchTimestamp << 46 >> 46
-		searchTimestamp = (searchTimestamp>>18-uint64(conf.Config.Timesync.Interval+600))<<18 + logicTimestamp
-
-		var vector = msg.Records
-		// We now only the first Json is valid.
-		var queryJson = msg.Json[0]
-
-		// 1. Timestamp check
-		// TODO: return or wait? Or adding graceful time
-		if searchTimestamp > node.queryNodeTimeSync.ServiceTimeSync {
-			fmt.Println("Invalid query time, timestamp = ", searchTimestamp>>18, ", SearchTimeSync = ", node.queryNodeTimeSync.ServiceTimeSync>>18)
-			return msgPb.Status{ErrorCode: 1}
-		}
-
-		// 2. Get query information from query json
-		query := node.QueryJson2Info(&queryJson)
-		// 2d slice for receiving multiple queries's results
-		var resultsTmp = make([][]SearchResultTmp, query.NumQueries)
-		for i := 0; i < int(query.NumQueries); i++ {
-			resultsTmp[i] = make([]SearchResultTmp, 0)
-		}
-
-		// 3. Do search in all segments
-		for _, segment := range node.SegmentsMap {
-			if segment.GetRowCount() <= 0 {
-				// Skip empty segment
-				continue
-			}
-
-			//fmt.Println("Search in segment:", segment.SegmentId, ",segment rows:", segment.GetRowCount())
-			var res, err = segment.SegmentSearch(query, searchTimestamp, vector)
-			if err != nil {
-				fmt.Println(err.Error())
-				return msgPb.Status{ErrorCode: 1}
-			}
-
-			for i := 0; i < int(query.NumQueries); i++ {
-				for j := i * query.TopK; j < (i+1)*query.TopK; j++ {
-					resultsTmp[i] = append(resultsTmp[i], SearchResultTmp{
-						ResultId:       res.ResultIds[j],
-						ResultDistance: res.ResultDistances[j],
-					})
-				}
-			}
-		}
-
-		// 4. Reduce results
-		for _, rTmp := range resultsTmp {
-			sort.Slice(rTmp, func(i, j int) bool {
-				return rTmp[i].ResultDistance < rTmp[j].ResultDistance
-			})
-		}
-
-		for _, rTmp := range resultsTmp {
-			if len(rTmp) > query.TopK {
-				rTmp = rTmp[:query.TopK]
-			}
-		}
-
-		var entities = msgPb.Entities{
-			Ids: make([]int64, 0),
-		}
-		var results = msgPb.QueryResult{
-			Status: &msgPb.Status{
-				ErrorCode: 0,
-			},
-			Entities:  &entities,
-			Distances: make([]float32, 0),
-			QueryId:   uint64(msg.Uid),
-			ProxyId:  clientId,
-		}
-		for _, rTmp := range resultsTmp {
-			for _, res := range rTmp {
-				results.Entities.Ids = append(results.Entities.Ids, res.ResultId)
-				results.Distances = append(results.Distances, res.ResultDistance)
-				results.Scores = append(results.Distances, float32(0))
-			}
-		}
-		// Send numQueries to RowNum.
-		results.RowNum = query.NumQueries
-
-		// 5. publish result to pulsar
-		//fmt.Println(results.Entities.Ids)
-		//fmt.Println(results.Distances)
-		node.PublishSearchResult(&results)
-	}
-
-	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+	node.Collections = tmpCollections
 }
--- a/internal/reader/query_node_time.go
+++ b/internal/reader/query_node_time.go
@ -4,13 +4,13 @@ type QueryNodeTime struct {
 	ReadTimeSyncMin uint64
 	ReadTimeSyncMax uint64
 	WriteTimeSync   uint64
-	ServiceTimeSync  uint64
+	ServiceTimeSync uint64
 	TSOTimeSync     uint64
 }

 type TimeRange struct {
-	timestampMin		uint64
-	timestampMax		uint64
+	timestampMin uint64
+	timestampMax uint64
 }

 func (t *QueryNodeTime) UpdateReadTimeSync() {
--- a/internal/reader/query_node_time_test.go
+++ b/internal/reader/query_node_time_test.go
@ -0,0 +1,46 @@
+package reader
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestQueryNodeTime_UpdateReadTimeSync(t *testing.T) {
+	queryNodeTimeSync := &QueryNodeTime{
+		ReadTimeSyncMin: uint64(0),
+		ReadTimeSyncMax: uint64(1),
+		WriteTimeSync:   uint64(2),
+		ServiceTimeSync: uint64(3),
+		TSOTimeSync:     uint64(4),
+	}
+
+	queryNodeTimeSync.UpdateReadTimeSync()
+
+	assert.Equal(t, queryNodeTimeSync.ReadTimeSyncMin, uint64(1))
+}
+
+func TestQueryNodeTime_UpdateSearchTimeSync(t *testing.T) {
+	queryNodeTimeSync := &QueryNodeTime{
+		ReadTimeSyncMin: uint64(0),
+		ReadTimeSyncMax: uint64(1),
+		WriteTimeSync:   uint64(2),
+		ServiceTimeSync: uint64(3),
+		TSOTimeSync:     uint64(4),
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: 1,
+	}
+	queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+
+	assert.Equal(t, queryNodeTimeSync.ServiceTimeSync, uint64(1))
+}
+
+func TestQueryNodeTime_UpdateTSOTimeSync(t *testing.T) {
+	// TODO: add UpdateTSOTimeSync test
+}
+
+func TestQueryNodeTime_UpdateWriteTimeSync(t *testing.T) {
+	// TODO: add UpdateWriteTimeSync test
+}
--- a/internal/reader/quety_node_test.go
+++ b/internal/reader/quety_node_test.go
@ -1,12 +1,78 @@
 package reader

 import (
+	"context"
+	"github.com/stretchr/testify/assert"
+	"github.com/zilliztech/milvus-distributed/internal/conf"
 	"testing"
 )

-// TODO: add query node test
-
-func TestQueryNode_RunInsertDelete(t *testing.T) {
+func TestQueryNode_CreateQueryNode(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())

+	node := CreateQueryNode(ctx, 0, 0, nil)
+	assert.NotNil(t, node)
 }

+func TestQueryNode_NewQueryNode(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())
+
+	node := NewQueryNode(ctx, 0, 0)
+	assert.NotNil(t, node)
+}
+
+func TestQueryNode_Close(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())
+
+	node := CreateQueryNode(ctx, 0, 0, nil)
+	assert.NotNil(t, node)
+
+	node.Close()
+}
+
+func TestQueryNode_QueryNodeDataInit(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())
+
+	node := CreateQueryNode(ctx, 0, 0, nil)
+	assert.NotNil(t, node)
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+}
+
+func TestQueryNode_NewCollection(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())
+
+	node := CreateQueryNode(ctx, 0, 0, nil)
+	assert.NotNil(t, node)
+
+	var collection = node.NewCollection(0, "collection0", "")
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, len(node.Collections), 1)
+}
+
+func TestQueryNode_DeleteCollection(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+	ctx, _ := context.WithCancel(context.Background())
+
+	node := CreateQueryNode(ctx, 0, 0, nil)
+	assert.NotNil(t, node)
+
+	var collection = node.NewCollection(0, "collection0", "")
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, len(node.Collections), 1)
+
+	node.DeleteCollection(collection)
+
+	assert.Equal(t, len(node.Collections), 0)
+}
--- a/internal/reader/reader.go
+++ b/internal/reader/reader.go
@ -2,6 +2,8 @@ package reader

 import (
 	"context"
+	"fmt"
+	"github.com/stretchr/testify/assert"
 	"github.com/zilliztech/milvus-distributed/internal/msgclient"
 	"log"
 	"sync"
@ -15,7 +17,6 @@ func StartQueryNode(ctx context.Context, pulsarURL string) {
 	qn := CreateQueryNode(ctx, 0, 0, &mc)

 	// Segments Services
-	go qn.SegmentManagementService()
 	go qn.SegmentStatisticService()

 	wg := sync.WaitGroup{}
@ -33,3 +34,99 @@ func StartQueryNode(ctx context.Context, pulsarURL string) {
 	wg.Wait()
 	qn.Close()
 }
+
+func (node *QueryNode) RunInsertDelete(wg *sync.WaitGroup) {
+	const Debug = true
+	const CountInsertMsgBaseline = 1000 * 1000
+	var BaselineCounter int64 = 0
+
+	if Debug {
+		for {
+			select {
+			case <-node.ctx.Done():
+				wg.Done()
+				return
+			default:
+				var msgLen = node.PrepareBatchMsg()
+				var timeRange = TimeRange{node.messageClient.TimeSyncStart(), node.messageClient.TimeSyncEnd()}
+				assert.NotEqual(nil, 0, timeRange.timestampMin)
+				assert.NotEqual(nil, 0, timeRange.timestampMax)
+
+				if node.msgCounter.InsertCounter/CountInsertMsgBaseline != BaselineCounter {
+					node.WriteQueryLog()
+					BaselineCounter = node.msgCounter.InsertCounter / CountInsertMsgBaseline
+				}
+
+				if msgLen[0] == 0 && len(node.buffer.InsertDeleteBuffer) <= 0 {
+					node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+					continue
+				}
+
+				node.QueryNodeDataInit()
+				node.MessagesPreprocess(node.messageClient.InsertOrDeleteMsg, timeRange)
+				//fmt.Println("MessagesPreprocess Done")
+				node.WriterDelete()
+				node.PreInsertAndDelete()
+				//fmt.Println("PreInsertAndDelete Done")
+				node.DoInsertAndDelete()
+				//fmt.Println("DoInsertAndDelete Done")
+				node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+			}
+		}
+	} else {
+		for {
+			select {
+			case <-node.ctx.Done():
+				wg.Done()
+				return
+			default:
+				var msgLen = node.PrepareBatchMsg()
+				var timeRange = TimeRange{node.messageClient.TimeSyncStart(), node.messageClient.TimeSyncEnd()}
+				assert.NotEqual(nil, 0, timeRange.timestampMin)
+				assert.NotEqual(nil, 0, timeRange.timestampMax)
+
+				if msgLen[0] == 0 && len(node.buffer.InsertDeleteBuffer) <= 0 {
+					node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+					continue
+				}
+
+				node.QueryNodeDataInit()
+				node.MessagesPreprocess(node.messageClient.InsertOrDeleteMsg, timeRange)
+				//fmt.Println("MessagesPreprocess Done")
+				node.WriterDelete()
+				node.PreInsertAndDelete()
+				//fmt.Println("PreInsertAndDelete Done")
+				node.DoInsertAndDelete()
+				//fmt.Println("DoInsertAndDelete Done")
+				node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+			}
+		}
+	}
+	wg.Done()
+}
+
+func (node *QueryNode) RunSearch(wg *sync.WaitGroup) {
+	for {
+		select {
+		case <-node.ctx.Done():
+			wg.Done()
+			return
+		case msg := <-node.messageClient.GetSearchChan():
+			node.messageClient.SearchMsg = node.messageClient.SearchMsg[:0]
+			node.messageClient.SearchMsg = append(node.messageClient.SearchMsg, msg)
+			//for  {
+			//if node.messageClient.SearchMsg[0].Timestamp < node.queryNodeTimeSync.ServiceTimeSync {
+			var status = node.Search(node.messageClient.SearchMsg)
+			fmt.Println("Do Search done")
+			if status.ErrorCode != 0 {
+				fmt.Println("Search Failed")
+				node.PublishFailedSearchResult()
+			}
+			//break
+			//}
+			//}
+		default:
+		}
+	}
+	wg.Done()
+}
--- a/internal/reader/reader_test.go
+++ b/internal/reader/reader_test.go
@ -2,15 +2,18 @@ package reader

 import (
 	"context"
+	"github.com/stretchr/testify/assert"
 	"github.com/zilliztech/milvus-distributed/internal/conf"
+	"github.com/zilliztech/milvus-distributed/internal/msgclient"
 	"strconv"
+	"sync"
 	"testing"
 	"time"
 )

 const ctxTimeInMillisecond = 10

-// NOTE: start pulsar before test
+// NOTE: start pulsar and etcd before test
 func TestReader_startQueryNode(t *testing.T) {
 	conf.LoadConfig("config.yaml")

@ -21,5 +24,69 @@ func TestReader_startQueryNode(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+
 	StartQueryNode(ctx, pulsarAddr)
+
+	// To make sure to get here
+	assert.Equal(t, 0, 0)
+}
+
+// NOTE: start pulsar before test
+func TestReader_RunInsertDelete(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+
+	mc.InitClient(ctx, pulsarAddr)
+	mc.ReceiveMessage()
+
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	wg := sync.WaitGroup{}
+
+	wg.Add(1)
+	go node.RunInsertDelete(&wg)
+	wg.Wait()
+
+	node.Close()
+
+	// To make sure to get here
+	assert.Equal(t, 0, 0)
+}
+
+// NOTE: start pulsar before test
+func TestReader_RunSearch(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+	ctx, _ := context.WithDeadline(context.Background(), d)
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+
+	mc.InitClient(ctx, pulsarAddr)
+	mc.ReceiveMessage()
+
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	wg := sync.WaitGroup{}
+
+	wg.Add(1)
+	go node.RunSearch(&wg)
+	wg.Wait()
+
+	node.Close()
+
+	// To make sure to get here
+	assert.Equal(t, 0, 0)
 }
--- a/internal/reader/result_test.go
+++ b/internal/reader/result_test.go
@ -2,6 +2,7 @@ package reader

 import (
 	"context"
+	"github.com/stretchr/testify/assert"
 	"github.com/zilliztech/milvus-distributed/internal/conf"
 	"github.com/zilliztech/milvus-distributed/internal/msgclient"
 	"strconv"
@ -24,8 +25,8 @@ func TestResult_PublishSearchResult(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	// Construct node, collection, partition and segment
@ -46,7 +47,10 @@ func TestResult_PublishSearchResult(t *testing.T) {
 		result.Entities.Ids = append(result.Entities.Ids, int64(i))
 		result.Distances = append(result.Distances, float32(i))
 	}
-	node.PublishSearchResult(&result)
+
+	status := node.PublishSearchResult(&result)
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
 	node.Close()
 }

@ -62,8 +66,8 @@ func TestResult_PublishFailedSearchResult(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	// Construct node, collection, partition and segment
@ -72,8 +76,8 @@ func TestResult_PublishFailedSearchResult(t *testing.T) {
 	var segment = partition.NewSegment(0)
 	node.SegmentsMap[0] = segment

-	// TODO: start pulsar server
-	node.PublishFailedSearchResult()
+	status := node.PublishFailedSearchResult()
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)

 	node.Close()
 }
@ -90,8 +94,8 @@ func TestResult_PublicStatistic(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	// Construct node, collection, partition and segment
@ -113,8 +117,8 @@ func TestResult_PublicStatistic(t *testing.T) {
 		statisticData = append(statisticData, stat)
 	}

-	// TODO: start pulsar server
-	node.PublicStatistic(&statisticData)
+	status := node.PublicStatistic(&statisticData)
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)

 	node.Close()
 }
--- a/internal/reader/search.go
+++ b/internal/reader/search.go
@ -0,0 +1,119 @@
+package reader
+
+import (
+	"fmt"
+	"github.com/zilliztech/milvus-distributed/internal/conf"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"sort"
+)
+
+func (node *QueryNode) Search(searchMessages []*msgPb.SearchMsg) msgPb.Status {
+
+	type SearchResultTmp struct {
+		ResultId       int64
+		ResultDistance float32
+	}
+
+	node.msgCounter.SearchCounter += int64(len(searchMessages))
+
+	// Traverse all messages in the current messageClient.
+	// TODO: Do not receive batched search requests
+	for _, msg := range searchMessages {
+		var clientId = msg.ClientId
+		var searchTimestamp = msg.Timestamp
+
+		// ServiceTimeSync update by TimeSync, which is get from proxy.
+		// Proxy send this timestamp per `conf.Config.Timesync.Interval` milliseconds.
+		// However, timestamp of search request (searchTimestamp) is precision time.
+		// So the ServiceTimeSync is always less than searchTimestamp.
+		// Here, we manually make searchTimestamp's logic time minus `conf.Config.Timesync.Interval` milliseconds.
+		// Which means `searchTimestamp.logicTime = searchTimestamp.logicTime - conf.Config.Timesync.Interval`.
+		var logicTimestamp = searchTimestamp << 46 >> 46
+		searchTimestamp = (searchTimestamp>>18-uint64(conf.Config.Timesync.Interval+600))<<18 + logicTimestamp
+
+		var vector = msg.Records
+		// We now only the first Json is valid.
+		var queryJson = msg.Json[0]
+
+		// 1. Timestamp check
+		// TODO: return or wait? Or adding graceful time
+		if searchTimestamp > node.queryNodeTimeSync.ServiceTimeSync {
+			fmt.Println("Invalid query time, timestamp = ", searchTimestamp>>18, ", SearchTimeSync = ", node.queryNodeTimeSync.ServiceTimeSync>>18)
+			return msgPb.Status{ErrorCode: 1}
+		}
+
+		// 2. Get query information from query json
+		query := node.QueryJson2Info(&queryJson)
+		// 2d slice for receiving multiple queries's results
+		var resultsTmp = make([][]SearchResultTmp, query.NumQueries)
+		for i := 0; i < int(query.NumQueries); i++ {
+			resultsTmp[i] = make([]SearchResultTmp, 0)
+		}
+
+		// 3. Do search in all segments
+		for _, segment := range node.SegmentsMap {
+			if segment.GetRowCount() <= 0 {
+				// Skip empty segment
+				continue
+			}
+
+			//fmt.Println("Search in segment:", segment.SegmentId, ",segment rows:", segment.GetRowCount())
+			var res, err = segment.SegmentSearch(query, searchTimestamp, vector)
+			if err != nil {
+				fmt.Println(err.Error())
+				return msgPb.Status{ErrorCode: 1}
+			}
+
+			for i := 0; i < int(query.NumQueries); i++ {
+				for j := i * query.TopK; j < (i+1)*query.TopK; j++ {
+					resultsTmp[i] = append(resultsTmp[i], SearchResultTmp{
+						ResultId:       res.ResultIds[j],
+						ResultDistance: res.ResultDistances[j],
+					})
+				}
+			}
+		}
+
+		// 4. Reduce results
+		for _, rTmp := range resultsTmp {
+			sort.Slice(rTmp, func(i, j int) bool {
+				return rTmp[i].ResultDistance < rTmp[j].ResultDistance
+			})
+		}
+
+		for _, rTmp := range resultsTmp {
+			if len(rTmp) > query.TopK {
+				rTmp = rTmp[:query.TopK]
+			}
+		}
+
+		var entities = msgPb.Entities{
+			Ids: make([]int64, 0),
+		}
+		var results = msgPb.QueryResult{
+			Status: &msgPb.Status{
+				ErrorCode: 0,
+			},
+			Entities:  &entities,
+			Distances: make([]float32, 0),
+			QueryId:   uint64(msg.Uid),
+			ProxyId:   clientId,
+		}
+		for _, rTmp := range resultsTmp {
+			for _, res := range rTmp {
+				results.Entities.Ids = append(results.Entities.Ids, res.ResultId)
+				results.Distances = append(results.Distances, res.ResultDistance)
+				results.Scores = append(results.Distances, float32(0))
+			}
+		}
+		// Send numQueries to RowNum.
+		results.RowNum = query.NumQueries
+
+		// 5. publish result to pulsar
+		//fmt.Println(results.Entities.Ids)
+		//fmt.Println(results.Distances)
+		node.PublishSearchResult(&results)
+	}
+
+	return msgPb.Status{ErrorCode: msgPb.ErrorCode_SUCCESS}
+}
--- a/internal/reader/search_test.go
+++ b/internal/reader/search_test.go
@ -0,0 +1,138 @@
+package reader
+
+import (
+	"context"
+	"encoding/binary"
+	"github.com/stretchr/testify/assert"
+	"github.com/zilliztech/milvus-distributed/internal/conf"
+	"github.com/zilliztech/milvus-distributed/internal/msgclient"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
+	"math"
+	"strconv"
+	"sync"
+	"testing"
+)
+
+// NOTE: start pulsar before test
+func TestSearch_Search(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	ctx, _ := context.WithCancel(context.Background())
+
+	mc := msgclient.ReaderMessageClient{}
+
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+
+	mc.InitClient(ctx, pulsarAddr)
+	mc.ReceiveMessage()
+
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	var collection = node.NewCollection(0, "collection0", "")
+	_ = collection.NewPartition("partition0")
+
+	const msgLength = 10
+	const DIM = 16
+	const N = 3
+
+	var vec = [DIM]float32{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	var rawData []byte
+	for _, ele := range vec {
+		buf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(buf, math.Float32bits(ele))
+		rawData = append(rawData, buf...)
+	}
+	bs := make([]byte, 4)
+	binary.LittleEndian.PutUint32(bs, 1)
+	rawData = append(rawData, bs...)
+	var records [][]byte
+	for i := 0; i < N; i++ {
+		records = append(records, rawData)
+	}
+
+	insertDeleteMessages := make([]*msgPb.InsertOrDeleteMsg, 0)
+
+	for i := 0; i < msgLength; i++ {
+		msg := msgPb.InsertOrDeleteMsg{
+			CollectionName: "collection0",
+			RowsData: &msgPb.RowData{
+				Blob: rawData,
+			},
+			Uid:          int64(i),
+			PartitionTag: "partition0",
+			Timestamp:    uint64(i + 1000),
+			SegmentId:    int64(i),
+			ChannelId:    0,
+			Op:           msgPb.OpType_INSERT,
+			ClientId:     0,
+			ExtraParams:  nil,
+		}
+		insertDeleteMessages = append(insertDeleteMessages, &msg)
+	}
+
+	timeRange := TimeRange{
+		timestampMin: 0,
+		timestampMax: math.MaxUint64,
+	}
+
+	node.QueryNodeDataInit()
+
+	assert.NotNil(t, node.deletePreprocessData)
+	assert.NotNil(t, node.insertData)
+	assert.NotNil(t, node.deleteData)
+
+	node.MessagesPreprocess(insertDeleteMessages, timeRange)
+
+	assert.Equal(t, len(node.insertData.insertIDs), msgLength)
+	assert.Equal(t, len(node.insertData.insertTimestamps), msgLength)
+	assert.Equal(t, len(node.insertData.insertRecords), msgLength)
+	assert.Equal(t, len(node.insertData.insertOffset), 0)
+
+	assert.Equal(t, len(node.buffer.InsertDeleteBuffer), 0)
+	assert.Equal(t, len(node.buffer.validInsertDeleteBuffer), 0)
+
+	assert.Equal(t, len(node.SegmentsMap), 10)
+	assert.Equal(t, len(node.Collections[0].Partitions[0].Segments), 10)
+
+	node.PreInsertAndDelete()
+
+	assert.Equal(t, len(node.insertData.insertOffset), msgLength)
+
+	wg := sync.WaitGroup{}
+	for segmentID := range node.insertData.insertRecords {
+		wg.Add(1)
+		go node.DoInsert(segmentID, &wg)
+	}
+	wg.Wait()
+
+	var queryRawData = make([]float32, 0)
+	for i := 0; i < DIM; i++ {
+		queryRawData = append(queryRawData, float32(i))
+	}
+
+	var queryJson = "{\"field_name\":\"fakevec\",\"num_queries\":1,\"topK\":10}"
+	searchMsg1 := msgPb.SearchMsg{
+		CollectionName: "collection0",
+		Records: &msgPb.VectorRowRecord{
+			FloatData: queryRawData,
+		},
+		PartitionTag: []string{"partition0"},
+		Uid:          int64(0),
+		Timestamp:    uint64(0),
+		ClientId:     int64(0),
+		ExtraParams:  nil,
+		Json:         []string{queryJson},
+	}
+	searchMessages := []*msgPb.SearchMsg{&searchMsg1}
+
+	node.queryNodeTimeSync.UpdateSearchTimeSync(timeRange)
+	assert.Equal(t, node.queryNodeTimeSync.ServiceTimeSync, timeRange.timestampMax)
+
+	status := node.Search(searchMessages)
+	assert.Equal(t, status.ErrorCode, msgPb.ErrorCode_SUCCESS)
+
+	node.Close()
+}
--- a/internal/reader/segment.go
+++ b/internal/reader/segment.go
@ -13,10 +13,9 @@ package reader
 */
 import "C"
 import (
-	"fmt"
+	"github.com/stretchr/testify/assert"
 	"github.com/zilliztech/milvus-distributed/internal/errors"
 	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
-	"github.com/stretchr/testify/assert"
 	"strconv"
 	"unsafe"
 )
@ -24,10 +23,10 @@ import (
 const SegmentLifetime = 20000

 const (
-	SegmentOpened  = 0
-	SegmentClosed  = 1
-	SegmentIndexing = 2
-	SegmentIndexed = 3
+//SegmentOpened  = 0
+//SegmentClosed  = 1
+//SegmentIndexing = 2
+//SegmentIndexed = 3
 )

 type Segment struct {
@ -38,23 +37,23 @@ type Segment struct {
 	SegmentStatus    int
 }

-func (s *Segment) GetStatus() int {
-	/*
-	bool
-	IsOpened(CSegmentBase c_segment);
-	*/
-	var isOpened = C.IsOpened(s.SegmentPtr)
-	if isOpened {
-		return SegmentOpened
-	} else {
-		return SegmentClosed
-	}
-}
+//func (s *Segment) GetStatus() int {
+//	/*
+//	bool
+//	IsOpened(CSegmentBase c_segment);
+//	*/
+//	var isOpened = C.IsOpened(s.SegmentPtr)
+//	if isOpened {
+//		return SegmentOpened
+//	} else {
+//		return SegmentClosed
+//	}
+//}

 func (s *Segment) GetRowCount() int64 {
 	/*
-	long int
-	GetRowCount(CSegmentBase c_segment);
+		long int
+		GetRowCount(CSegmentBase c_segment);
 	*/
 	var rowCount = C.GetRowCount(s.SegmentPtr)
 	return int64(rowCount)
@ -62,45 +61,45 @@ func (s *Segment) GetRowCount() int64 {

 func (s *Segment) GetDeletedCount() int64 {
 	/*
-	long int
-	GetDeletedCount(CSegmentBase c_segment);
+		long int
+		GetDeletedCount(CSegmentBase c_segment);
 	*/
 	var deletedCount = C.GetDeletedCount(s.SegmentPtr)
 	return int64(deletedCount)
 }

-func (s *Segment) CloseSegment(collection* Collection) error {
-	/*
-	int
-	Close(CSegmentBase c_segment);
-	*/
-	fmt.Println("Closing segment :", s.SegmentId)
-
-	var status = C.Close(s.SegmentPtr)
-	s.SegmentStatus = SegmentClosed
-
-	if status != 0 {
-		return errors.New("Close segment failed, error code = " + strconv.Itoa(int(status)))
-	}
-
-	// Build index after closing segment
-	//s.SegmentStatus = SegmentIndexing
-	//fmt.Println("Building index...")
-	//s.buildIndex(collection)
-
-	// TODO: remove redundant segment indexed status
-	// Change segment status to indexed
-	//s.SegmentStatus = SegmentIndexed
-	//fmt.Println("Segment closed and indexed")
-
-	fmt.Println("Segment closed")
-	return nil
-}
+//func (s *Segment) CloseSegment(collection* Collection) error {
+//	/*
+//	int
+//	Close(CSegmentBase c_segment);
+//	*/
+//	fmt.Println("Closing segment :", s.SegmentId)
+//
+//	var status = C.Close(s.SegmentPtr)
+//	s.SegmentStatus = SegmentClosed
+//
+//	if status != 0 {
+//		return errors.New("Close segment failed, error code = " + strconv.Itoa(int(status)))
+//	}
+//
+//	// Build index after closing segment
+//	//s.SegmentStatus = SegmentIndexing
+//	//fmt.Println("Building index...")
+//	//s.BuildIndex(collection)
+//
+//	// TODO: remove redundant segment indexed status
+//	// Change segment status to indexed
+//	//s.SegmentStatus = SegmentIndexed
+//	//fmt.Println("Segment closed and indexed")
+//
+//	fmt.Println("Segment closed")
+//	return nil
+//}

 func (s *Segment) GetMemSize() uint64 {
 	/*
-	long int
-	GetMemoryUsageInBytes(CSegmentBase c_segment);
+		long int
+		GetMemoryUsageInBytes(CSegmentBase c_segment);
 	*/
 	var memoryUsageInBytes = C.GetMemoryUsageInBytes(s.SegmentPtr)

@ -110,8 +109,8 @@ func (s *Segment) GetMemSize() uint64 {
 ////////////////////////////////////////////////////////////////////////////
 func (s *Segment) SegmentPreInsert(numOfRecords int) int64 {
 	/*
-	long int
-	PreInsert(CSegmentBase c_segment, long int size);
+		long int
+		PreInsert(CSegmentBase c_segment, long int size);
 	*/
 	var offset = C.PreInsert(s.SegmentPtr, C.long(int64(numOfRecords)))

@ -120,8 +119,8 @@ func (s *Segment) SegmentPreInsert(numOfRecords int) int64 {

 func (s *Segment) SegmentPreDelete(numOfRecords int) int64 {
 	/*
-	long int
-	PreDelete(CSegmentBase c_segment, long int size);
+		long int
+		PreDelete(CSegmentBase c_segment, long int size);
 	*/
 	var offset = C.PreDelete(s.SegmentPtr, C.long(int64(numOfRecords)))

@ -130,15 +129,15 @@ func (s *Segment) SegmentPreDelete(numOfRecords int) int64 {

 func (s *Segment) SegmentInsert(offset int64, entityIDs *[]int64, timestamps *[]uint64, records *[][]byte) error {
 	/*
-	int
-	Insert(CSegmentBase c_segment,
-	           long int reserved_offset,
-	           signed long int size,
-	           const long* primary_keys,
-	           const unsigned long* timestamps,
-	           void* raw_data,
-	           int sizeof_per_row,
-	           signed long int count);
+		int
+		Insert(CSegmentBase c_segment,
+		           long int reserved_offset,
+		           signed long int size,
+		           const long* primary_keys,
+		           const unsigned long* timestamps,
+		           void* raw_data,
+		           int sizeof_per_row,
+		           signed long int count);
 	*/
 	// Blobs to one big blob
 	var numOfRow = len(*entityIDs)
@ -146,7 +145,7 @@ func (s *Segment) SegmentInsert(offset int64, entityIDs *[]int64, timestamps *[]

 	assert.Equal(nil, numOfRow, len(*records))

-	var rawData = make([]byte, numOfRow * sizeofPerRow)
+	var rawData = make([]byte, numOfRow*sizeofPerRow)
 	var copyOffset = 0
 	for i := 0; i < len(*records); i++ {
 		copy(rawData[copyOffset:], (*records)[i])
@ -178,12 +177,12 @@ func (s *Segment) SegmentInsert(offset int64, entityIDs *[]int64, timestamps *[]

 func (s *Segment) SegmentDelete(offset int64, entityIDs *[]int64, timestamps *[]uint64) error {
 	/*
-	int
-	Delete(CSegmentBase c_segment,
-	           long int reserved_offset,
-	           long size,
-	           const long* primary_keys,
-	           const unsigned long* timestamps);
+		int
+		Delete(CSegmentBase c_segment,
+		           long int reserved_offset,
+		           long size,
+		           const long* primary_keys,
+		           const unsigned long* timestamps);
 	*/
 	var cOffset = C.long(offset)
 	var cSize = C.long(len(*entityIDs))
@ -201,14 +200,14 @@ func (s *Segment) SegmentDelete(offset int64, entityIDs *[]int64, timestamps *[]

 func (s *Segment) SegmentSearch(query *QueryInfo, timestamp uint64, vectorRecord *msgPb.VectorRowRecord) (*SearchResult, error) {
 	/*
-	int
-	Search(CSegmentBase c_segment,
-	       CQueryInfo  c_query_info,
-	       unsigned long timestamp,
-	       float* query_raw_data,
-	       int num_of_query_raw_data,
-	       long int* result_ids,
-	       float* result_distances);
+		int
+		Search(CSegmentBase c_segment,
+		       CQueryInfo  c_query_info,
+		       unsigned long timestamp,
+		       float* query_raw_data,
+		       int num_of_query_raw_data,
+		       long int* result_ids,
+		       float* result_distances);
 	*/
 	//type CQueryInfo C.CQueryInfo

@ -218,8 +217,8 @@ func (s *Segment) SegmentSearch(query *QueryInfo, timestamp uint64, vectorRecord
 		field_name:  C.CString(query.FieldName),
 	}

-	resultIds := make([]int64, int64(query.TopK) * query.NumQueries)
-	resultDistances := make([]float32, int64(query.TopK) * query.NumQueries)
+	resultIds := make([]int64, int64(query.TopK)*query.NumQueries)
+	resultDistances := make([]float32, int64(query.TopK)*query.NumQueries)

 	var cTimestamp = C.ulong(timestamp)
 	var cResultIds = (*C.long)(&resultIds[0])
--- a/internal/reader/segment_service.go
+++ b/internal/reader/segment_service.go
@ -9,61 +9,45 @@ import (
 	"time"
 )

-func (node *QueryNode) SegmentsManagement() {
-	//node.queryNodeTimeSync.UpdateTSOTimeSync()
-	//var timeNow = node.queryNodeTimeSync.TSOTimeSync
+//func (node *QueryNode) SegmentsManagement() {
+//	//node.queryNodeTimeSync.UpdateTSOTimeSync()
+//	//var timeNow = node.queryNodeTimeSync.TSOTimeSync
+//
+//	timeNow := node.messageClient.GetTimeNow() >> 18
+//
+//	for _, collection := range node.Collections {
+//		for _, partition := range collection.Partitions {
+//			for _, segment := range partition.Segments {
+//				if segment.SegmentStatus != SegmentOpened {
+//					continue
+//				}
+//
+//				// fmt.Println("timeNow = ", timeNow, "SegmentCloseTime = ", segment.SegmentCloseTime)
+//				if timeNow >= segment.SegmentCloseTime {
+//					go segment.CloseSegment(collection)
+//				}
+//			}
+//		}
+//	}
+//}

-	timeNow := node.messageClient.GetTimeNow() >> 18
-
-	for _, collection := range node.Collections {
-		for _, partition := range collection.Partitions {
-			for _, segment := range partition.Segments {
-				if segment.SegmentStatus != SegmentOpened {
-					continue
-				}
-
-				// fmt.Println("timeNow = ", timeNow, "SegmentCloseTime = ", segment.SegmentCloseTime)
-				if timeNow >= segment.SegmentCloseTime {
-					go segment.CloseSegment(collection)
-				}
-			}
-		}
-	}
-}
-
-func (node *QueryNode) SegmentManagementService() {
-	sleepMillisecondTime := 1000
-	fmt.Println("do segments management in ", strconv.Itoa(sleepMillisecondTime), "ms")
-	for {
-		select {
-		case <-node.ctx.Done():
-			return
-		default:
-			time.Sleep(time.Duration(sleepMillisecondTime) * time.Millisecond)
-			node.SegmentsManagement()
-		}
-	}
-}
+//func (node *QueryNode) SegmentManagementService() {
+//	sleepMillisecondTime := 1000
+//	fmt.Println("do segments management in ", strconv.Itoa(sleepMillisecondTime), "ms")
+//	for {
+//		select {
+//		case <-node.ctx.Done():
+//			return
+//		default:
+//			time.Sleep(time.Duration(sleepMillisecondTime) * time.Millisecond)
+//			node.SegmentsManagement()
+//		}
+//	}
+//}

 func (node *QueryNode) SegmentStatistic(sleepMillisecondTime int) {
 	var statisticData = make([]masterPb.SegmentStat, 0)

-	//for _, collection := range node.Collections {
-	//	for _, partition := range collection.Partitions {
-	//		for _, openedSegment := range partition.OpenedSegments {
-	//			currentMemSize := openedSegment.GetMemSize()
-	//			memIncreaseRate := float32((int64(currentMemSize))-(int64(openedSegment.LastMemSize))) / (float32(sleepMillisecondTime) / 1000)
-	//			stat := masterPb.SegmentStat{
-	//				// TODO: set master pb's segment id type from uint64 to int64
-	//				SegmentId:  uint64(openedSegment.SegmentId),
-	//				MemorySize: currentMemSize,
-	//				MemoryRate: memIncreaseRate,
-	//			}
-	//			statisticData = append(statisticData, stat)
-	//		}
-	//	}
-	//}
-
 	for segmentID, segment := range node.SegmentsMap {
 		currentMemSize := segment.GetMemSize()
 		memIncreaseRate := float32((int64(currentMemSize))-(int64(segment.LastMemSize))) / (float32(sleepMillisecondTime) / 1000)
--- a/internal/reader/segment_service_test.go
+++ b/internal/reader/segment_service_test.go
@ -9,39 +9,40 @@ import (
 	"time"
 )

-func TestSegmentManagement_SegmentsManagement(t *testing.T) {
-	// Construct node, collection, partition and segment
-	ctx := context.Background()
-	node := NewQueryNode(ctx, 0, 0)
-	var collection = node.NewCollection(0, "collection0", "")
-	var partition = collection.NewPartition("partition0")
-	var segment = partition.NewSegment(0)
-	node.SegmentsMap[0] = segment
+//func TestSegmentManagement_SegmentsManagement(t *testing.T) {
+//	// Construct node, collection, partition and segment
+//	ctx := context.Background()
+//	node := NewQueryNode(ctx, 0, 0)
+//	var collection = node.NewCollection(0, "collection0", "")
+//	var partition = collection.NewPartition("partition0")
+//	var segment = partition.NewSegment(0)
+//	node.SegmentsMap[0] = segment
+//
+//	node.SegmentsManagement()
+//
+//	node.Close()
+//}

-	node.SegmentsManagement()
-
-	node.Close()
-}
-
-func TestSegmentManagement_SegmentService(t *testing.T) {
-	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
-	ctx, _ := context.WithDeadline(context.Background(), d)
-
-	// Construct node, collection, partition and segment
-	node := NewQueryNode(ctx, 0, 0)
-	var collection = node.NewCollection(0, "collection0", "")
-	var partition = collection.NewPartition("partition0")
-	var segment = partition.NewSegment(0)
-	node.SegmentsMap[0] = segment
-
-	node.SegmentManagementService()
-
-	node.Close()
-}
+//func TestSegmentManagement_SegmentService(t *testing.T) {
+//	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
+//	ctx, _ := context.WithDeadline(context.Background(), d)
+//
+//	// Construct node, collection, partition and segment
+//	node := NewQueryNode(ctx, 0, 0)
+//	var collection = node.NewCollection(0, "collection0", "")
+//	var partition = collection.NewPartition("partition0")
+//	var segment = partition.NewSegment(0)
+//	node.SegmentsMap[0] = segment
+//
+//	node.SegmentManagementService()
+//
+//	node.Close()
+//}

 // NOTE: start pulsar before test
 func TestSegmentManagement_SegmentStatistic(t *testing.T) {
 	conf.LoadConfig("config.yaml")
+
 	ctx, _ := context.WithCancel(context.Background())

 	mc := msgclient.ReaderMessageClient{}
@ -49,9 +50,10 @@ func TestSegmentManagement_SegmentStatistic(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	mc.ReceiveMessage()
+
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	// Construct node, collection, partition and segment
@ -68,6 +70,7 @@ func TestSegmentManagement_SegmentStatistic(t *testing.T) {
 // NOTE: start pulsar before test
 func TestSegmentManagement_SegmentStatisticService(t *testing.T) {
 	conf.LoadConfig("config.yaml")
+
 	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
 	ctx, _ := context.WithDeadline(context.Background(), d)

@ -76,9 +79,10 @@ func TestSegmentManagement_SegmentStatisticService(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	mc.ReceiveMessage()
+
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	// Construct node, collection, partition and segment
--- a/internal/reader/segment_test.go
+++ b/internal/reader/segment_test.go
@ -7,8 +7,8 @@ import (
 	"math"
 	"testing"

-	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
 	"github.com/stretchr/testify/assert"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
 )

 func TestSegment_ConstructorAndDestructor(t *testing.T) {
@ -19,11 +19,21 @@ func TestSegment_ConstructorAndDestructor(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -35,6 +45,13 @@ func TestSegment_SegmentInsert(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -68,10 +85,13 @@ func TestSegment_SegmentInsert(t *testing.T) {
 	assert.NoError(t, err)

 	// 6. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -83,6 +103,13 @@ func TestSegment_SegmentDelete(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -96,10 +123,13 @@ func TestSegment_SegmentDelete(t *testing.T) {
 	assert.NoError(t, err)

 	// 5. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -111,6 +141,13 @@ func TestSegment_SegmentSearch(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := make([]int64, 0)
 	timestamps := make([]uint64, 0)
@ -160,10 +197,13 @@ func TestSegment_SegmentSearch(t *testing.T) {
 	fmt.Println(searchRes)

 	// 7. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -175,15 +215,25 @@ func TestSegment_SegmentPreInsert(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Do PreInsert
 	var offset = segment.SegmentPreInsert(10)
 	assert.GreaterOrEqual(t, offset, int64(0))

 	// 3. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -195,59 +245,69 @@ func TestSegment_SegmentPreDelete(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Do PreDelete
 	var offset = segment.SegmentPreDelete(10)
 	assert.GreaterOrEqual(t, offset, int64(0))

 	// 3. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

 //  Segment util functions test
 ////////////////////////////////////////////////////////////////////////////
-func TestSegment_GetStatus(t *testing.T) {
-	ctx := context.Background()
-	// 1. Construct node, collection, partition and segment
-	node := NewQueryNode(ctx, 0, 0)
-	var collection = node.NewCollection(0, "collection0", "")
-	var partition = collection.NewPartition("partition0")
-	var segment = partition.NewSegment(0)
+//func TestSegment_GetStatus(t *testing.T) {
+//	ctx := context.Background()
+//	// 1. Construct node, collection, partition and segment
+//	node := NewQueryNode(ctx, 0, 0)
+//	var collection = node.NewCollection(0, "collection0", "")
+//	var partition = collection.NewPartition("partition0")
+//	var segment = partition.NewSegment(0)
+//
+//	// 2. Get segment status
+//	var status = segment.GetStatus()
+//	assert.Equal(t, status, SegmentOpened)
+//
+//	// 3. Destruct collection, partition and segment
+//	partition.DeleteSegment(segment)
+//	collection.DeletePartition(partition)
+//	node.DeleteCollection(collection)
+//
+//	node.Close()
+//}

-	// 2. Get segment status
-	var status = segment.GetStatus()
-	assert.Equal(t, status, SegmentOpened)
-
-	// 3. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
-	node.DeleteCollection(collection)
-
-	node.Close()
-}
-
-func TestSegment_Close(t *testing.T) {
-	ctx := context.Background()
-	// 1. Construct node, collection, partition and segment
-	node := NewQueryNode(ctx, 0, 0)
-	var collection = node.NewCollection(0, "collection0", "")
-	var partition = collection.NewPartition("partition0")
-	var segment = partition.NewSegment(0)
-
-	// 2. Close segment
-	var err = segment.CloseSegment(collection)
-	assert.NoError(t, err)
-
-	// 3. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
-	node.DeleteCollection(collection)
-
-	node.Close()
-}
+//func TestSegment_Close(t *testing.T) {
+//	ctx := context.Background()
+//	// 1. Construct node, collection, partition and segment
+//	node := NewQueryNode(ctx, 0, 0)
+//	var collection = node.NewCollection(0, "collection0", "")
+//	var partition = collection.NewPartition("partition0")
+//	var segment = partition.NewSegment(0)
+//
+//	// 2. Close segment
+//	var err = segment.CloseSegment(collection)
+//	assert.NoError(t, err)
+//
+//	// 3. Destruct collection, partition and segment
+//	partition.DeleteSegment(segment)
+//	collection.DeletePartition(partition)
+//	node.DeleteCollection(collection)
+//
+//	node.Close()
+//}

 func TestSegment_GetRowCount(t *testing.T) {
 	ctx := context.Background()
@ -257,6 +317,13 @@ func TestSegment_GetRowCount(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -294,10 +361,13 @@ func TestSegment_GetRowCount(t *testing.T) {
 	assert.Equal(t, rowCount, int64(len(ids)))

 	// 7. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -309,6 +379,13 @@ func TestSegment_GetDeletedCount(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -327,10 +404,13 @@ func TestSegment_GetDeletedCount(t *testing.T) {
 	assert.Equal(t, deletedCount, int64(0))

 	// 6. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -342,6 +422,13 @@ func TestSegment_GetMemSize(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -379,10 +466,13 @@ func TestSegment_GetMemSize(t *testing.T) {
 	assert.Equal(t, memSize, uint64(2785280))

 	// 7. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }

@ -402,6 +492,13 @@ func TestSegment_RealSchemaTest(t *testing.T) {
 	var partition = collection.NewPartition("partition0")
 	var segment = partition.NewSegment(0)

+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
 	// 2. Create ids and timestamps
 	ids := []int64{1, 2, 3}
 	timestamps := []uint64{0, 0, 0}
@ -435,9 +532,12 @@ func TestSegment_RealSchemaTest(t *testing.T) {
 	assert.NoError(t, err)

 	// 6. Destruct collection, partition and segment
-	partition.DeleteSegment(segment)
-	collection.DeletePartition(partition)
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
 	node.DeleteCollection(collection)

+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
 	node.Close()
 }
--- a/internal/reader/util_functions.go
+++ b/internal/reader/util_functions.go
@ -64,6 +64,16 @@ func (node *QueryNode) GetSegmentBySegmentID(segmentID int64) (*Segment, error)
 	return targetSegment, nil
 }

+func (node *QueryNode) FoundSegmentBySegmentID(segmentID int64) bool {
+	targetSegment := node.SegmentsMap[segmentID]
+
+	if targetSegment == nil {
+		return false
+	}
+
+	return true
+}
+
 func (c *Collection) GetPartitionByName(partitionName string) (partition *Partition) {
 	for _, partition := range c.Partitions {
 		if partition.PartitionName == partitionName {
@ -124,3 +134,21 @@ func (node *QueryNode) WriteQueryLog() {

 	fmt.Println("write log done")
 }
+
+func (node *QueryNode) PrepareBatchMsg() []int {
+	var msgLen = node.messageClient.PrepareBatchMsg()
+	return msgLen
+}
+
+func (node *QueryNode) QueryJson2Info(queryJson *string) *QueryInfo {
+	var query QueryInfo
+	var err = json.Unmarshal([]byte(*queryJson), &query)
+
+	if err != nil {
+		log.Fatal("Unmarshal query json failed")
+		return nil
+	}
+
+	//fmt.Println(query)
+	return &query
+}
--- a/internal/reader/util_functions_test.go
+++ b/internal/reader/util_functions_test.go
@ -4,6 +4,7 @@ import (
 	"context"
 	"github.com/zilliztech/milvus-distributed/internal/conf"
 	"github.com/zilliztech/milvus-distributed/internal/msgclient"
+	msgPb "github.com/zilliztech/milvus-distributed/internal/proto/message"
 	"strconv"
 	"testing"
 	"time"
@ -14,6 +15,7 @@ import (
 // NOTE: start pulsar before test
 func TestUtilFunctions_GetKey2Segments(t *testing.T) {
 	conf.LoadConfig("config.yaml")
+
 	d := time.Now().Add(ctxTimeInMillisecond * time.Millisecond)
 	ctx, _ := context.WithDeadline(context.Background(), d)

@ -22,13 +24,58 @@ func TestUtilFunctions_GetKey2Segments(t *testing.T) {
 	pulsarAddr += conf.Config.Pulsar.Address
 	pulsarAddr += ":"
 	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
-	mc.InitClient(ctx, pulsarAddr)

+	mc.InitClient(ctx, pulsarAddr)
 	mc.ReceiveMessage()
+
 	node := CreateQueryNode(ctx, 0, 0, &mc)

 	node.messageClient.PrepareKey2SegmentMsg()
-	var _, _, _ = node.GetKey2Segments()
+
+	const msgLength = 10
+
+	for i := 0; i < msgLength; i++ {
+		key2SegMsg := msgPb.Key2SegMsg{
+			Uid:       int64(i),
+			Timestamp: uint64(i + 1000),
+			SegmentId: []int64{int64(i)},
+		}
+		node.messageClient.Key2SegMsg = append(node.messageClient.Key2SegMsg, &key2SegMsg)
+	}
+
+	entityIDs, timestamps, segmentIDs := node.GetKey2Segments()
+
+	assert.Equal(t, len(*entityIDs), msgLength)
+	assert.Equal(t, len(*timestamps), msgLength)
+	assert.Equal(t, len(*segmentIDs), msgLength)
+
+	node.Close()
+}
+
+func TestUtilFunctions_GetCollectionByID(t *testing.T) {
+	ctx := context.Background()
+
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+	var segment = partition.NewSegment(0)
+
+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
+	c := node.GetCollectionByID(uint64(0))
+	assert.Equal(t, c.CollectionName, "collection0")
+
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
+	node.DeleteCollection(collection)
+
+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)

 	node.Close()
 }
@ -43,6 +90,7 @@ func TestUtilFunctions_GetCollectionByCollectionName(t *testing.T) {
 	var c0, err = node.GetCollectionByCollectionName("collection0")
 	assert.NoError(t, err)
 	assert.Equal(t, c0.CollectionName, "collection0")
+
 	c0 = node.GetCollectionByID(0)
 	assert.NotNil(t, c0)
 	assert.Equal(t, c0.CollectionID, uint64(0))
@ -52,6 +100,7 @@ func TestUtilFunctions_GetCollectionByCollectionName(t *testing.T) {

 func TestUtilFunctions_GetSegmentBySegmentID(t *testing.T) {
 	ctx := context.Background()
+
 	// 1. Construct node, collection, partition and segment
 	node := NewQueryNode(ctx, 0, 0)
 	var collection = node.NewCollection(0, "collection0", "")
@ -66,3 +115,85 @@ func TestUtilFunctions_GetSegmentBySegmentID(t *testing.T) {

 	node.Close()
 }
+
+func TestUtilFunctions_FoundSegmentBySegmentID(t *testing.T) {
+	ctx := context.Background()
+
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+	var segment = partition.NewSegment(0)
+
+	node.SegmentsMap[int64(0)] = segment
+
+	assert.Equal(t, collection.CollectionName, "collection0")
+	assert.Equal(t, partition.PartitionName, "partition0")
+	assert.Equal(t, segment.SegmentId, int64(0))
+	assert.Equal(t, len(node.SegmentsMap), 1)
+
+	b1 := node.FoundSegmentBySegmentID(int64(0))
+	assert.Equal(t, b1, true)
+
+	b2 := node.FoundSegmentBySegmentID(int64(1))
+	assert.Equal(t, b2, false)
+
+	partition.DeleteSegment(node, segment)
+	collection.DeletePartition(node, partition)
+	node.DeleteCollection(collection)
+
+	assert.Equal(t, len(node.Collections), 0)
+	assert.Equal(t, len(node.SegmentsMap), 0)
+
+	node.Close()
+}
+
+func TestUtilFunctions_GetPartitionByName(t *testing.T) {
+	ctx := context.Background()
+
+	node := NewQueryNode(ctx, 0, 0)
+	var collection = node.NewCollection(0, "collection0", "")
+	var partition = collection.NewPartition("partition0")
+
+	var p = collection.GetPartitionByName("partition0")
+	assert.Equal(t, p.PartitionName, "partition0")
+
+	collection.DeletePartition(node, partition)
+	node.DeleteCollection(collection)
+
+	node.Close()
+}
+
+// NOTE: start pulsar before test
+func TestUtilFunctions_PrepareBatchMsg(t *testing.T) {
+	conf.LoadConfig("config.yaml")
+
+	ctx, _ := context.WithCancel(context.Background())
+
+	mc := msgclient.ReaderMessageClient{}
+	pulsarAddr := "pulsar://"
+	pulsarAddr += conf.Config.Pulsar.Address
+	pulsarAddr += ":"
+	pulsarAddr += strconv.FormatInt(int64(conf.Config.Pulsar.Port), 10)
+
+	mc.InitClient(ctx, pulsarAddr)
+	mc.ReceiveMessage()
+
+	node := CreateQueryNode(ctx, 0, 0, &mc)
+
+	node.PrepareBatchMsg()
+	node.Close()
+}
+
+func TestUtilFunctions_QueryJson2Info(t *testing.T) {
+	ctx := context.Background()
+	node := NewQueryNode(ctx, 0, 0)
+
+	var queryJson = "{\"field_name\":\"age\",\"num_queries\":1,\"topK\":10}"
+	info := node.QueryJson2Info(&queryJson)
+
+	assert.Equal(t, info.FieldName, "age")
+	assert.Equal(t, info.NumQueries, int64(1))
+	assert.Equal(t, info.TopK, 10)
+
+	node.Close()
+}