diff --git a/internal/querynode/benchmark_test.go b/internal/querynode/benchmark_test.go
new file mode 100644
index 0000000000..c41d1290a0
--- /dev/null
+++ b/internal/querynode/benchmark_test.go
@@ -0,0 +1,210 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package querynode
+
+import (
+	"context"
+	"os"
+	"runtime/pprof"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.uber.org/zap/zapcore"
+
+	"github.com/milvus-io/milvus/internal/log"
+	msgstream2 "github.com/milvus-io/milvus/internal/mq/msgstream"
+	"github.com/milvus-io/milvus/internal/util/typeutil"
+)
+
+const (
+	maxNQ = 100
+	nb    = 10000
+)
+
+func benchmarkQueryCollectionSearch(nq int, b *testing.B) {
+	log.SetLevel(zapcore.ErrorLevel)
+	defer log.SetLevel(zapcore.DebugLevel)
+
+	tx, cancel := context.WithCancel(context.Background())
+
+	queryCollection, err := genSimpleQueryCollection(tx, cancel)
+	assert.NoError(b, err)
+
+	// search only one segment
+	err = queryCollection.streaming.replica.removeSegment(defaultSegmentID)
+	assert.NoError(b, err)
+	err = queryCollection.historical.replica.removeSegment(defaultSegmentID)
+	assert.NoError(b, err)
+
+	assert.Equal(b, 0, queryCollection.historical.replica.getSegmentNum())
+	assert.Equal(b, 0, queryCollection.streaming.replica.getSegmentNum())
+
+	segment, err := genSealedSegmentWithMsgLength(nb)
+	assert.NoError(b, err)
+	err = queryCollection.historical.replica.setSegment(segment)
+	assert.NoError(b, err)
+
+	sessionManager := NewSessionManager(withSessionCreator(mockProxyCreator()))
+	sessionManager.AddSession(&NodeInfo{
+		NodeID:  0,
+		Address: "",
+	})
+	queryCollection.sessionManager = sessionManager
+
+	// segment check
+	assert.Equal(b, 1, queryCollection.historical.replica.getSegmentNum())
+	assert.Equal(b, 0, queryCollection.streaming.replica.getSegmentNum())
+	seg, err := queryCollection.historical.replica.getSegmentByID(defaultSegmentID)
+	assert.NoError(b, err)
+	assert.Equal(b, int64(nb), seg.getRowCount())
+	sizePerRecord, err := typeutil.EstimateSizePerRecord(genSimpleSegCoreSchema())
+	assert.NoError(b, err)
+	expectSize := sizePerRecord * nb
+	assert.Equal(b, seg.getMemSize(), int64(expectSize))
+
+	// warming up
+	msgTmp, err := genSearchMsg(10)
+	assert.NoError(b, err)
+	for j := 0; j < 10000; j++ {
+		err = queryCollection.search(msgTmp)
+		assert.NoError(b, err)
+	}
+
+	msgs := make([]*msgstream2.SearchMsg, maxNQ/nq)
+	for i := 0; i < maxNQ/nq; i++ {
+		msg, err := genSearchMsg(nq)
+		assert.NoError(b, err)
+		msgs[i] = msg
+	}
+
+	f, err := os.Create("nq_" + strconv.Itoa(nq) + ".perf")
+	if err != nil {
+		panic(err)
+	}
+	if err = pprof.StartCPUProfile(f); err != nil {
+		panic(err)
+	}
+	defer pprof.StopCPUProfile()
+
+	// start benchmark
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		for j := 0; j < maxNQ/nq; j++ {
+			err = queryCollection.search(msgs[j])
+			assert.NoError(b, err)
+		}
+	}
+}
+
+func benchmarkQueryCollectionSearchIndex(nq int, indexType string, b *testing.B) {
+	log.SetLevel(zapcore.ErrorLevel)
+	defer log.SetLevel(zapcore.DebugLevel)
+
+	tx, cancel := context.WithCancel(context.Background())
+
+	queryCollection, err := genSimpleQueryCollection(tx, cancel)
+	assert.NoError(b, err)
+
+	err = queryCollection.historical.replica.removeSegment(defaultSegmentID)
+	assert.NoError(b, err)
+	err = queryCollection.streaming.replica.removeSegment(defaultSegmentID)
+	assert.NoError(b, err)
+
+	assert.Equal(b, 0, queryCollection.historical.replica.getSegmentNum())
+	assert.Equal(b, 0, queryCollection.streaming.replica.getSegmentNum())
+
+	node, err := genSimpleQueryNode(tx)
+	assert.NoError(b, err)
+	node.loader.historicalReplica = queryCollection.historical.replica
+
+	err = loadIndexForSegment(tx, node, defaultSegmentID, nb, indexType, L2)
+	assert.NoError(b, err)
+
+	sessionManager := NewSessionManager(withSessionCreator(mockProxyCreator()))
+	sessionManager.AddSession(&NodeInfo{
+		NodeID:  0,
+		Address: "",
+	})
+	queryCollection.sessionManager = sessionManager
+
+	// segment check
+	assert.Equal(b, 1, queryCollection.historical.replica.getSegmentNum())
+	assert.Equal(b, 0, queryCollection.streaming.replica.getSegmentNum())
+	seg, err := queryCollection.historical.replica.getSegmentByID(defaultSegmentID)
+	assert.NoError(b, err)
+	assert.Equal(b, int64(nb), seg.getRowCount())
+	sizePerRecord, err := typeutil.EstimateSizePerRecord(genSimpleSegCoreSchema())
+	assert.NoError(b, err)
+	expectSize := sizePerRecord * nb
+	assert.Equal(b, seg.getMemSize(), int64(expectSize))
+
+	// warming up
+	msgTmp, err := genSearchMsg(10)
+	assert.NoError(b, err)
+	for j := 0; j < 10000; j++ {
+		err = queryCollection.search(msgTmp)
+		assert.NoError(b, err)
+	}
+
+	msgs := make([]*msgstream2.SearchMsg, maxNQ/nq)
+	for i := 0; i < maxNQ/nq; i++ {
+		msg, err := genSearchMsg(nq)
+		assert.NoError(b, err)
+		msgs[i] = msg
+	}
+
+	f, err := os.Create(indexType + "_nq_" + strconv.Itoa(nq) + ".perf")
+	if err != nil {
+		panic(err)
+	}
+	if err = pprof.StartCPUProfile(f); err != nil {
+		panic(err)
+	}
+	defer pprof.StopCPUProfile()
+
+	// start benchmark
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		for j := 0; j < maxNQ/nq; j++ {
+			err = queryCollection.search(msgs[j])
+			assert.NoError(b, err)
+		}
+	}
+}
+
+func BenchmarkSearch_NQ1(b *testing.B)     { benchmarkQueryCollectionSearch(1, b) }
+func BenchmarkSearch_NQ10(b *testing.B)    { benchmarkQueryCollectionSearch(10, b) }
+func BenchmarkSearch_NQ100(b *testing.B)   { benchmarkQueryCollectionSearch(100, b) }
+func BenchmarkSearch_NQ1000(b *testing.B)  { benchmarkQueryCollectionSearch(1000, b) }
+func BenchmarkSearch_NQ10000(b *testing.B) { benchmarkQueryCollectionSearch(10000, b) }
+
+func BenchmarkSearch_IVFFLAT_NQ1(b *testing.B) {
+	benchmarkQueryCollectionSearchIndex(1, IndexFaissIVFFlat, b)
+}
+func BenchmarkSearch_IVFFLAT_NQ10(b *testing.B) {
+	benchmarkQueryCollectionSearchIndex(10, IndexFaissIVFFlat, b)
+}
+func BenchmarkSearch_IVFFLAT_NQ100(b *testing.B) {
+	benchmarkQueryCollectionSearchIndex(100, IndexFaissIVFFlat, b)
+}
+func BenchmarkSearch_IVFFLAT_NQ1000(b *testing.B) {
+	benchmarkQueryCollectionSearchIndex(1000, IndexFaissIVFFlat, b)
+}
+func BenchmarkSearch_IVFFLAT_NQ10000(b *testing.B) {
+	benchmarkQueryCollectionSearchIndex(10000, IndexFaissIVFFlat, b)
+}
diff --git a/internal/querynode/mock_test.go b/internal/querynode/mock_test.go
index 364a16c713..c7d4cbcfc6 100644
--- a/internal/querynode/mock_test.go
+++ b/internal/querynode/mock_test.go
@@ -19,6 +19,7 @@ package querynode
 import (
 	"context"
 	"errors"
+	"fmt"
 	"math"
 	"math/rand"
 	"strconv"
@@ -43,6 +44,7 @@ import (
 	"github.com/milvus-io/milvus/internal/storage"
 	"github.com/milvus-io/milvus/internal/util"
 	"github.com/milvus-io/milvus/internal/util/etcd"
+	"github.com/milvus-io/milvus/internal/util/funcutil"
 )
 
 // ---------- unittest util functions ----------
@@ -61,7 +63,8 @@ const (
 	defaultRoundDecimal   = int64(6)
 	defaultDim            = 128
 	defaultNProb          = 10
-	defaultMetricType     = "JACCARD"
+	defaultMetricType     = L2
+	defaultNQ             = 10
 
 	defaultDMLChannel   = "query-node-unittest-DML-0"
 	defaultDeltaChannel = "query-node-unittest-delta-channel-0"
@@ -89,6 +92,44 @@ const (
 	indexName = "query-node-index-0"
 )
 
+const (
+	// index type
+	IndexFaissIDMap      = "FLAT"
+	IndexFaissIVFFlat    = "IVF_FLAT"
+	IndexFaissIVFPQ      = "IVF_PQ"
+	IndexFaissIVFSQ8     = "IVF_SQ8"
+	IndexFaissIVFSQ8H    = "IVF_SQ8_HYBRID"
+	IndexFaissBinIDMap   = "BIN_FLAT"
+	IndexFaissBinIVFFlat = "BIN_IVF_FLAT"
+	IndexNsg             = "NSG"
+
+	IndexHNSW      = "HNSW"
+	IndexRHNSWFlat = "RHNSW_FLAT"
+	IndexRHNSWPQ   = "RHNSW_PQ"
+	IndexRHNSWSQ   = "RHNSW_SQ"
+	IndexANNOY     = "ANNOY"
+	IndexNGTPANNG  = "NGT_PANNG"
+	IndexNGTONNG   = "NGT_ONNG"
+
+	// metric type
+	L2       = "L2"
+	IP       = "IP"
+	hamming  = "HAMMING"
+	Jaccard  = "JACCARD"
+	tanimoto = "TANIMOTO"
+
+	nlist          = 100
+	m              = 4
+	nbits          = 8
+	nprobe         = 8
+	sliceSize      = 4
+	efConstruction = 200
+	ef             = 200
+	edgeSize       = 10
+	epsilon        = 0.1
+	maxSearchEdges = 50
+)
+
 // ---------- unittest util functions ----------
 // functions of init meta and generate meta
 type vecFieldParam struct {
@@ -222,6 +263,69 @@ func genIndexBinarySet() ([][]byte, error) {
 	return bytesSet, nil
 }
 
+func loadIndexForSegment(ctx context.Context, node *QueryNode, segmentID UniqueID, msgLength int, indexType string, metricType string) error {
+	schema := genSimpleInsertDataSchema()
+
+	// generate insert binlog
+	fieldBinlog, err := saveBinLog(ctx, defaultCollectionID, defaultPartitionID, defaultSegmentID, msgLength, schema)
+	if err != nil {
+		return err
+	}
+
+	// generate index file for segment
+	indexPaths, err := generateAndSaveIndex(segmentID, msgLength, indexType, metricType)
+	if err != nil {
+		return err
+	}
+	_, indexParams := genIndexParams(indexType, metricType)
+	indexInfo := &querypb.VecFieldIndexInfo{
+		FieldID:        simpleVecField.id,
+		EnableIndex:    true,
+		IndexName:      indexName,
+		IndexID:        indexID,
+		BuildID:        buildID,
+		IndexParams:    funcutil.Map2KeyValuePair(indexParams),
+		IndexFilePaths: indexPaths,
+	}
+
+	loader := node.loader
+	req := &querypb.LoadSegmentsRequest{
+		Base: &commonpb.MsgBase{
+			MsgType: commonpb.MsgType_LoadSegments,
+			MsgID:   rand.Int63(),
+		},
+		DstNodeID: 0,
+		Schema:    schema,
+		Infos: []*querypb.SegmentLoadInfo{
+			{
+				SegmentID:    segmentID,
+				PartitionID:  defaultPartitionID,
+				CollectionID: defaultCollectionID,
+				BinlogPaths:  fieldBinlog,
+				IndexInfos:   []*querypb.VecFieldIndexInfo{indexInfo},
+			},
+		},
+	}
+
+	err = loader.loadSegment(req, segmentTypeSealed)
+	if err != nil {
+		return err
+	}
+
+	segment, err := node.loader.historicalReplica.getSegmentByID(segmentID)
+	if err != nil {
+		return err
+	}
+	vecFieldInfo, err := segment.getVectorFieldInfo(simpleVecField.id)
+	if err != nil {
+		return err
+	}
+	if vecFieldInfo == nil {
+		return fmt.Errorf("nil vecFieldInfo, load index failed")
+	}
+	return nil
+}
+
 func generateIndex(segmentID UniqueID) ([]string, error) {
 	indexParams := genSimpleIndexParams()
 
@@ -303,6 +407,177 @@ func generateIndex(segmentID UniqueID) ([]string, error) {
 	return indexPaths, nil
 }
 
+func generateAndSaveIndex(segmentID UniqueID, msgLength int, indexType, metricType string) ([]string, error) {
+	typeParams, indexParams := genIndexParams(indexType, metricType)
+
+	var indexParamsKV []*commonpb.KeyValuePair
+	for key, value := range indexParams {
+		indexParamsKV = append(indexParamsKV, &commonpb.KeyValuePair{
+			Key:   key,
+			Value: value,
+		})
+	}
+
+	var indexRowData []float32
+	for n := 0; n < msgLength; n++ {
+		for i := 0; i < defaultDim; i++ {
+			indexRowData = append(indexRowData, rand.Float32())
+		}
+	}
+
+	index, err := indexnode.NewCIndex(typeParams, indexParams)
+	if err != nil {
+		return nil, err
+	}
+
+	err = index.BuildFloatVecIndexWithoutIds(indexRowData)
+	if err != nil {
+		return nil, err
+	}
+
+	option := &minioKV.Option{
+		Address:           Params.MinioCfg.Address,
+		AccessKeyID:       Params.MinioCfg.AccessKeyID,
+		SecretAccessKeyID: Params.MinioCfg.SecretAccessKey,
+		UseSSL:            Params.MinioCfg.UseSSL,
+		BucketName:        Params.MinioCfg.BucketName,
+		CreateBucket:      true,
+	}
+
+	kv, err := minioKV.NewMinIOKV(context.Background(), option)
+	if err != nil {
+		return nil, err
+	}
+
+	// save index to minio
+	binarySet, err := index.Serialize()
+	if err != nil {
+		return nil, err
+	}
+
+	// serialize index params
+	indexCodec := storage.NewIndexFileBinlogCodec()
+	serializedIndexBlobs, err := indexCodec.Serialize(
+		buildID,
+		0,
+		defaultCollectionID,
+		defaultPartitionID,
+		defaultSegmentID,
+		simpleVecField.id,
+		indexParams,
+		indexName,
+		indexID,
+		binarySet,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	indexPaths := make([]string, 0)
+	for _, index := range serializedIndexBlobs {
+		p := strconv.Itoa(int(segmentID)) + "/" + index.Key
+		indexPaths = append(indexPaths, p)
+		err := kv.Save(p, string(index.Value))
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return indexPaths, nil
+}
+
+func genIndexParams(indexType, metricType string) (map[string]string, map[string]string) {
+	typeParams := make(map[string]string)
+	indexParams := make(map[string]string)
+	indexParams["index_type"] = indexType
+	indexParams["metric_type"] = metricType
+	if indexType == IndexFaissIDMap { // float vector
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexFaissIVFFlat {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["nlist"] = strconv.Itoa(nlist)
+	} else if indexType == IndexFaissIVFPQ {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["nlist"] = strconv.Itoa(nlist)
+		indexParams["m"] = strconv.Itoa(m)
+		indexParams["nbits"] = strconv.Itoa(nbits)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexFaissIVFSQ8 {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["nlist"] = strconv.Itoa(nlist)
+		indexParams["nbits"] = strconv.Itoa(nbits)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexFaissIVFSQ8H {
+		// TODO: enable gpu
+	} else if indexType == IndexNsg {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["nlist"] = strconv.Itoa(163)
+		indexParams["nprobe"] = strconv.Itoa(nprobe)
+		indexParams["knng"] = strconv.Itoa(20)
+		indexParams["search_length"] = strconv.Itoa(40)
+		indexParams["out_degree"] = strconv.Itoa(30)
+		indexParams["candidate_pool_size"] = strconv.Itoa(100)
+	} else if indexType == IndexHNSW {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["M"] = strconv.Itoa(16)
+		indexParams["efConstruction"] = strconv.Itoa(efConstruction)
+		//indexParams["ef"] = strconv.Itoa(ef)
+	} else if indexType == IndexRHNSWFlat {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["m"] = strconv.Itoa(16)
+		indexParams["efConstruction"] = strconv.Itoa(efConstruction)
+		indexParams["ef"] = strconv.Itoa(ef)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexRHNSWPQ {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["m"] = strconv.Itoa(16)
+		indexParams["efConstruction"] = strconv.Itoa(efConstruction)
+		indexParams["ef"] = strconv.Itoa(ef)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+		indexParams["PQM"] = strconv.Itoa(8)
+	} else if indexType == IndexRHNSWSQ {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["m"] = strconv.Itoa(16)
+		indexParams["efConstruction"] = strconv.Itoa(efConstruction)
+		indexParams["ef"] = strconv.Itoa(ef)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexANNOY {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["n_trees"] = strconv.Itoa(4)
+		indexParams["search_k"] = strconv.Itoa(100)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexNGTPANNG {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["edge_size"] = strconv.Itoa(edgeSize)
+		indexParams["epsilon"] = fmt.Sprint(epsilon)
+		indexParams["max_search_edges"] = strconv.Itoa(maxSearchEdges)
+		indexParams["forcedly_pruned_edge_size"] = strconv.Itoa(60)
+		indexParams["selectively_pruned_edge_size"] = strconv.Itoa(30)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexNGTONNG {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["edge_size"] = strconv.Itoa(edgeSize)
+		indexParams["epsilon"] = fmt.Sprint(epsilon)
+		indexParams["max_search_edges"] = strconv.Itoa(maxSearchEdges)
+		indexParams["outgoing_edge_size"] = strconv.Itoa(5)
+		indexParams["incoming_edge_size"] = strconv.Itoa(40)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexFaissBinIVFFlat { // binary vector
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+		indexParams["nlist"] = strconv.Itoa(nlist)
+		indexParams["m"] = strconv.Itoa(m)
+		indexParams["nbits"] = strconv.Itoa(nbits)
+		indexParams["SLICE_SIZE"] = strconv.Itoa(sliceSize)
+	} else if indexType == IndexFaissBinIDMap {
+		indexParams["dim"] = strconv.Itoa(defaultDim)
+	} else {
+		panic("")
+	}
+
+	return typeParams, indexParams
+}
+
 func genSimpleSegCoreSchema() *schemapb.CollectionSchema {
 	fieldVec := genFloatVectorField(simpleVecField)
 	fieldInt := genConstantField(simpleConstField)
@@ -866,6 +1141,18 @@ func genSimpleSealedSegment() (*Segment, error) {
 		defaultMsgLength)
 }
 
+func genSealedSegmentWithMsgLength(msgLength int) (*Segment, error) {
+	schema := genSimpleSegCoreSchema()
+	schema2 := genSimpleInsertDataSchema()
+	return genSealedSegment(schema,
+		schema2,
+		defaultCollectionID,
+		defaultPartitionID,
+		defaultSegmentID,
+		defaultDMLChannel,
+		msgLength)
+}
+
 func genSimpleReplica() (ReplicaInterface, error) {
 	kv, err := genEtcdKV()
 	if err != nil {
@@ -990,13 +1277,13 @@ func genSimpleDSL() (string, error) {
 	return genDSL(schema, defaultNProb, defaultTopK, defaultRoundDecimal)
 }
 
-func genSimplePlaceHolderGroup() ([]byte, error) {
+func genPlaceHolderGroup(nq int) ([]byte, error) {
 	placeholderValue := &milvuspb.PlaceholderValue{
 		Tag:    "$0",
 		Type:   milvuspb.PlaceholderType_FloatVector,
 		Values: make([][]byte, 0),
 	}
-	for i := 0; i < int(defaultTopK); i++ {
+	for i := 0; i < nq; i++ {
 		var vec = make([]float32, defaultDim)
 		for j := 0; j < defaultDim; j++ {
 			vec[j] = rand.Float32()
@@ -1021,6 +1308,10 @@ func genSimplePlaceHolderGroup() ([]byte, error) {
 	return placeGroupByte, nil
 }
 
+func genSimplePlaceHolderGroup() ([]byte, error) {
+	return genPlaceHolderGroup(defaultNQ)
+}
+
 func genSimpleSearchPlanAndRequests() (*SearchPlan, []*searchRequest, error) {
 	schema := genSimpleSegCoreSchema()
 	collection := newCollection(defaultCollectionID, schema)
@@ -1111,8 +1402,8 @@ func genSimpleRetrievePlan() (*RetrievePlan, error) {
 	return plan, err
 }
 
-func genSimpleSearchRequest() (*internalpb.SearchRequest, error) {
-	placeHolder, err := genSimplePlaceHolderGroup()
+func genSearchRequest(nq int) (*internalpb.SearchRequest, error) {
+	placeHolder, err := genPlaceHolderGroup(nq)
 	if err != nil {
 		return nil, err
 	}
@@ -1130,6 +1421,10 @@ func genSimpleSearchRequest() (*internalpb.SearchRequest, error) {
 	}, nil
 }
 
+func genSimpleSearchRequest() (*internalpb.SearchRequest, error) {
+	return genSearchRequest(defaultNQ)
+}
+
 func genSimpleRetrieveRequest() (*internalpb.RetrieveRequest, error) {
 	expr, err := genSimpleRetrievePlanExpr()
 	if err != nil {
@@ -1149,6 +1444,19 @@ func genSimpleRetrieveRequest() (*internalpb.RetrieveRequest, error) {
 	}, nil
 }
 
+func genSearchMsg(nq int) (*msgstream.SearchMsg, error) {
+	req, err := genSearchRequest(nq)
+	if err != nil {
+		return nil, err
+	}
+	msg := &msgstream.SearchMsg{
+		BaseMsg:       genMsgStreamBaseMsg(),
+		SearchRequest: *req,
+	}
+	msg.SetTimeRecorder()
+	return msg, nil
+}
+
 func genSimpleSearchMsg() (*msgstream.SearchMsg, error) {
 	req, err := genSimpleSearchRequest()
 	if err != nil {