enhance: [2.4] Preallocate delete data slice to avoid growslice (#37044)

Rewritten based on master pr
pr: #37043

Related to #36887

Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>

internal/datacoord/import_task.go

@@ -17,11 +17,11 @@
 package datacoord
 
 import (
-	"github.com/milvus-io/milvus/pkg/util/funcutil"
-	"github.com/milvus-io/milvus/pkg/util/paramtable"
 	"google.golang.org/protobuf/proto"
 
 	"github.com/milvus-io/milvus/internal/proto/datapb"
+	"github.com/milvus-io/milvus/pkg/util/funcutil"
+	"github.com/milvus-io/milvus/pkg/util/paramtable"
 	"github.com/milvus-io/milvus/pkg/util/timerecord"
 )
 

internal/querynodev2/segments/segment_loader.go

@@ -1395,8 +1395,9 @@ func (loader *segmentLoader) LoadDeltaLogs(ctx context.Context, segment Segment,
 					return nil, err
 				}
 				blob := &storage.Blob{
-					Key:   bLog.GetLogPath(),
-					Value: value,
+					Key:    bLog.GetLogPath(),
+					Value:  value,
+					RowNum: bLog.EntriesNum,
 				}
 				return blob, nil
 			})

internal/storage/data_codec.go

@@ -23,6 +23,8 @@ import (
 	"math"
 	"sort"
 
+	"github.com/samber/lo"
+
 	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
 	"github.com/milvus-io/milvus/internal/proto/etcdpb"
 	"github.com/milvus-io/milvus/pkg/common"
@@ -868,7 +870,13 @@ func (deleteCodec *DeleteCodec) Deserialize(blobs []*Blob) (partitionID UniqueID
 	}
 
 	var pid, sid UniqueID
-	result := &DeleteData{}
+	rowNums := lo.SumBy(blobs, func(blob *Blob) int64 {
+		return blob.RowNum
+	})
+	result := &DeleteData{
+		Pks: make([]PrimaryKey, 0, rowNums),
+		Tss: make([]uint64, 0, rowNums),
+	}
 
 	deserializeBlob := func(blob *Blob) error {
 		binlogReader, err := NewBinlogReader(blob.Value)