refactor needle write for different versions

weed/storage/needle/needle_write.go

@@ -1,145 +1,27 @@
 package needle
 
 import (
-	"bytes"
 	"fmt"
-	"math"
 
 	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
 	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
 	"github.com/seaweedfs/seaweedfs/weed/util"
-	"github.com/seaweedfs/seaweedfs/weed/util/buffer_pool"
 )
 
-func (n *Needle) prepareWriteBuffer(version Version, writeBytes *bytes.Buffer) (Size, int64, error) {
-	writeBytes.Reset()
-	switch version {
-	case Version1:
-		header := make([]byte, NeedleHeaderSize)
-		CookieToBytes(header[0:CookieSize], n.Cookie)
-		NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
-		n.Size = Size(len(n.Data))
-		SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
-		size := n.Size
-		actualSize := NeedleHeaderSize + int64(n.Size)
-		writeBytes.Write(header)
-		writeBytes.Write(n.Data)
-		padding := PaddingLength(n.Size, version)
-		util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
-		writeBytes.Write(header[0 : NeedleChecksumSize+padding])
-		return size, actualSize, nil
-	case Version2, Version3:
-		header := make([]byte, NeedleHeaderSize+TimestampSize) // adding timestamp to reuse it and avoid extra allocation
-		CookieToBytes(header[0:CookieSize], n.Cookie)
-		NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
-		if len(n.Name) >= math.MaxUint8 {
-			n.NameSize = math.MaxUint8
-		} else {
-			n.NameSize = uint8(len(n.Name))
-		}
-		n.DataSize, n.MimeSize = uint32(len(n.Data)), uint8(len(n.Mime))
-		if n.DataSize > 0 {
-			n.Size = 4 + Size(n.DataSize) + 1
-			if n.HasName() {
-				n.Size = n.Size + 1 + Size(n.NameSize)
-			}
-			if n.HasMime() {
-				n.Size = n.Size + 1 + Size(n.MimeSize)
-			}
-			if n.HasLastModifiedDate() {
-				n.Size = n.Size + LastModifiedBytesLength
-			}
-			if n.HasTtl() {
-				n.Size = n.Size + TtlBytesLength
-			}
-			if n.HasPairs() {
-				n.Size += 2 + Size(n.PairsSize)
-			}
-		} else {
-			n.Size = 0
-		}
-		SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
-		writeBytes.Write(header[0:NeedleHeaderSize])
-		if n.DataSize > 0 {
-			util.Uint32toBytes(header[0:4], n.DataSize)
-			writeBytes.Write(header[0:4])
-			writeBytes.Write(n.Data)
-			util.Uint8toBytes(header[0:1], n.Flags)
-			writeBytes.Write(header[0:1])
-			if n.HasName() {
-				util.Uint8toBytes(header[0:1], n.NameSize)
-				writeBytes.Write(header[0:1])
-				writeBytes.Write(n.Name[:n.NameSize])
-			}
-			if n.HasMime() {
-				util.Uint8toBytes(header[0:1], n.MimeSize)
-				writeBytes.Write(header[0:1])
-				writeBytes.Write(n.Mime)
-			}
-			if n.HasLastModifiedDate() {
-				util.Uint64toBytes(header[0:8], n.LastModified)
-				writeBytes.Write(header[8-LastModifiedBytesLength : 8])
-			}
-			if n.HasTtl() && n.Ttl != nil {
-				n.Ttl.ToBytes(header[0:TtlBytesLength])
-				writeBytes.Write(header[0:TtlBytesLength])
-			}
-			if n.HasPairs() {
-				util.Uint16toBytes(header[0:2], n.PairsSize)
-				writeBytes.Write(header[0:2])
-				writeBytes.Write(n.Pairs)
-			}
-		}
-		padding := PaddingLength(n.Size, version)
-		util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
-		if version == Version2 {
-			writeBytes.Write(header[0 : NeedleChecksumSize+padding])
-		} else {
-			// version3
-			util.Uint64toBytes(header[NeedleChecksumSize:NeedleChecksumSize+TimestampSize], n.AppendAtNs)
-			writeBytes.Write(header[0 : NeedleChecksumSize+TimestampSize+padding])
-		}
-
-		return Size(n.DataSize), GetActualSize(n.Size, version), nil
-	}
-
-	return 0, 0, fmt.Errorf("Unsupported Version! (%d)", version)
-}
-
 func (n *Needle) Append(w backend.BackendStorageFile, version Version) (offset uint64, size Size, actualSize int64, err error) {
 
-	if end, _, e := w.GetStat(); e == nil {
-		defer func(w backend.BackendStorageFile, off int64) {
-			if err != nil {
-				if te := w.Truncate(end); te != nil {
-					glog.V(0).Infof("Failed to truncate %s back to %d with error: %v", w.Name(), end, te)
-				}
-			}
-		}(w, end)
-		offset = uint64(end)
-	} else {
-		err = fmt.Errorf("Cannot Read Current Volume Position: %w", e)
+	switch version {
+	case Version1:
+		return writeNeedleV1(w, n)
+	case Version2:
+		return writeNeedleV2(w, n)
+	case Version3:
+		return writeNeedleV3(w, n)
+	default:
+		err = fmt.Errorf("unsupported version: %d", version)
 		return
 	}
-	if offset >= MaxPossibleVolumeSize && len(n.Data) != 0 {
-		err = fmt.Errorf("Volume Size %d Exceeded %d", offset, MaxPossibleVolumeSize)
-		return
-	}
-
-	bytesBuffer := buffer_pool.SyncPoolGetBuffer()
-	defer buffer_pool.SyncPoolPutBuffer(bytesBuffer)
-
-	size, actualSize, err = n.prepareWriteBuffer(version, bytesBuffer)
-
-	if err == nil {
-		_, err = w.WriteAt(bytesBuffer.Bytes(), int64(offset))
-		if err != nil {
-			err = fmt.Errorf("failed to write %d bytes to %s at offset %d: %w", actualSize, w.Name(), offset, err)
-		}
-	}
-
-	return offset, size, actualSize, err
 }
 
 func WriteNeedleBlob(w backend.BackendStorageFile, dataSlice []byte, size Size, appendAtNs uint64, version Version) (offset uint64, err error) {

weed/storage/needle/needle_write_legacy.go

@@ -0,0 +1,142 @@
+package needle
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
+	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+	"github.com/seaweedfs/seaweedfs/weed/util/buffer_pool"
+)
+
+func (n *Needle) LegacyPrepareWriteBuffer(version Version, writeBytes *bytes.Buffer) (Size, int64, error) {
+	writeBytes.Reset()
+	switch version {
+	case Version1:
+		header := make([]byte, NeedleHeaderSize)
+		CookieToBytes(header[0:CookieSize], n.Cookie)
+		NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
+		n.Size = Size(len(n.Data))
+		SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
+		size := n.Size
+		actualSize := NeedleHeaderSize + int64(n.Size)
+		writeBytes.Write(header)
+		writeBytes.Write(n.Data)
+		padding := PaddingLength(n.Size, version)
+		util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
+		writeBytes.Write(header[0 : NeedleChecksumSize+padding])
+		return size, actualSize, nil
+	case Version2, Version3:
+		header := make([]byte, NeedleHeaderSize+TimestampSize) // adding timestamp to reuse it and avoid extra allocation
+		CookieToBytes(header[0:CookieSize], n.Cookie)
+		NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
+		if len(n.Name) >= math.MaxUint8 {
+			n.NameSize = math.MaxUint8
+		} else {
+			n.NameSize = uint8(len(n.Name))
+		}
+		n.DataSize, n.MimeSize = uint32(len(n.Data)), uint8(len(n.Mime))
+		if n.DataSize > 0 {
+			n.Size = 4 + Size(n.DataSize) + 1
+			if n.HasName() {
+				n.Size = n.Size + 1 + Size(n.NameSize)
+			}
+			if n.HasMime() {
+				n.Size = n.Size + 1 + Size(n.MimeSize)
+			}
+			if n.HasLastModifiedDate() {
+				n.Size = n.Size + LastModifiedBytesLength
+			}
+			if n.HasTtl() {
+				n.Size = n.Size + TtlBytesLength
+			}
+			if n.HasPairs() {
+				n.Size += 2 + Size(n.PairsSize)
+			}
+		} else {
+			n.Size = 0
+		}
+		SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
+		writeBytes.Write(header[0:NeedleHeaderSize])
+		if n.DataSize > 0 {
+			util.Uint32toBytes(header[0:4], n.DataSize)
+			writeBytes.Write(header[0:4])
+			writeBytes.Write(n.Data)
+			util.Uint8toBytes(header[0:1], n.Flags)
+			writeBytes.Write(header[0:1])
+			if n.HasName() {
+				util.Uint8toBytes(header[0:1], n.NameSize)
+				writeBytes.Write(header[0:1])
+				writeBytes.Write(n.Name[:n.NameSize])
+			}
+			if n.HasMime() {
+				util.Uint8toBytes(header[0:1], n.MimeSize)
+				writeBytes.Write(header[0:1])
+				writeBytes.Write(n.Mime)
+			}
+			if n.HasLastModifiedDate() {
+				util.Uint64toBytes(header[0:8], n.LastModified)
+				writeBytes.Write(header[8-LastModifiedBytesLength : 8])
+			}
+			if n.HasTtl() && n.Ttl != nil {
+				n.Ttl.ToBytes(header[0:TtlBytesLength])
+				writeBytes.Write(header[0:TtlBytesLength])
+			}
+			if n.HasPairs() {
+				util.Uint16toBytes(header[0:2], n.PairsSize)
+				writeBytes.Write(header[0:2])
+				writeBytes.Write(n.Pairs)
+			}
+		}
+		padding := PaddingLength(n.Size, version)
+		util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
+		if version == Version2 {
+			writeBytes.Write(header[0 : NeedleChecksumSize+padding])
+		} else {
+			// version3
+			util.Uint64toBytes(header[NeedleChecksumSize:NeedleChecksumSize+TimestampSize], n.AppendAtNs)
+			writeBytes.Write(header[0 : NeedleChecksumSize+TimestampSize+padding])
+		}
+
+		return Size(n.DataSize), GetActualSize(n.Size, version), nil
+	}
+
+	return 0, 0, fmt.Errorf("Unsupported Version! (%d)", version)
+}
+
+func (n *Needle) LegacyAppend(w backend.BackendStorageFile, version Version) (offset uint64, size Size, actualSize int64, err error) {
+	if end, _, e := w.GetStat(); e == nil {
+		defer func(w backend.BackendStorageFile, off int64) {
+			if err != nil {
+				if te := w.Truncate(end); te != nil {
+					glog.V(0).Infof("Failed to truncate %s back to %d with error: %v", w.Name(), end, te)
+				}
+			}
+		}(w, end)
+		offset = uint64(end)
+	} else {
+		err = fmt.Errorf("Cannot Read Current Volume Position: %w", e)
+		return
+	}
+	if offset >= MaxPossibleVolumeSize && len(n.Data) != 0 {
+		err = fmt.Errorf("Volume Size %d Exceeded %d", offset, MaxPossibleVolumeSize)
+		return
+	}
+
+	bytesBuffer := buffer_pool.SyncPoolGetBuffer()
+	defer buffer_pool.SyncPoolPutBuffer(bytesBuffer)
+
+	size, actualSize, err = n.LegacyPrepareWriteBuffer(version, bytesBuffer)
+
+	if err == nil {
+		_, err = w.WriteAt(bytesBuffer.Bytes(), int64(offset))
+		if err != nil {
+			err = fmt.Errorf("failed to write %d bytes to %s at offset %d: %w", actualSize, w.Name(), offset, err)
+		}
+	}
+
+	return offset, size, actualSize, err
+}

weed/storage/needle/needle_write_test.go

@@ -1,8 +1,10 @@
 package needle
 
 import (
+	"bytes"
 	"os"
 	"testing"
+	"time"
 
 	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
 	"github.com/seaweedfs/seaweedfs/weed/storage/types"
@@ -62,3 +64,96 @@ func TestAppend(t *testing.T) {
 		t.Errorf("Fail to Append Needle.")
 	}
 }
+
+func versionString(v Version) string {
+	switch v {
+	case Version1:
+		return "Version1"
+	case Version2:
+		return "Version2"
+	case Version3:
+		return "Version3"
+	default:
+		return "UnknownVersion"
+	}
+}
+
+func TestWriteNeedle_CompatibilityWithLegacy(t *testing.T) {
+	versions := []Version{Version1, Version2, Version3}
+	for _, version := range versions {
+		t.Run(versionString(version), func(t *testing.T) {
+			n := &Needle{
+				Cookie:       0x12345678,
+				Id:           0x1122334455667788,
+				Data:         []byte("hello world"),
+				Flags:        0xFF,
+				Name:         []byte("filename.txt"),
+				Mime:         []byte("text/plain"),
+				LastModified: 0x1234567890,
+				Ttl:          nil, // Add TTL if needed
+				Pairs:        []byte("key=value"),
+				PairsSize:    9,
+				Checksum:     0xCAFEBABE,
+				AppendAtNs:   0xDEADBEEF,
+			}
+
+			// Legacy
+			legacyBuf := &bytes.Buffer{}
+			_, _, err := n.LegacyPrepareWriteBuffer(version, legacyBuf)
+			if err != nil {
+				t.Fatalf("LegacyPrepareWriteBuffer failed: %v", err)
+			}
+
+			// New
+			newBuf := &bytes.Buffer{}
+			switch version {
+			case Version1:
+				_, _, _, err = writeNeedleV1(&mockBackendWriter{buf: newBuf}, n)
+			case Version2:
+				_, _, _, err = writeNeedleV2(&mockBackendWriter{buf: newBuf}, n)
+			case Version3:
+				_, _, _, err = writeNeedleV3(&mockBackendWriter{buf: newBuf}, n)
+			}
+			if err != nil {
+				t.Fatalf("writeNeedleV%d failed: %v", version, err)
+			}
+
+			if !bytes.Equal(legacyBuf.Bytes(), newBuf.Bytes()) {
+				t.Errorf("Data layout mismatch for version %d\nLegacy: %x\nNew:    %x", version, legacyBuf.Bytes(), newBuf.Bytes())
+			}
+		})
+	}
+}
+
+type mockBackendWriter struct {
+	buf *bytes.Buffer
+}
+
+func (m *mockBackendWriter) WriteAt(p []byte, off int64) (n int, err error) {
+	return m.buf.Write(p)
+}
+
+func (m *mockBackendWriter) GetStat() (int64, time.Time, error) {
+	return 0, time.Time{}, nil
+}
+
+func (m *mockBackendWriter) Truncate(size int64) error {
+	return nil
+}
+
+func (m *mockBackendWriter) Name() string {
+	return "mock"
+}
+
+func (m *mockBackendWriter) Close() error {
+	return nil
+}
+
+func (m *mockBackendWriter) Sync() error {
+	return nil
+}
+
+func (m *mockBackendWriter) ReadAt(p []byte, off int64) (n int, err error) {
+	// Not used in this test
+	return 0, nil
+}

weed/storage/needle/needle_write_v1.go

@@ -0,0 +1,54 @@
+package needle
+
+import (
+	"fmt"
+
+	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
+	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+	"github.com/seaweedfs/seaweedfs/weed/util/buffer_pool"
+)
+
+func writeNeedleV1(w backend.BackendStorageFile, n *Needle) (offset uint64, size Size, actualSize int64, err error) {
+	if end, _, e := w.GetStat(); e == nil {
+		defer func(w backend.BackendStorageFile, off int64) {
+			if err != nil {
+				if te := w.Truncate(end); te != nil {
+					// handle error
+				}
+			}
+		}(w, end)
+		offset = uint64(end)
+	} else {
+		err = fmt.Errorf("Cannot Read Current Volume Position: %w", e)
+		return
+	}
+	if offset >= MaxPossibleVolumeSize && len(n.Data) != 0 {
+		err = fmt.Errorf("Volume Size %d Exceeded %d", offset, MaxPossibleVolumeSize)
+		return
+	}
+
+	bytesBuffer := buffer_pool.SyncPoolGetBuffer()
+	defer buffer_pool.SyncPoolPutBuffer(bytesBuffer)
+
+	bytesBuffer.Reset()
+	header := make([]byte, NeedleHeaderSize)
+	CookieToBytes(header[0:CookieSize], n.Cookie)
+	NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
+	n.Size = Size(len(n.Data))
+	SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
+	size = n.Size
+	actualSize = NeedleHeaderSize + int64(n.Size)
+	bytesBuffer.Write(header)
+	bytesBuffer.Write(n.Data)
+	padding := PaddingLength(n.Size, Version1)
+	util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
+	bytesBuffer.Write(header[0 : NeedleChecksumSize+padding])
+
+	_, err = w.WriteAt(bytesBuffer.Bytes(), int64(offset))
+	if err != nil {
+		err = fmt.Errorf("failed to write %d bytes to %s at offset %d: %w", actualSize, w.Name(), offset, err)
+	}
+
+	return offset, size, actualSize, err
+}

weed/storage/needle/needle_write_v2.go

@@ -0,0 +1,109 @@
+package needle
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
+	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+	"github.com/seaweedfs/seaweedfs/weed/util/buffer_pool"
+)
+
+func writeNeedleV2(w backend.BackendStorageFile, n *Needle) (offset uint64, size Size, actualSize int64, err error) {
+	if end, _, e := w.GetStat(); e == nil {
+		defer func(w backend.BackendStorageFile, off int64) {
+			if err != nil {
+				if te := w.Truncate(end); te != nil {
+					// handle error
+				}
+			}
+		}(w, end)
+		offset = uint64(end)
+	} else {
+		err = fmt.Errorf("Cannot Read Current Volume Position: %w", e)
+		return
+	}
+	if offset >= MaxPossibleVolumeSize && len(n.Data) != 0 {
+		err = fmt.Errorf("Volume Size %d Exceeded %d", offset, MaxPossibleVolumeSize)
+		return
+	}
+
+	bytesBuffer := buffer_pool.SyncPoolGetBuffer()
+	defer buffer_pool.SyncPoolPutBuffer(bytesBuffer)
+
+	bytesBuffer.Reset()
+	header := make([]byte, NeedleHeaderSize+TimestampSize)
+	CookieToBytes(header[0:CookieSize], n.Cookie)
+	NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
+	if len(n.Name) >= math.MaxUint8 {
+		n.NameSize = math.MaxUint8
+	} else {
+		n.NameSize = uint8(len(n.Name))
+	}
+	n.DataSize, n.MimeSize = uint32(len(n.Data)), uint8(len(n.Mime))
+	if n.DataSize > 0 {
+		n.Size = 4 + Size(n.DataSize) + 1
+		if n.HasName() {
+			n.Size = n.Size + 1 + Size(n.NameSize)
+		}
+		if n.HasMime() {
+			n.Size = n.Size + 1 + Size(n.MimeSize)
+		}
+		if n.HasLastModifiedDate() {
+			n.Size = n.Size + LastModifiedBytesLength
+		}
+		if n.HasTtl() {
+			n.Size = n.Size + TtlBytesLength
+		}
+		if n.HasPairs() {
+			n.Size += 2 + Size(n.PairsSize)
+		}
+	} else {
+		n.Size = 0
+	}
+	SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
+	bytesBuffer.Write(header[0:NeedleHeaderSize])
+	if n.DataSize > 0 {
+		util.Uint32toBytes(header[0:4], n.DataSize)
+		bytesBuffer.Write(header[0:4])
+		bytesBuffer.Write(n.Data)
+		util.Uint8toBytes(header[0:1], n.Flags)
+		bytesBuffer.Write(header[0:1])
+		if n.HasName() {
+			util.Uint8toBytes(header[0:1], n.NameSize)
+			bytesBuffer.Write(header[0:1])
+			bytesBuffer.Write(n.Name[:n.NameSize])
+		}
+		if n.HasMime() {
+			util.Uint8toBytes(header[0:1], n.MimeSize)
+			bytesBuffer.Write(header[0:1])
+			bytesBuffer.Write(n.Mime)
+		}
+		if n.HasLastModifiedDate() {
+			util.Uint64toBytes(header[0:8], n.LastModified)
+			bytesBuffer.Write(header[8-LastModifiedBytesLength : 8])
+		}
+		if n.HasTtl() && n.Ttl != nil {
+			n.Ttl.ToBytes(header[0:TtlBytesLength])
+			bytesBuffer.Write(header[0:TtlBytesLength])
+		}
+		if n.HasPairs() {
+			util.Uint16toBytes(header[0:2], n.PairsSize)
+			bytesBuffer.Write(header[0:2])
+			bytesBuffer.Write(n.Pairs)
+		}
+	}
+	padding := PaddingLength(n.Size, Version2)
+	util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
+	bytesBuffer.Write(header[0 : NeedleChecksumSize+padding])
+
+	size = Size(n.DataSize)
+	actualSize = GetActualSize(n.Size, Version2)
+	_, err = w.WriteAt(bytesBuffer.Bytes(), int64(offset))
+	if err != nil {
+		err = fmt.Errorf("failed to write %d bytes to %s at offset %d: %w", actualSize, w.Name(), offset, err)
+	}
+
+	return offset, size, actualSize, err
+}

weed/storage/needle/needle_write_v3.go

@@ -0,0 +1,110 @@
+package needle
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
+	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+	"github.com/seaweedfs/seaweedfs/weed/util/buffer_pool"
+)
+
+func writeNeedleV3(w backend.BackendStorageFile, n *Needle) (offset uint64, size Size, actualSize int64, err error) {
+	if end, _, e := w.GetStat(); e == nil {
+		defer func(w backend.BackendStorageFile, off int64) {
+			if err != nil {
+				if te := w.Truncate(end); te != nil {
+					// handle error
+				}
+			}
+		}(w, end)
+		offset = uint64(end)
+	} else {
+		err = fmt.Errorf("Cannot Read Current Volume Position: %w", e)
+		return
+	}
+	if offset >= MaxPossibleVolumeSize && len(n.Data) != 0 {
+		err = fmt.Errorf("Volume Size %d Exceeded %d", offset, MaxPossibleVolumeSize)
+		return
+	}
+
+	bytesBuffer := buffer_pool.SyncPoolGetBuffer()
+	defer buffer_pool.SyncPoolPutBuffer(bytesBuffer)
+
+	bytesBuffer.Reset()
+	header := make([]byte, NeedleHeaderSize+TimestampSize)
+	CookieToBytes(header[0:CookieSize], n.Cookie)
+	NeedleIdToBytes(header[CookieSize:CookieSize+NeedleIdSize], n.Id)
+	if len(n.Name) >= math.MaxUint8 {
+		n.NameSize = math.MaxUint8
+	} else {
+		n.NameSize = uint8(len(n.Name))
+	}
+	n.DataSize, n.MimeSize = uint32(len(n.Data)), uint8(len(n.Mime))
+	if n.DataSize > 0 {
+		n.Size = 4 + Size(n.DataSize) + 1
+		if n.HasName() {
+			n.Size = n.Size + 1 + Size(n.NameSize)
+		}
+		if n.HasMime() {
+			n.Size = n.Size + 1 + Size(n.MimeSize)
+		}
+		if n.HasLastModifiedDate() {
+			n.Size = n.Size + LastModifiedBytesLength
+		}
+		if n.HasTtl() {
+			n.Size = n.Size + TtlBytesLength
+		}
+		if n.HasPairs() {
+			n.Size += 2 + Size(n.PairsSize)
+		}
+	} else {
+		n.Size = 0
+	}
+	SizeToBytes(header[CookieSize+NeedleIdSize:CookieSize+NeedleIdSize+SizeSize], n.Size)
+	bytesBuffer.Write(header[0:NeedleHeaderSize])
+	if n.DataSize > 0 {
+		util.Uint32toBytes(header[0:4], n.DataSize)
+		bytesBuffer.Write(header[0:4])
+		bytesBuffer.Write(n.Data)
+		util.Uint8toBytes(header[0:1], n.Flags)
+		bytesBuffer.Write(header[0:1])
+		if n.HasName() {
+			util.Uint8toBytes(header[0:1], n.NameSize)
+			bytesBuffer.Write(header[0:1])
+			bytesBuffer.Write(n.Name[:n.NameSize])
+		}
+		if n.HasMime() {
+			util.Uint8toBytes(header[0:1], n.MimeSize)
+			bytesBuffer.Write(header[0:1])
+			bytesBuffer.Write(n.Mime)
+		}
+		if n.HasLastModifiedDate() {
+			util.Uint64toBytes(header[0:8], n.LastModified)
+			bytesBuffer.Write(header[8-LastModifiedBytesLength : 8])
+		}
+		if n.HasTtl() && n.Ttl != nil {
+			n.Ttl.ToBytes(header[0:TtlBytesLength])
+			bytesBuffer.Write(header[0:TtlBytesLength])
+		}
+		if n.HasPairs() {
+			util.Uint16toBytes(header[0:2], n.PairsSize)
+			bytesBuffer.Write(header[0:2])
+			bytesBuffer.Write(n.Pairs)
+		}
+	}
+	padding := PaddingLength(n.Size, Version3)
+	util.Uint32toBytes(header[0:NeedleChecksumSize], uint32(n.Checksum))
+	util.Uint64toBytes(header[NeedleChecksumSize:NeedleChecksumSize+TimestampSize], n.AppendAtNs)
+	bytesBuffer.Write(header[0 : NeedleChecksumSize+TimestampSize+padding])
+
+	size = Size(n.DataSize)
+	actualSize = GetActualSize(n.Size, Version3)
+	_, err = w.WriteAt(bytesBuffer.Bytes(), int64(offset))
+	if err != nil {
+		err = fmt.Errorf("failed to write %d bytes to %s at offset %d: %w", actualSize, w.Name(), offset, err)
+	}
+
+	return offset, size, actualSize, err
+}