diff --git a/weed/storage/memory_map/memory_map.go b/weed/storage/memory_map/memory_map.go
index 4baf6fc1f..5f0327ea7 100644
--- a/weed/storage/memory_map/memory_map.go
+++ b/weed/storage/memory_map/memory_map.go
@@ -25,16 +25,16 @@ type MemoryMap struct {
 
 var FileMemoryMap = make(map[string]*MemoryMap)
 
-func (mMap *MemoryMap) WriteMemory(offset uint64, length uint64, data []byte) {
-
+func (mMap *MemoryMap) CreateMemoryMap(file *os.File, maxLength uint64) {
 }
 
-func (mMap *MemoryMap) ReadMemory(offset uint64, length uint64) (MemoryBuffer, error) {
-	return MemoryBuffer{}, fmt.Errorf("Memory Map not implemented for this platform")
-}
+func (mMap *MemoryMap) WriteMemory(offset uint64, length uint64, data []byte) {
 
-func (mBuffer *MemoryBuffer) ReleaseMemory() {
+}
 
+func (mMap *MemoryMap) ReadMemory(offset uint64, length uint64) ([]byte, error) {
+	dataSlice := []byte{}
+	return dataSlice, fmt.Errorf("Memory Map not implemented for this platform")
 }
 
 func (mBuffer *MemoryMap) DeleteFileAndMemoryMap() {
diff --git a/weed/storage/memory_map/memory_map_windows.go b/weed/storage/memory_map/memory_map_windows.go
index a06b7947c..ac4493188 100644
--- a/weed/storage/memory_map/memory_map_windows.go
+++ b/weed/storage/memory_map/memory_map_windows.go
@@ -48,7 +48,7 @@ var currentMaxWorkingSet uint64 = 0
 var _ = getProcessWorkingSetSize(uintptr(currentProcess), &currentMinWorkingSet, &currentMaxWorkingSet)
 
 var systemInfo, _ = getSystemInfo()
-var chunkSize = uint64(systemInfo.dwAllocationGranularity) * 256
+var chunkSize = uint64(systemInfo.dwAllocationGranularity) * 128
 
 var memoryStatusEx, _ = globalMemoryStatusEx()
 var maxMemoryLimitBytes = uint64(float64(memoryStatusEx.ullTotalPhys) * 0.8)
@@ -82,7 +82,7 @@ func (mMap *MemoryMap) DeleteFileAndMemoryMap() {
 	windows.CloseHandle(windows.Handle(mMap.File.Fd()))
 
 	for _, view := range mMap.write_map_views {
-		view.ReleaseMemory()
+		view.releaseMemory()
 	}
 
 	mMap.write_map_views = nil
@@ -130,17 +130,21 @@ func (mMap *MemoryMap) WriteMemory(offset uint64, length uint64, data []byte) {
 	}
 }
 
-func (mMap *MemoryMap) ReadMemory(offset uint64, length uint64) (MemoryBuffer, error) {
-	return allocate(windows.Handle(mMap.file_memory_map_handle), offset, length, false)
+func (mMap *MemoryMap) ReadMemory(offset uint64, length uint64) (dataSlice []byte, err error) {
+	dataSlice = make([]byte, length)
+	mBuffer, err := allocate(windows.Handle(mMap.file_memory_map_handle), offset, length, false)
+	copy(dataSlice, mBuffer.Buffer)
+	mBuffer.releaseMemory()
+	return dataSlice, err
 }
 
-func (mBuffer *MemoryBuffer) ReleaseMemory() {
+func (mBuffer *MemoryBuffer) releaseMemory() {
 
 	windows.VirtualUnlock(mBuffer.aligned_ptr, uintptr(mBuffer.aligned_length))
 	windows.UnmapViewOfFile(mBuffer.aligned_ptr)
 
-	currentMinWorkingSet = currentMinWorkingSet - mBuffer.aligned_length
-	currentMaxWorkingSet = currentMaxWorkingSet - mBuffer.aligned_length
+	currentMinWorkingSet -= mBuffer.aligned_length
+	currentMaxWorkingSet -= mBuffer.aligned_length
 
 	if currentMinWorkingSet < maxMemoryLimitBytes {
 		var _ = setProcessWorkingSetSize(uintptr(currentProcess), currentMinWorkingSet, currentMaxWorkingSet)
@@ -182,8 +186,8 @@ func allocate(hMapFile windows.Handle, offset uint64, length uint64, write bool)
 		access = windows.FILE_MAP_WRITE
 	}
 
-	currentMinWorkingSet = currentMinWorkingSet + aligned_length
-	currentMaxWorkingSet = currentMaxWorkingSet + aligned_length
+	currentMinWorkingSet += aligned_length
+	currentMaxWorkingSet += aligned_length
 
 	if currentMinWorkingSet < maxMemoryLimitBytes {
 		// increase the process working set size to hint to windows memory manager to
diff --git a/weed/storage/needle/needle_read_write.go b/weed/storage/needle/needle_read_write.go
index 3fe6a246c..5f8bfee8b 100644
--- a/weed/storage/needle/needle_read_write.go
+++ b/weed/storage/needle/needle_read_write.go
@@ -164,13 +164,11 @@ func (n *Needle) Append(w *os.File, version Version) (offset uint64, size uint32
 func ReadNeedleBlob(r *os.File, offset int64, size uint32, version Version) (dataSlice []byte, err error) {
 
 	dataSize := GetActualSize(size, version)
-	dataSlice = make([]byte, dataSize)
+	dataSlice = make([]byte, int(dataSize))
 
 	mMap, exists := memory_map.FileMemoryMap[r.Name()]
 	if exists {
-		mBuffer, err := mMap.ReadMemory(uint64(offset), uint64(dataSize))
-		copy(dataSlice, mBuffer.Buffer)
-		mBuffer.ReleaseMemory()
+		dataSlice, err := mMap.ReadMemory(uint64(offset), uint64(dataSize))
 		return dataSlice, err
 	} else {
 		_, err = r.ReadAt(dataSlice, offset)
@@ -291,10 +289,7 @@ func ReadNeedleHeader(r *os.File, version Version, offset int64) (n *Needle, byt
 
 		mMap, exists := memory_map.FileMemoryMap[r.Name()]
 		if exists {
-			mBuffer, err := mMap.ReadMemory(uint64(offset), NeedleHeaderSize)
-			copy(bytes, mBuffer.Buffer)
-			mBuffer.ReleaseMemory()
-
+			bytes, err = mMap.ReadMemory(uint64(offset), NeedleHeaderSize)
 			if err != nil {
 				return nil, bytes, 0, err
 			}
diff --git a/weed/storage/volume_super_block.go b/weed/storage/volume_super_block.go
index 7df733b57..414d55f68 100644
--- a/weed/storage/volume_super_block.go
+++ b/weed/storage/volume_super_block.go
@@ -113,13 +113,11 @@ func ReadSuperBlock(dataFile *os.File) (superBlock SuperBlock, err error) {
 	header := make([]byte, _SuperBlockSize)
 	mMap, exists := memory_map.FileMemoryMap[dataFile.Name()]
 	if exists {
-		mBuffer, e := mMap.ReadMemory(0, _SuperBlockSize)
+		header, err = mMap.ReadMemory(0, _SuperBlockSize)
 		if err != nil {
-			err = fmt.Errorf("cannot read volume %s super block: %v", dataFile.Name(), e)
+			err = fmt.Errorf("cannot read volume %s super block: %v", dataFile.Name(), err)
 			return
 		}
-		copy(header, mBuffer.Buffer)
-		mBuffer.ReleaseMemory()
 	} else {
 		if _, err = dataFile.Seek(0, 0); err != nil {
 			err = fmt.Errorf("cannot seek to the beginning of %s: %v", dataFile.Name(), err)