diff --git a/weed/filer2/filechunks.go b/weed/filer2/filechunks.go
index 9ab7ea355..764ba6060 100644
--- a/weed/filer2/filechunks.go
+++ b/weed/filer2/filechunks.go
@@ -158,9 +158,9 @@ func logPrintf(name string, visibles []VisibleInterval) {
 	/*
 		glog.V(0).Infof("%s len %d", name, len(visibles))
 		for _, v := range visibles {
-			glog.V(0).Infof("%s:  [%d,%d)", name, v.start, v.stop)
+			glog.V(0).Infof("%s:  [%d,%d) %s %d", name, v.start, v.stop, v.fileId, v.chunkOffset)
 		}
-	*/
+	 */
 }
 
 var bufPool = sync.Pool{
@@ -169,7 +169,7 @@ var bufPool = sync.Pool{
 	},
 }
 
-func MergeIntoVisibles(visibles, newVisibles []VisibleInterval, chunk *filer_pb.FileChunk) []VisibleInterval {
+func MergeIntoVisibles(visibles []VisibleInterval, chunk *filer_pb.FileChunk) (newVisibles []VisibleInterval) {
 
 	newV := newVisibleInterval(chunk.Offset, chunk.Offset+int64(chunk.Size), chunk.GetFileIdString(), chunk.Mtime, 0, chunk.Size, chunk.CipherKey, chunk.IsCompressed)
 
@@ -183,16 +183,22 @@ func MergeIntoVisibles(visibles, newVisibles []VisibleInterval, chunk *filer_pb.
 	}
 
 	logPrintf("  before", visibles)
+	// glog.V(0).Infof("newVisibles %d adding chunk [%d,%d) %s size:%d", len(newVisibles), chunk.Offset, chunk.Offset+int64(chunk.Size), chunk.GetFileIdString(), chunk.Size)
 	chunkStop := chunk.Offset + int64(chunk.Size)
 	for _, v := range visibles {
 		if v.start < chunk.Offset && chunk.Offset < v.stop {
-			newVisibles = append(newVisibles, newVisibleInterval(v.start, chunk.Offset, v.fileId, v.modifiedTime, v.chunkOffset, v.chunkSize, v.cipherKey, v.isGzipped))
+			t := newVisibleInterval(v.start, chunk.Offset, v.fileId, v.modifiedTime, v.chunkOffset, v.chunkSize, v.cipherKey, v.isGzipped)
+			newVisibles = append(newVisibles, t)
+			// glog.V(0).Infof("visible %d [%d,%d) =1> [%d,%d)", i, v.start, v.stop, t.start, t.stop)
 		}
 		if v.start < chunkStop && chunkStop < v.stop {
-			newVisibles = append(newVisibles, newVisibleInterval(chunkStop, v.stop, v.fileId, v.modifiedTime, v.chunkOffset+(chunkStop-v.start), v.chunkSize, v.cipherKey, v.isGzipped))
+			t := newVisibleInterval(chunkStop, v.stop, v.fileId, v.modifiedTime, v.chunkOffset+(chunkStop-v.start), v.chunkSize, v.cipherKey, v.isGzipped)
+			newVisibles = append(newVisibles, t)
+			// glog.V(0).Infof("visible %d [%d,%d) =2> [%d,%d)", i, v.start, v.stop, t.start, t.stop)
 		}
 		if chunkStop <= v.start || v.stop <= chunk.Offset {
 			newVisibles = append(newVisibles, v)
+			// glog.V(0).Infof("visible %d [%d,%d) =3> [%d,%d)", i, v.start, v.stop, v.start, v.stop)
 		}
 	}
 	newVisibles = append(newVisibles, newV)
@@ -219,17 +225,16 @@ func NonOverlappingVisibleIntervals(lookupFileIdFn LookupFileIdFunctionType, chu
 	chunks, _, err = ResolveChunkManifest(lookupFileIdFn, chunks)
 
 	sort.Slice(chunks, func(i, j int) bool {
-		return chunks[i].Fid.FileKey < chunks[j].Fid.FileKey
+		if chunks[i].Mtime == chunks[j].Mtime {
+			return chunks[i].Fid.FileKey < chunks[j].Fid.FileKey
+		}
+		return chunks[i].Mtime < chunks[j].Mtime // keep this to make tests run
 	})
 
-	var newVisibles []VisibleInterval
 	for _, chunk := range chunks {
 
 		// glog.V(0).Infof("merge [%d,%d)", chunk.Offset, chunk.Offset+int64(chunk.Size))
-		newVisibles = MergeIntoVisibles(visibles, newVisibles, chunk)
-		t := visibles[:0]
-		visibles = newVisibles
-		newVisibles = t
+		visibles = MergeIntoVisibles(visibles, chunk)
 
 		logPrintf("add", visibles)
 
diff --git a/weed/filesys/dir.go b/weed/filesys/dir.go
index 46f5f22ed..f20e67df1 100644
--- a/weed/filesys/dir.go
+++ b/weed/filesys/dir.go
@@ -168,7 +168,6 @@ func (dir *Dir) Create(ctx context.Context, req *fuse.CreateRequest,
 
 	node = dir.newFile(req.Name, request.Entry)
 	file := node.(*File)
-	file.isOpen++
 	fh := dir.wfs.AcquireHandle(file, req.Uid, req.Gid)
 	return file, fh, nil
 
diff --git a/weed/filesys/dirty_page.go b/weed/filesys/dirty_page.go
index 88a1a4f55..562aaff9d 100644
--- a/weed/filesys/dirty_page.go
+++ b/weed/filesys/dirty_page.go
@@ -29,9 +29,6 @@ var counter = int32(0)
 
 func (pages *ContinuousDirtyPages) AddPage(offset int64, data []byte) (chunks []*filer_pb.FileChunk, err error) {
 
-	pages.lock.Lock()
-	defer pages.lock.Unlock()
-
 	glog.V(5).Infof("%s AddPage [%d,%d) of %d bytes", pages.f.fullpath(), offset, offset+int64(len(data)), pages.f.entry.Attributes.FileSize)
 
 	if len(data) > int(pages.f.wfs.option.ChunkSizeLimit) {
@@ -82,14 +79,6 @@ func (pages *ContinuousDirtyPages) flushAndSave(offset int64, data []byte) (chun
 	return
 }
 
-func (pages *ContinuousDirtyPages) FlushToStorage() (chunks []*filer_pb.FileChunk, err error) {
-
-	pages.lock.Lock()
-	defer pages.lock.Unlock()
-
-	return pages.saveExistingPagesToStorage()
-}
-
 func (pages *ContinuousDirtyPages) saveExistingPagesToStorage() (chunks []*filer_pb.FileChunk, err error) {
 
 	var hasSavedData bool
@@ -103,7 +92,9 @@ func (pages *ContinuousDirtyPages) saveExistingPagesToStorage() (chunks []*filer
 		}
 
 		if err == nil {
-			chunks = append(chunks, chunk)
+			if chunk != nil {
+				chunks = append(chunks, chunk)
+			}
 		} else {
 			return
 		}
@@ -121,9 +112,14 @@ func (pages *ContinuousDirtyPages) saveExistingLargestPageToStorage() (chunk *fi
 	fileSize := int64(pages.f.entry.Attributes.FileSize)
 	for {
 		chunkSize := min(maxList.Size(), fileSize-maxList.Offset())
+		if chunkSize == 0 {
+			return
+		}
 		chunk, err = pages.saveToStorage(maxList.ToReader(), maxList.Offset(), chunkSize)
 		if err == nil {
-			hasSavedData = true
+			if chunk != nil {
+				hasSavedData = true
+			}
 			glog.V(4).Infof("saveToStorage %s %s [%d,%d) of %d bytes", pages.f.fullpath(), chunk.GetFileIdString(), maxList.Offset(), maxList.Offset()+chunkSize, fileSize)
 			return
 		} else {
@@ -170,10 +166,5 @@ func min(x, y int64) int64 {
 }
 
 func (pages *ContinuousDirtyPages) ReadDirtyDataAt(data []byte, startOffset int64) (maxStop int64) {
-
-	pages.lock.Lock()
-	defer pages.lock.Unlock()
-
 	return pages.intervals.ReadDataAt(data, startOffset)
-
 }
diff --git a/weed/filesys/file.go b/weed/filesys/file.go
index 43f3ddf07..f15eff780 100644
--- a/weed/filesys/file.go
+++ b/weed/filesys/file.go
@@ -87,8 +87,6 @@ func (file *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.Op
 
 	glog.V(4).Infof("file %v open %+v", file.fullpath(), req)
 
-	file.isOpen++
-
 	handle := file.wfs.AcquireHandle(file, req.Uid, req.Gid)
 
 	resp.Handle = fuse.HandleID(handle.handle)
@@ -120,7 +118,7 @@ func (file *File) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *f
 	if req.Valid.Size() {
 
 		glog.V(4).Infof("%v file setattr set size=%v chunks=%d", file.fullpath(), req.Size, len(file.entry.Chunks))
-		if req.Size < filer2.TotalSize(file.entry.Chunks) {
+		if req.Size < filer2.FileSize(file.entry) {
 			// fmt.Printf("truncate %v \n", fullPath)
 			var chunks []*filer_pb.FileChunk
 			var truncatedChunks []*filer_pb.FileChunk
@@ -252,7 +250,7 @@ func (file *File) Forget() {
 }
 
 func (file *File) maybeLoadEntry(ctx context.Context) error {
-	if file.entry == nil || file.isOpen <= 0 {
+	if file.entry == nil && file.isOpen <= 0 {
 		entry, err := file.wfs.maybeLoadEntry(file.dir.FullPath(), file.Name)
 		if err != nil {
 			glog.V(3).Infof("maybeLoadEntry file %s/%s: %v", file.dir.FullPath(), file.Name, err)
@@ -268,15 +266,14 @@ func (file *File) maybeLoadEntry(ctx context.Context) error {
 func (file *File) addChunks(chunks []*filer_pb.FileChunk) {
 
 	sort.Slice(chunks, func(i, j int) bool {
-		return chunks[i].Fid.FileKey < chunks[j].Fid.FileKey
+		if chunks[i].Mtime == chunks[j].Mtime {
+			return chunks[i].Fid.FileKey < chunks[j].Fid.FileKey
+		}
+		return chunks[i].Mtime < chunks[j].Mtime
 	})
 
-	var newVisibles []filer2.VisibleInterval
 	for _, chunk := range chunks {
-		newVisibles = filer2.MergeIntoVisibles(file.entryViewCache, newVisibles, chunk)
-		t := file.entryViewCache[:0]
-		file.entryViewCache = newVisibles
-		newVisibles = t
+		file.entryViewCache = filer2.MergeIntoVisibles(file.entryViewCache, chunk)
 	}
 
 	file.reader = nil
diff --git a/weed/filesys/filehandle.go b/weed/filesys/filehandle.go
index 94590f842..0b6aeddd2 100644
--- a/weed/filesys/filehandle.go
+++ b/weed/filesys/filehandle.go
@@ -7,6 +7,7 @@ import (
 	"math"
 	"net/http"
 	"os"
+	"sync"
 	"time"
 
 	"github.com/seaweedfs/fuse"
@@ -22,6 +23,7 @@ type FileHandle struct {
 	dirtyPages  *ContinuousDirtyPages
 	contentType string
 	handle      uint64
+	sync.RWMutex
 
 	f         *File
 	RequestId fuse.RequestID // unique ID for request
@@ -41,6 +43,7 @@ func newFileHandle(file *File, uid, gid uint32) *FileHandle {
 	if fh.f.entry != nil {
 		fh.f.entry.Attributes.FileSize = filer2.FileSize(fh.f.entry)
 	}
+
 	return fh
 }
 
@@ -55,6 +58,12 @@ var _ = fs.HandleReleaser(&FileHandle{})
 func (fh *FileHandle) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
 
 	glog.V(4).Infof("%s read fh %d: [%d,%d) size %d resp.Data cap=%d", fh.f.fullpath(), fh.handle, req.Offset, req.Offset+int64(req.Size), req.Size, cap(resp.Data))
+	fh.RLock()
+	defer fh.RUnlock()
+
+	if req.Size <= 0 {
+		return nil
+	}
 
 	buff := resp.Data[:cap(resp.Data)]
 	if req.Size > cap(resp.Data) {
@@ -65,7 +74,7 @@ func (fh *FileHandle) Read(ctx context.Context, req *fuse.ReadRequest, resp *fus
 	totalRead, err := fh.readFromChunks(buff, req.Offset)
 	if err == nil {
 		maxStop := fh.readFromDirtyPages(buff, req.Offset)
-		totalRead = max(maxStop - req.Offset, totalRead)
+		totalRead = max(maxStop-req.Offset, totalRead)
 	}
 
 	if err != nil {
@@ -77,13 +86,15 @@ func (fh *FileHandle) Read(ctx context.Context, req *fuse.ReadRequest, resp *fus
 		glog.Warningf("%s FileHandle Read %d: [%d,%d) size %d totalRead %d", fh.f.fullpath(), fh.handle, req.Offset, req.Offset+int64(req.Size), req.Size, totalRead)
 		totalRead = min(int64(len(buff)), totalRead)
 	}
-	resp.Data = buff[:totalRead]
+	// resp.Data = buff[:totalRead]
+	resp.Data = buff
 
 	return err
 }
 
 func (fh *FileHandle) readFromDirtyPages(buff []byte, startOffset int64) (maxStop int64) {
-	return fh.dirtyPages.ReadDirtyDataAt(buff, startOffset)
+	maxStop = fh.dirtyPages.ReadDirtyDataAt(buff, startOffset)
+	return
 }
 
 func (fh *FileHandle) readFromChunks(buff []byte, offset int64) (int64, error) {
@@ -127,6 +138,9 @@ func (fh *FileHandle) readFromChunks(buff []byte, offset int64) (int64, error) {
 // Write to the file handle
 func (fh *FileHandle) Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error {
 
+	fh.Lock()
+	defer fh.Unlock()
+
 	// write the request to volume servers
 	data := make([]byte, len(req.Data))
 	copy(data, req.Data)
@@ -162,19 +176,30 @@ func (fh *FileHandle) Release(ctx context.Context, req *fuse.ReleaseRequest) err
 
 	glog.V(4).Infof("Release %v fh %d", fh.f.fullpath(), fh.handle)
 
+	fh.Lock()
+	defer fh.Unlock()
+
 	fh.f.isOpen--
 
-	if fh.f.isOpen <= 0 {
+	if fh.f.isOpen < 0 {
+		glog.V(0).Infof("Release reset %s open count %d => %d", fh.f.Name, fh.f.isOpen, 0)
+		fh.f.isOpen = 0
+		return nil
+	}
+
+	if fh.f.isOpen == 0 {
 		fh.doFlush(ctx, req.Header)
 		fh.f.wfs.ReleaseHandle(fh.f.fullpath(), fuse.HandleID(fh.handle))
-		fh.f.entryViewCache = nil
-		fh.f.reader = nil
 	}
 
 	return nil
 }
 
 func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
+
+	fh.Lock()
+	defer fh.Unlock()
+
 	return fh.doFlush(ctx, req.Header)
 }
 
@@ -183,13 +208,14 @@ func (fh *FileHandle) doFlush(ctx context.Context, header fuse.Header) error {
 	// send the data to the OS
 	glog.V(4).Infof("doFlush %s fh %d %v", fh.f.fullpath(), fh.handle, header)
 
-	chunks, err := fh.dirtyPages.FlushToStorage()
+	chunks, err := fh.dirtyPages.saveExistingPagesToStorage()
 	if err != nil {
 		glog.Errorf("flush %s: %v", fh.f.fullpath(), err)
 		return fuse.EIO
 	}
 
 	if len(chunks) > 0 {
+
 		fh.f.addChunks(chunks)
 		fh.f.dirtyMetadata = true
 	}
@@ -227,18 +253,14 @@ func (fh *FileHandle) doFlush(ctx context.Context, header fuse.Header) error {
 			glog.V(4).Infof("%s chunks %d: %v [%d,%d)", fh.f.fullpath(), i, chunk.GetFileIdString(), chunk.Offset, chunk.Offset+int64(chunk.Size))
 		}
 
-		chunks, garbages := filer2.CompactFileChunks(filer2.LookupFn(fh.f.wfs), fh.f.entry.Chunks)
+		chunks, _ := filer2.CompactFileChunks(filer2.LookupFn(fh.f.wfs), fh.f.entry.Chunks)
 		chunks, manifestErr := filer2.MaybeManifestize(fh.f.wfs.saveDataAsChunk(fh.f.dir.FullPath()), chunks)
 		if manifestErr != nil {
 			// not good, but should be ok
 			glog.V(0).Infof("MaybeManifestize: %v", manifestErr)
 		}
 		fh.f.entry.Chunks = chunks
-		// fh.f.entryViewCache = nil
-
-		// special handling of one chunk md5
-		if len(chunks) == 1 {
-		}
+		fh.f.entryViewCache = nil
 
 		if err := filer_pb.CreateEntry(client, request); err != nil {
 			glog.Errorf("fh flush create %s: %v", fh.f.fullpath(), err)
@@ -247,11 +269,6 @@ func (fh *FileHandle) doFlush(ctx context.Context, header fuse.Header) error {
 
 		fh.f.wfs.metaCache.InsertEntry(context.Background(), filer2.FromPbEntry(request.Directory, request.Entry))
 
-		fh.f.wfs.deleteFileChunks(garbages)
-		for i, chunk := range garbages {
-			glog.V(4).Infof("garbage %s chunks %d: %v [%d,%d)", fh.f.fullpath(), i, chunk.GetFileIdString(), chunk.Offset, chunk.Offset+int64(chunk.Size))
-		}
-
 		return nil
 	})
 
diff --git a/weed/filesys/meta_cache/meta_cache.go b/weed/filesys/meta_cache/meta_cache.go
index 15ec0903d..c0bb75f4a 100644
--- a/weed/filesys/meta_cache/meta_cache.go
+++ b/weed/filesys/meta_cache/meta_cache.go
@@ -50,6 +50,10 @@ func openMetaStore(dbFolder string) filer2.FilerStore {
 func (mc *MetaCache) InsertEntry(ctx context.Context, entry *filer2.Entry) error {
 	mc.Lock()
 	defer mc.Unlock()
+	return mc.doInsertEntry(ctx, entry)
+}
+
+func (mc *MetaCache) doInsertEntry(ctx context.Context, entry *filer2.Entry) error {
 	filer_pb.BeforeEntrySerialization(entry.Chunks)
 	return mc.actualStore.InsertEntry(ctx, entry)
 }
diff --git a/weed/filesys/meta_cache/meta_cache_init.go b/weed/filesys/meta_cache/meta_cache_init.go
index cd98f4a7c..f5d633120 100644
--- a/weed/filesys/meta_cache/meta_cache_init.go
+++ b/weed/filesys/meta_cache/meta_cache_init.go
@@ -18,7 +18,7 @@ func EnsureVisited(mc *MetaCache, client filer_pb.FilerClient, dirPath util.Full
 
 		err = filer_pb.ReadDirAllEntries(client, dirPath, "", func(pbEntry *filer_pb.Entry, isLast bool) error {
 			entry := filer2.FromPbEntry(string(dirPath), pbEntry)
-			if err := mc.InsertEntry(context.Background(), entry); err != nil {
+			if err := mc.doInsertEntry(context.Background(), entry); err != nil {
 				glog.V(0).Infof("read %s: %v", entry.FullPath, err)
 				return err
 			}
diff --git a/weed/filesys/wfs.go b/weed/filesys/wfs.go
index f147d7548..e9ee0864b 100644
--- a/weed/filesys/wfs.go
+++ b/weed/filesys/wfs.go
@@ -118,10 +118,14 @@ func (wfs *WFS) AcquireHandle(file *File, uid, gid uint32) (fileHandle *FileHand
 	inodeId := file.fullpath().AsInode()
 	existingHandle, found := wfs.handles[inodeId]
 	if found && existingHandle != nil {
+		file.isOpen++
 		return existingHandle
 	}
 
 	fileHandle = newFileHandle(file, uid, gid)
+	file.maybeLoadEntry(context.Background())
+	file.isOpen++
+
 	wfs.handles[inodeId] = fileHandle
 	fileHandle.handle = inodeId
 
diff --git a/weed/filesys/xattr.go b/weed/filesys/xattr.go
index 091a70fa3..92e43b675 100644
--- a/weed/filesys/xattr.go
+++ b/weed/filesys/xattr.go
@@ -119,5 +119,5 @@ func (wfs *WFS) maybeLoadEntry(dir, name string) (entry *filer_pb.Entry, err err
 	if cacheErr == filer_pb.ErrNotFound {
 		return nil, fuse.ENOENT
 	}
-	return cachedEntry.ToProtoEntry(), nil
+	return cachedEntry.ToProtoEntry(), cacheErr
 }
diff --git a/weed/util/bounded_tree/bounded_tree.go b/weed/util/bounded_tree/bounded_tree.go
index 40b9c4e47..0e023c0d1 100644
--- a/weed/util/bounded_tree/bounded_tree.go
+++ b/weed/util/bounded_tree/bounded_tree.go
@@ -15,7 +15,7 @@ type Node struct {
 
 type BoundedTree struct {
 	root *Node
-	sync.Mutex
+	sync.RWMutex
 }
 
 func NewBoundedTree() *BoundedTree {
@@ -131,6 +131,9 @@ func (n *Node) getChild(childName string) *Node {
 
 func (t *BoundedTree) HasVisited(p util.FullPath) bool {
 
+	t.RLock()
+	defer t.RUnlock()
+
 	if t.root == nil {
 		return true
 	}