add mountOptions.chunkSizeLimitMB, remove cmdMount.IsDebug

weed/filesys/dirty_page.go

@@ -59,7 +59,13 @@ func (pages *ContinuousDirtyPages) AddPage(ctx context.Context, offset int64, da
 			Offset: offset,
 			Data:   data,
 		})
-		return nil, nil
+
+		if pages.totalSize() >= pages.f.wfs.chunkSizeLimit {
+			chunk, err = pages.saveToStorage(ctx)
+			pages.pages = nil
+			glog.V(3).Infof("%s/%s add split [%d,%d)", pages.f.dir.Path, pages.f.Name, chunk.Offset, chunk.Offset+int64(chunk.Size))
+		}
+		return
 	}
 
 	chunk, err = pages.saveToStorage(ctx)

weed/filesys/wfs.go

@@ -13,14 +13,16 @@ type WFS struct {
 	listDirectoryEntriesCache *ccache.Cache
 	collection                string
 	replication               string
+	chunkSizeLimit            int64
 }
 
-func NewSeaweedFileSystem(filer string, collection string, replication string) *WFS {
+func NewSeaweedFileSystem(filer string, collection string, replication string, chunkSizeLimitMB int) *WFS {
 	return &WFS{
 		filer:                     filer,
 		listDirectoryEntriesCache: ccache.New(ccache.Configure().MaxSize(6000).ItemsToPrune(100)),
 		collection:                collection,
 		replication:               replication,
+		chunkSizeLimit:            int64(chunkSizeLimitMB) * 1024 * 1024,
 	}
 }