diff --git a/Customize-Filer-Store.md b/Customize-Filer-Store.md
index e98985a..8be3db8 100644
--- a/Customize-Filer-Store.md
+++ b/Customize-Filer-Store.md
@@ -40,7 +40,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/cassandra"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/leveldb"
-	_ "github.com/chrislusf/seaweedfs/weed/filer2/memdb"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/mysql"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/postgres"
 	_ "github.com/chrislusf/seaweedfs/weed/filer2/redis"
diff --git a/Large-File-Handling.md b/Large-File-Handling.md
index 690761c..e8113bd 100644
--- a/Large-File-Handling.md
+++ b/Large-File-Handling.md
@@ -34,7 +34,7 @@ When reading Chunk Manifest files, the SeaweedFS will find and send the data fil
 SeaweedFS delegates the effort to the client side. The steps are:
 
 1. split large files into chunks
-1. upload each file chunk as usual, with mime type "application/octet-stream". Save the related info into ChunkInfo struct. Each chunk can be spread onto different volumes, possibly giving faster parallel access.
+1. upload each file chunk as usual. Save the related info into ChunkInfo struct. Each chunk can be spread onto different volumes, possibly giving faster parallel access.
 1. upload the manifest file with mime type "application/json", and add url parameter "cm=true". The FileId to store the manifest file is the entry point of the large file.
 
 
@@ -44,7 +44,7 @@ Usually we just append large files. Updating a specific chunk of file is almost
 
 The steps to append a large file:
 
-1. upload the new file chunks as usual, with mime type "application/octet-stream". Save the related info into ChunkInfo struct.
+1. upload the new file chunks as usual. Save the related info into ChunkInfo struct.
 1. update the updated manifest file with mime type "application/json", and add url parameter "cm=true".
 
 ## Notes