diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
index b5c6cd567..02bbbdd3e 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
@@ -132,7 +132,7 @@ public Session getSession(String userName, String password, boolean reconnect)
         SyncConnection connection = null;
         try {
             connection = getConnection();
-            AuthResult authResult = connection.authenticate(userName, password);
+            AuthResult authResult = connection.authenticate(userName, password,Integer.MAX_VALUE);
             return new Session(connection, authResult, this, reconnect);
         } catch (Exception e) {
             // if get the connection succeeded, but authenticate failed,
diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/Session.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/Session.java
index 35709d558..bc6a92ecc 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/Session.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/Session.java
@@ -61,23 +61,36 @@ public Session(SyncConnection connection,
      * @return The ResultSet
      */
     public synchronized ResultSet execute(String stmt) throws IOErrorException {
+        return execute(stmt,0);
+    }
+
+
+    /**
+     * Execute the nGql sentence.
+     *
+     * @param stmt The nGql sentence.
+     *             such as insert ngql `INSERT VERTEX person(name) VALUES "Tom":("Tom");`
+     * @param timeout temporary setting timeout
+     * @return The ResultSet
+     */
+    public synchronized ResultSet execute(String stmt,int timeout) throws IOErrorException {
         if (connection == null) {
             throw new IOErrorException(IOErrorException.E_CONNECT_BROKEN,
-                "The session was released, couldn't use again.");
+                    "The session was released, couldn't use again.");
         }
 
         if (connectionIsBroken.get() && retryConnect) {
             if (retryConnect()) {
-                ExecutionResponse resp = connection.execute(sessionID, stmt);
+                ExecutionResponse resp = connection.execute(sessionID, stmt,timeout);
                 return new ResultSet(resp, timezoneOffset);
             } else {
                 throw new IOErrorException(IOErrorException.E_ALL_BROKEN,
-                    "All servers are broken.");
+                        "All servers are broken.");
             }
         }
 
         try {
-            ExecutionResponse resp = connection.execute(sessionID, stmt);
+            ExecutionResponse resp = connection.execute(sessionID, stmt,timeout);
             return new ResultSet(resp, timezoneOffset);
         } catch (IOErrorException ie) {
             if (ie.getType() == IOErrorException.E_CONNECT_BROKEN) {
@@ -87,7 +100,7 @@ public synchronized ResultSet execute(String stmt) throws IOErrorException {
                 if (retryConnect) {
                     if (retryConnect()) {
                         connectionIsBroken.set(false);
-                        ExecutionResponse resp = connection.execute(sessionID, stmt);
+                        ExecutionResponse resp = connection.execute(sessionID, stmt,timeout);
                         return new ResultSet(resp, timezoneOffset);
                     } else {
                         connectionIsBroken.set(true);
@@ -100,6 +113,7 @@ public synchronized ResultSet execute(String stmt) throws IOErrorException {
         }
     }
 
+
     /**
      * Check current connection is ok
      *
diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/SessionsManager.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/SessionsManager.java
index 059199209..2cd66bb7f 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/SessionsManager.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/SessionsManager.java
@@ -38,6 +38,14 @@ private void checkConfig() {
         }
     }
 
+    /**
+     *
+     * @return canUseBitSet size
+     */
+    public synchronized int getCanUseSize(){
+        return canUseBitSet.length();
+    }
+
     /**
      * getSessionWrapper: return a SessionWrapper from sessionManager,
      * the SessionWrapper couldn't use by multi-thread
@@ -66,7 +74,7 @@ public synchronized SessionWrapper getSessionWrapper() throws RuntimeException {
         try {
             Session session = pool.getSession(
                 config.getUserName(), config.getPassword(), config.getReconnect());
-            ResultSet resultSet = session.execute("USE " + config.getSpaceName());
+            ResultSet resultSet = session.execute("USE " + config.getSpaceName(),Integer.MAX_VALUE);
             if (!resultSet.isSucceeded()) {
                 throw new RuntimeException(
                     "Switch space `"
diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/SyncConnection.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/SyncConnection.java
index e1ccdebcd..cb6f36e0a 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/SyncConnection.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/SyncConnection.java
@@ -22,7 +22,7 @@
 import com.vesoft.nebula.graph.GraphService;
 
 public class SyncConnection extends Connection {
-    protected TTransport transport = null;
+    protected TSocket transport = null;
     protected TProtocol protocol = null;
     private GraphService.Client client = null;
     private int timeout = 0;
@@ -58,9 +58,21 @@ public void reopen() throws IOErrorException {
         open(serverAddr, timeout);
     }
 
-    public AuthResult authenticate(String user, String password)
+    /**
+     *
+     * @param user
+     * @param password
+     * @param timeout temporary setting timeout
+     * @return
+     * @throws AuthFailedException
+     * @throws IOErrorException
+     */
+    public AuthResult authenticate(String user, String password,int timeout)
         throws AuthFailedException, IOErrorException {
         try {
+            if (timeout>0) {
+                transport.setTimeout(timeout);
+            }
             AuthResponse resp = client.authenticate(user.getBytes(), password.getBytes());
             if (resp.error_code != ErrorCode.SUCCEEDED) {
                 if (resp.error_msg != null) {
@@ -86,12 +98,34 @@ public AuthResult authenticate(String user, String password)
                 }
             }
             throw new AuthFailedException(String.format("Authenticate failed: %s", e.getMessage()));
+        }finally {
+            if (timeout>0) {
+                transport.setTimeout(this.timeout);
+            }
         }
     }
 
-    public ExecutionResponse execute(long sessionID, String stmt)
+
+    public AuthResult authenticate(String user, String password)
+            throws AuthFailedException, IOErrorException {
+        return authenticate(user,password,0);
+    }
+
+
+    /**
+     *
+     * @param sessionID
+     * @param stmt
+     * @param timeout temporary setting timeout
+     * @return
+     * @throws IOErrorException
+     */
+    public ExecutionResponse execute(long sessionID, String stmt,int timeout)
             throws IOErrorException {
         try {
+            if (timeout>0) {
+                transport.setTimeout(timeout);
+            }
             return client.execute(sessionID, stmt.getBytes());
         } catch (TException e) {
             if (e instanceof TTransportException) {
@@ -101,15 +135,25 @@ public ExecutionResponse execute(long sessionID, String stmt)
                 } else if (te.getType() == TTransportException.NOT_OPEN) {
                     throw new IOErrorException(IOErrorException.E_NO_OPEN, te.getMessage());
                 } else if (te.getType() == TTransportException.TIMED_OUT
-                    || te.getMessage().contains("Read timed out")) {
+                        || te.getMessage().contains("Read timed out")) {
                     reopen();
                     throw new IOErrorException(IOErrorException.E_TIME_OUT, te.getMessage());
                 }
             }
             throw new IOErrorException(IOErrorException.E_UNKNOWN, e.getMessage());
+        }finally {
+            if (timeout>0) {
+                transport.setTimeout(this.timeout);
+            }
         }
     }
 
+
+    public ExecutionResponse execute(long sessionID, String stmt)
+            throws IOErrorException {
+        return execute(sessionID,stmt,0);
+    }
+
     public void signout(long sessionId) {
         client.signout(sessionId);
     }