diff --git a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowPusher.java b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowPusher.java
index eef60a1..0f56c54 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowPusher.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowPusher.java
@@ -95,19 +95,20 @@
 		
 	}
 	
-	private Map<IOFSwitch,SwitchQueue> queues
-		= new HashMap<IOFSwitch,SwitchQueue>();
-	
 	private OFMessageDamper messageDamper;
 
 	private FloodlightContext context = null;
 	private BasicFactory factory = null;
-	private Thread thread = null;
+	private Map<Long, FlowPusherProcess> threadMap = null;
 	
-	private boolean isStopped = false;
-	private boolean isMsgAdded = false;
+	private int number_thread = 1;
 	
 	private class FlowPusherProcess implements Runnable {
+		private Map<IOFSwitch,SwitchQueue> queues
+		= new HashMap<IOFSwitch,SwitchQueue>();
+		
+		private boolean isStopped = false;
+		private boolean isMsgAdded = false;
 		
 		@Override
 		public void run() {
@@ -145,17 +146,17 @@
 								// if need to send, call IOFSwitch#write()
 								try {
 									messageDamper.write(sw, msg, context);
-									size += msg.getLength();
 									log.debug("Pusher sends message : {}", msg);
+									size += msg.getLength();
 								} catch (IOException e) {
 									// TODO Auto-generated catch block
 									e.printStackTrace();
 								}
 							}
+							sw.flush();
 							queue.logSentData(current_time, size);
 						}
 					}
-					sw.flush();
 				}
 				
 				// sleep while all queues are empty
@@ -180,6 +181,14 @@
 		}
 	}
 	
+	public FlowPusher() {
+		
+	}
+	
+	public FlowPusher(int number_thread) {
+		this.number_thread = number_thread;
+	}
+	
 	public void init(FloodlightContext context, BasicFactory factory, OFMessageDamper damper) {
 		this.context = context;
 		this.factory = factory;
@@ -193,6 +202,7 @@
 				    OFMESSAGE_DAMPER_TIMEOUT);
 		}
 	}
+	
 	/**
 	 * Begin processing queue.
 	 */
@@ -202,8 +212,14 @@
 			return;
 		}
 		
-		thread = new Thread(new FlowPusherProcess());
-		thread.start();
+		threadMap = new HashMap<Long,FlowPusherProcess>();
+		for (long i = 0; i < number_thread; ++i) {
+			FlowPusherProcess runnable = new FlowPusherProcess();
+			threadMap.put(i, runnable);
+			
+			Thread thread = new Thread(runnable);
+			thread.start();
+		}
 	}
 	
 	/**
@@ -260,8 +276,14 @@
 	 * End processing queue and exit thread.
 	 */
 	public void stop() {
-		if (thread != null && thread.isAlive()) {
-			isStopped = true;
+		if (threadMap == null) {
+			return;
+		}
+		
+		for (FlowPusherProcess runnable : threadMap.values()) {
+			if (! runnable.isStopped) {
+				runnable.isStopped = true;
+			}
 		}
 	}
 	
@@ -282,22 +304,23 @@
 	 * @param msg
 	 */
 	public boolean add(IOFSwitch sw, OFMessage msg) {
-		SwitchQueue queue = getQueue(sw);
+		FlowPusherProcess proc = getProcess(sw);
+		SwitchQueue queue = proc.queues.get(sw);
+
 		if (queue == null) {
 			queue = new SwitchQueue();
 			queue.state = QueueState.READY;
-			synchronized (queues) {
-				queues.put(sw, queue);
+			synchronized (proc) {
+				proc.queues.put(sw, queue);
 			}
 		}
 		
-		log.debug("Message is pushed : {}", msg);
-		
 		synchronized (queue) {
 			queue.add(msg);
+			log.debug("Message is pushed : {}", msg);
 		}
 		
-		isMsgAdded = true;
+		proc.isMsgAdded = true;
 		
 		return true;
 	}
@@ -929,6 +952,17 @@
 			return null;
 		}
 		
-		return queues.get(sw);
+		return getProcess(sw).queues.get(sw);
+	}
+	
+	private long getHash(IOFSwitch sw) {
+		// TODO should consider equalization algorithm
+		return sw.getId() % number_thread;
+	}
+	
+	private FlowPusherProcess getProcess(IOFSwitch sw) {
+		long hash = getHash(sw);
+		
+		return threadMap.get(hash);
 	}
 }