diff --git a/pom.xml b/pom.xml
index 01f053e05..0ede7c5e0 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
     <artifactId>liteflow</artifactId>
     <packaging>jar</packaging>
     <modelVersion>4.0.0</modelVersion>
-    <version>1.2.8</version>
+    <version>1.2.9</version>
 
     <properties>
     	<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
diff --git a/src/main/java/com/thebeastshop/liteflow/core/FlowExecutor.java b/src/main/java/com/thebeastshop/liteflow/core/FlowExecutor.java
index 72a3a031e..a10e217b8 100644
--- a/src/main/java/com/thebeastshop/liteflow/core/FlowExecutor.java
+++ b/src/main/java/com/thebeastshop/liteflow/core/FlowExecutor.java
@@ -14,6 +14,7 @@ import java.util.List;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
+import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -94,6 +95,10 @@ public class FlowExecutor {
 				throw new NoAvailableSlotException("the slot is not exist");
 			}
 			
+			if(StringUtils.isBlank(slot.getRequestId())) {
+				slot.generateRequestId();
+			}
+			
 			if(!isInnerChain) {
 				slot.setRequestData(param);
 			}else {
diff --git a/src/main/java/com/thebeastshop/liteflow/entity/data/AbsSlot.java b/src/main/java/com/thebeastshop/liteflow/entity/data/AbsSlot.java
index 32a695b88..cb471e792 100644
--- a/src/main/java/com/thebeastshop/liteflow/entity/data/AbsSlot.java
+++ b/src/main/java/com/thebeastshop/liteflow/entity/data/AbsSlot.java
@@ -36,6 +36,8 @@ public abstract class AbsSlot implements Slot{
 	
 	private final String CHAIN_REQ_PREFIX = "chain_req_";
 	
+	private final String REQUEST_ID = "req_id";
+	
 	private Deque<CmpStep> executeSteps = new ArrayDeque<CmpStep>();
 	
 	protected ConcurrentHashMap<String, Object> dataMap = new ConcurrentHashMap<String, Object>();
@@ -117,4 +119,14 @@ public abstract class AbsSlot implements Slot{
 		}
 		LOG.info(str.toString());
 	}
+	
+	@Override
+	public void generateRequestId() {
+		dataMap.put(REQUEST_ID, System.nanoTime());
+	}
+	
+	@Override
+	public String getRequestId() {
+		return (String)dataMap.get(REQUEST_ID);
+	}
 }
diff --git a/src/main/java/com/thebeastshop/liteflow/entity/data/Slot.java b/src/main/java/com/thebeastshop/liteflow/entity/data/Slot.java
index 3e0d706f8..a7163e9a2 100644
--- a/src/main/java/com/thebeastshop/liteflow/entity/data/Slot.java
+++ b/src/main/java/com/thebeastshop/liteflow/entity/data/Slot.java
@@ -41,4 +41,8 @@ public interface Slot {
 	public void addStep(CmpStep step);
 	
 	public void printStep();
+	
+	public void generateRequestId();
+	
+	public String getRequestId();
 }