diff --git a/liteflow-core/src/main/java/com/yomahub/liteflow/entity/data/DataBus.java b/liteflow-core/src/main/java/com/yomahub/liteflow/entity/data/DataBus.java
index 5e072fad4..ccc87bfe1 100644
--- a/liteflow-core/src/main/java/com/yomahub/liteflow/entity/data/DataBus.java
+++ b/liteflow-core/src/main/java/com/yomahub/liteflow/entity/data/DataBus.java
@@ -7,15 +7,18 @@
  */
 package com.yomahub.liteflow.entity.data;
 
-import java.util.concurrent.atomic.AtomicInteger;
-
 import cn.hutool.core.util.ObjectUtil;
-import com.yomahub.liteflow.exception.ConfigErrorException;
 import com.yomahub.liteflow.property.LiteflowConfig;
 import com.yomahub.liteflow.util.SpringAware;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicReferenceArray;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
 /**
  * 数据BUS，主要用来管理Slot，用以分配和回收
  * @author Bryan.Zhang
@@ -26,7 +29,9 @@ public class DataBus {
 
 	public static AtomicInteger OCCUPY_COUNT = new AtomicInteger(0);
 
-	private static Slot[] slots;
+	private static AtomicReferenceArray<Slot> SLOTS;
+
+	private static ConcurrentLinkedQueue<Integer> QUEUE;
 
 	static {
 		LiteflowConfig liteflowConfig = SpringAware.getBean(LiteflowConfig.class);
@@ -36,20 +41,22 @@ public class DataBus {
 			liteflowConfig = new LiteflowConfig();
 		}
 		int slotSize = liteflowConfig.getSlotSize();
-		slots = new Slot[slotSize];
+
+		SLOTS = new AtomicReferenceArray<>(slotSize);
+
+		QUEUE = IntStream.range(0, slotSize - 1).boxed().collect(Collectors.toCollection(ConcurrentLinkedQueue::new));
 	}
 
-	public synchronized static int offerSlot(Class<? extends Slot> slotClazz){
-		try{
-			for(int i = 0; i < slots.length; i++){
-				if(ObjectUtil.isNull(slots[i])){
-					slots[i] = slotClazz.newInstance();
-					OCCUPY_COUNT.incrementAndGet();
-					return i;
-				}
+	public synchronized static int offerSlot(Class<? extends Slot> slotClazz) {
+		try {
+			Slot slot = slotClazz.newInstance();
+			Integer slotIndex = QUEUE.poll();
+			if (ObjectUtil.isNotNull(slotIndex) && SLOTS.compareAndSet(slotIndex, null, slot)) {
+				OCCUPY_COUNT.incrementAndGet();
+				return slotIndex;
 			}
-		}catch(Exception e){
-			LOG.error("offer slot error",e);
+		} catch (Exception e) {
+			LOG.error("offer slot error", e);
 			return -1;
 		}
 		return -1;
@@ -57,13 +64,14 @@ public class DataBus {
 
 	@SuppressWarnings("unchecked")
 	public static <T extends Slot> T getSlot(int slotIndex){
-		return (T)slots[slotIndex];
+		return (T)SLOTS.get(slotIndex);
 	}
 
 	public static void releaseSlot(int slotIndex){
-		if(ObjectUtil.isNotNull(slots[slotIndex])){
-			LOG.info("[{}]:slot[{}] released",slots[slotIndex].getRequestId(),slotIndex);
-			slots[slotIndex] = null;
+		if(ObjectUtil.isNotNull(SLOTS.get(slotIndex))){
+			LOG.info("[{}]:slot[{}] released",SLOTS.get(slotIndex).getRequestId(),slotIndex);
+			SLOTS.set(slotIndex, null);
+			QUEUE.add(slotIndex);
 			OCCUPY_COUNT.decrementAndGet();
 		}else{
 			LOG.warn("slot[{}] already has been released",slotIndex);