diff --git a/src/main/java/com/alibaba/wasp/executor/EventHandler.java b/src/main/java/com/alibaba/wasp/executor/EventHandler.java
index a22307d..c62fc54 100644
--- a/src/main/java/com/alibaba/wasp/executor/EventHandler.java
+++ b/src/main/java/com/alibaba/wasp/executor/EventHandler.java
@@ -56,6 +56,7 @@
 public abstract class EventHandler implements Runnable, Comparable<Runnable> {
   private static final Log LOG = LogFactory.getLog(EventHandler.class);
 
+  private static volatile boolean hasExecuted;
   // type of event this object represents
   protected EventType eventType;
 
@@ -192,6 +193,7 @@ public EventHandler(Server server, EventType eventType) {
   public void run() {
     Span chunk = Trace.startSpan(Thread.currentThread().getName(), parent,
         Sampler.ALWAYS);
+    hasExecuted = true;
     try {
       if (getListener() != null)
         getListener().beforeProcess(this);
@@ -205,6 +207,10 @@ public void run() {
     }
   }
 
+  public static boolean getExecutedStatus() {
+    return hasExecuted;
+  }
+
   /**
    * This method is the main processing loop to be implemented by the various
    * subclasses.
diff --git a/src/test/java/com/alibaba/wasp/executor/TestExecutorService.java b/src/test/java/com/alibaba/wasp/executor/TestExecutorService.java
index 10915d7..eeeafe4 100644
--- a/src/test/java/com/alibaba/wasp/executor/TestExecutorService.java
+++ b/src/test/java/com/alibaba/wasp/executor/TestExecutorService.java
@@ -79,6 +79,9 @@ public void testExecutorService() throws Exception {
     int tries = 0;
     while (counter.get() < maxThreads && tries < maxTries) {
       LOG.info("Waiting for all event handlers to start...");
+      while (!EventHandler.getExecutedStatus()) { 
+        Thread.yield(); 
+      }
       Thread.sleep(sleepInterval);
       tries++;
     }