diff --git a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/NotifyListener.java b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/NotifyListener.java
index e410a8dffe905c69707b6d4f72d6c6f4c59d3eb0..758059327a4848c8e037624eb29096dde2d9791d 100644
--- a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/NotifyListener.java
+++ b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/NotifyListener.java
@@ -31,8 +31,9 @@ public interface NotifyListener {
      * 当收到服务变更通知时触发。
      * 
      * 通知需处理契约：<br>
-     * 1. 总是以服务接口为维度全量通知，即不会通知一个服务的部分数据，用户不需要对比上一次通知结果。<br>
-     * 2. 允许不同类型的数据分开通知，比如：providers, consumers, routes, overrides，允许只通知其中一种类型，但该类型的数据必须是全量的，不是增量的。<br>
+     * 1. 总是以服务接口和数据类型为维度全量通知，即不会通知一个服务的同类型的部分数据，用户不需要对比上一次通知结果。<br>
+     * 2. 订阅时的第一次通知，必须是一个服务的所有类型数据的全量通知。<br>
+     * 2. 中途变更时，允许不同类型的数据分开通知，比如：providers, consumers, routes, overrides，允许只通知其中一种类型，但该类型的数据必须是全量的，不是增量的。<br>
      * 3. 如果一种类型的数据为空，需通知一个empty协议并带category参数的标识性URL数据。<br>
      * 4. 通知者(即注册中心实现)需保证通知的顺序，比如：单线程推送，队列串行化，带版本对比。<br>
      * 
diff --git a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/RegistryService.java b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/RegistryService.java
index 0191cfaaf7624457fb09f063cea916854ce4b86e..e5719074ba4e4b6534ecc70bea935ac1775eb077 100644
--- a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/RegistryService.java
+++ b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/RegistryService.java
@@ -63,6 +63,7 @@ public interface RegistryService {
      * 4. 并且查询条件允许星号通配，订阅所有接口的所有分组的所有版本，或：interface=*&group=*&version=*&classifier=*<br>
      * 5. 当注册中心重启，网络抖动，需自动恢复订阅请求。<br>
      * 6. 允许URI相同但参数不同的URL并存，不能覆盖。<br>
+     * 7. 必须阻塞订阅过程，等第一次通知完后再返回。<br>
      * 
      * @param url 订阅条件，不允许为空，如：consumer://10.20.153.10/com.alibaba.foo.BarService?version=1.0.0&application=kylin
      * @param listener 变更事件监听器，不允许为空
diff --git a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/support/AbstractRegistry.java b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/support/AbstractRegistry.java
index f5446a9d7965c37ab2c8808fa42f25ffb7486536..434105e6bdface340923d5f4d0c02f1748d0da9a 100644
--- a/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/support/AbstractRegistry.java
+++ b/dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/support/AbstractRegistry.java
@@ -30,10 +30,13 @@ import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicLong;
 
 import com.alibaba.dubbo.common.Constants;
@@ -260,36 +263,28 @@ public abstract class AbstractRegistry implements Registry {
         }
         return null;
     }
-
+    
     public List<URL> lookup(URL url) {
-        List<URL> urls= new ArrayList<URL>();
         Map<String, List<URL>> notifiedUrls = getNotified().get(url);
         if (notifiedUrls != null && notifiedUrls.size() > 0) {
-            for (List<URL> values : notifiedUrls.values()) {
-                urls.addAll(values);
+            List<URL> result = new ArrayList<URL>();
+            for (List<URL> urls : notifiedUrls.values()) {
+                result.addAll(urls);
             }
-        }
-        if (urls == null || urls.size() == 0) {
-            List<URL> cacheUrls = getCacheUrls(url);
-            if (cacheUrls != null && cacheUrls.size() > 0) {
-                urls.addAll(cacheUrls);
-            }
-        }
-        if (urls == null || urls.size() == 0) {
-            for (URL u: getRegistered()) {
-                if (UrlUtils.isMatch(url, u)) {
-                    urls.add(u);
-                }
-            }
-        }
-        if (Constants.ANY_VALUE.equals(url.getServiceInterface())) {
-            for (URL u: getSubscribed().keySet()) {
-                if (UrlUtils.isMatch(url, u)) {
-                    urls.add(u);
+            return result;
+        } else {
+            final BlockingQueue<List<URL>> queue = new LinkedBlockingQueue<List<URL>>(1);
+            subscribe(url, new NotifyListener() {
+                public void notify(List<URL> urls) {
+                    queue.offer(urls);
                 }
+            });
+            try {
+                return queue.poll(getUrl().getParameter(Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT), TimeUnit.MILLISECONDS);
+            } catch (InterruptedException e) {
+                return null;
             }
         }
-        return urls;
     }
 
     public void register(URL url) {