diff --git a/NewLife.RocketMQ/Common/ILoadBalance.cs b/NewLife.RocketMQ/Common/ILoadBalance.cs
new file mode 100644
index 0000000..7ec91ce
--- /dev/null
+++ b/NewLife.RocketMQ/Common/ILoadBalance.cs
@@ -0,0 +1,20 @@
+using System;
+
+namespace NewLife.RocketMQ.Common
+{
+    /// <summary>负载均衡接口</summary>
+    public interface ILoadBalance
+    {
+        /// <summary>已就绪</summary>
+        Boolean Ready { get; set; }
+
+        /// <summary>设置每个选项的权重数据</summary>
+        /// <param name="weights"></param>
+        void Set(Int32[] weights);
+
+        /// <summary>根据权重选择，并返回该项是第几次选中</summary>
+        /// <param name="times">第几次选中</param>
+        /// <returns></returns>
+        Int32 Get(out Int32 times);
+    }
+}
\ No newline at end of file
diff --git a/NewLife.RocketMQ/Common/WeightRoundRobin.cs b/NewLife.RocketMQ/Common/WeightRoundRobin.cs
index 6623544..4e35684 100644
--- a/NewLife.RocketMQ/Common/WeightRoundRobin.cs
+++ b/NewLife.RocketMQ/Common/WeightRoundRobin.cs
@@ -4,37 +4,45 @@
 namespace NewLife.RocketMQ.Common
 {
     /// <summary>带权重负载均衡算法</summary>
-    public class WeightRoundRobin
+    public class WeightRoundRobin : ILoadBalance
     {
         #region 属性
+        /// <summary>已就绪</summary>
+        public Boolean Ready { get; set; }
+
         /// <summary>权重集合</summary>
-        public Int32[] Weights { get; set; }
+        public Int32[] Weights { get; private set; }
 
         /// <summary>最小权重</summary>
-        private readonly Int32 minWeight;
+        private Int32 minWeight;
 
         /// <summary>状态值</summary>
-        private readonly Int32[] _states;
+        private Int32[] _states;
 
         /// <summary>次数</summary>
-        private readonly Int32[] _times;
+        private Int32[] _times;
         #endregion
 
-        #region 构造
-        /// <summary>实例化</summary>
-        public WeightRoundRobin(Int32[] weights)
+        #region 方法
+        /// <summary>设置每个选项的权重数据</summary>
+        /// <param name="weights"></param>
+        public void Set(Int32[] weights)
         {
+            if (weights == null) throw new ArgumentNullException(nameof(weights));
+            if (Weights != null && Weights.SequenceEqual(weights)) return;
+
             Weights = weights;
 
             minWeight = weights.Min();
 
             _states = new Int32[weights.Length];
             _times = new Int32[weights.Length];
+
+            Ready = true;
         }
-        #endregion
 
-        #region 方法
         /// <summary>根据权重选择，并返回该项是第几次选中</summary>
+        /// <param name="times">第几次选中</param>
         /// <returns></returns>
         public Int32 Get(out Int32 times)
         {
diff --git a/NewLife.RocketMQ/MqBase.cs b/NewLife.RocketMQ/MqBase.cs
index 8c63322..294b52e 100644
--- a/NewLife.RocketMQ/MqBase.cs
+++ b/NewLife.RocketMQ/MqBase.cs
@@ -166,7 +166,7 @@ public virtual Boolean Start()
         #endregion
 
         #region 收发信息
-        private readonly ConcurrentDictionary<String, BrokerClient> _Brokers = new ConcurrentDictionary<String, BrokerClient>();
+        private readonly ConcurrentDictionary<String, BrokerClient> _Brokers = new();
         /// <summary>获取代理客户端</summary>
         /// <param name="name"></param>
         /// <returns></returns>
diff --git a/NewLife.RocketMQ/NewLife.RocketMQ.csproj b/NewLife.RocketMQ/NewLife.RocketMQ.csproj
index 49195fb..46f4b03 100644
--- a/NewLife.RocketMQ/NewLife.RocketMQ.csproj
+++ b/NewLife.RocketMQ/NewLife.RocketMQ.csproj
@@ -7,8 +7,8 @@
     <Description>纯托管轻量级RocketMQ客户端，支持发布消息、消费消息、负载均衡等核心功能！</Description>
     <Company>新生命开发团队</Company>
     <Copyright>©2002-2021 NewLife</Copyright>
-    <Version>1.5.2021.0304</Version>
-    <FileVersion>1.5.2021.0304</FileVersion>
+    <Version>1.5.2021.0403</Version>
+    <FileVersion>1.5.2021.0403</FileVersion>
     <AssemblyVersion>1.5.*</AssemblyVersion>
     <Deterministic>false</Deterministic>
     <OutputPath>..\Bin</OutputPath>
@@ -24,7 +24,7 @@
     <RepositoryUrl>https://github.com/NewLifeX/NewLife.RocketMQ</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
     <PackageTags>新生命团队;X组件;NewLife;$(AssemblyName)</PackageTags>
-    <PackageReleaseNotes>每次消费完成后，实时提交消费进度</PackageReleaseNotes>
+    <PackageReleaseNotes>生产者公开负载均衡接口，同时支持重载选择队列；消费者支持解压缩超过4k的大消息</PackageReleaseNotes>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
     <AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>
     <PublishRepositoryUrl>true</PublishRepositoryUrl>
@@ -65,7 +65,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="NewLife.Core" Version="8.10.2021.316-beta2" />
+    <PackageReference Include="NewLife.Core" Version="8.10.2021.403-rc3" />
   </ItemGroup>
 
 </Project>
diff --git a/NewLife.RocketMQ/Producer.cs b/NewLife.RocketMQ/Producer.cs
index eeb671d..b585ac8 100644
--- a/NewLife.RocketMQ/Producer.cs
+++ b/NewLife.RocketMQ/Producer.cs
@@ -13,6 +13,9 @@ namespace NewLife.RocketMQ
     public class Producer : MqBase
     {
         #region 属性
+        /// <summary>负载均衡。发布消息时，分发到各个队列的负载均衡算法，默认使用带权重的轮询</summary>
+        public ILoadBalance LoadBalance { get; set; }
+
         //public Int32 DefaultTopicQueueNums { get; set; } = 4;
 
         //public Int32 SendMsgTimeout { get; set; } = 3_000;
@@ -35,12 +38,15 @@ public override Boolean Start()
         {
             if (!base.Start()) return false;
 
+            if (LoadBalance == null) LoadBalance = new WeightRoundRobin();
+
             if (_NameServer != null)
             {
                 _NameServer.OnBrokerChange += (s, e) =>
                 {
                     _brokers = null;
-                    _robin = null;
+                    //_robin = null;
+                    LoadBalance.Ready = false;
                 };
             }
 
@@ -49,7 +55,7 @@ public override Boolean Start()
         #endregion
 
         #region 发送消息
-        private static readonly DateTime _dt1970 = new DateTime(1970, 1, 1);
+        private static readonly DateTime _dt1970 = new(1970, 1, 1);
         /// <summary>发送消息</summary>
         /// <param name="msg"></param>
         /// <param name="timeout"></param>
@@ -137,12 +143,13 @@ public virtual SendResult Publish(Object body, String tags, String keys, Int32 t
 
         #region 选择Broker队列
         private IList<BrokerInfo> _brokers;
-        private WeightRoundRobin _robin;
+        //private WeightRoundRobin _robin;
         /// <summary>选择队列</summary>
         /// <returns></returns>
-        public MessageQueue SelectQueue()
+        public virtual MessageQueue SelectQueue()
         {
-            if (_robin == null)
+            var lb = LoadBalance;
+            if (!lb.Ready)
             {
                 var list = Brokers.Where(e => e.Permission.HasFlag(Permissions.Write) && e.WriteQueueNums > 0).ToList();
                 if (list.Count == 0) return null;
@@ -151,11 +158,12 @@ public MessageQueue SelectQueue()
                 if (total <= 0) return null;
 
                 _brokers = list;
-                _robin = new WeightRoundRobin(list.Select(e => e.WriteQueueNums).ToArray());
+                //lb = new WeightRoundRobin();
+                lb.Set(list.Select(e => e.WriteQueueNums).ToArray());
             }
 
             // 构造排序列表。希望能够均摊到各Broker
-            var idx = _robin.Get(out var times);
+            var idx = lb.Get(out var times);
             var bk = _brokers[idx];
             return new MessageQueue { BrokerName = bk.Name, QueueId = (times - 1) % bk.WriteQueueNums };
         }
diff --git a/Test/Program.cs b/Test/Program.cs
index df220be..a6e0ea7 100644
--- a/Test/Program.cs
+++ b/Test/Program.cs
@@ -143,7 +143,8 @@ static void Test3()
             Console.WriteLine(list[1].Equals(list2[1]));
             Console.WriteLine(list2.SequenceEqual(list));
 
-            var robin = new WeightRoundRobin(list.Select(e => e.WriteQueueNums).ToArray());
+            var robin = new WeightRoundRobin();
+            robin.Set(list.Select(e => e.WriteQueueNums).ToArray());
             var count = list.Sum(e => e.WriteQueueNums);
             for (var i = 0; i < count; i++)
             {
diff --git a/Test/Test.csproj b/Test/Test.csproj
index b3326f3..2100aaf 100644
--- a/Test/Test.csproj
+++ b/Test/Test.csproj
@@ -7,7 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="NewLife.Core" Version="8.10.2021.316-beta2" />
+    <PackageReference Include="NewLife.Core" Version="8.10.2021.403-rc3" />
   </ItemGroup>
 
   <ItemGroup>