diff --git a/paddle/fluid/framework/details/multi_devices_graph_builder.cc b/paddle/fluid/framework/details/multi_devices_graph_builder.cc
index 17b9c3920140557adc90c32c7e1dd635ac48eb6f..14b73b368117b4816e1aeee8bb5c73f64257c91e 100644
--- a/paddle/fluid/framework/details/multi_devices_graph_builder.cc
+++ b/paddle/fluid/framework/details/multi_devices_graph_builder.cc
@@ -84,8 +84,12 @@ void MultiDevSSAGraphBuilder::CreateOpHandleIOs(SSAGraph *result,
 std::vector<std::string> MultiDevSSAGraphBuilder::FindDistTrainSendVars(
     const ProgramDesc &program) const {
   std::vector<std::string> send_vars;
+  // since parameters are all in block 0,
+  // it's enough to only scan send ops in block 0
   for (auto *op : program.Block(0).AllOps()) {
-    if (op->Type() == "send_vars" || op->Type() == "send") {
+    // TODO(Yancey1989): use a graceful method to find send op,
+    // instead of the the hard code string
+    if (op->Type() == "send_vars") {
       auto op_vars = op->InputArgumentNames();
       send_vars.reserve(send_vars.size() +
                         std::distance(op_vars.begin(), op_vars.end()));
@@ -99,7 +103,9 @@ std::vector<std::string> MultiDevSSAGraphBuilder::FindDistTrainRecvVars(
     const ProgramDesc &program) const {
   std::vector<std::string> recv_vars;
   for (auto *op : program.Block(0).AllOps()) {
-    if (op->Type() == "recv" || op->Type() == "send") {
+    // TODO(Yancey1989): use a graceful method to find recv op,
+    // instead of the hard code string
+    if (op->Type() == "recv") {
       auto op_vars = op->OutputArgumentNames();
       recv_vars.reserve(recv_vars.size() +
                         std::distance(op_vars.begin(), op_vars.end()));
@@ -122,6 +128,9 @@ bool MultiDevSSAGraphBuilder::IsDistTrainOp(
   auto checker = [](const std::vector<std::string> &opvars,
                     const std::vector<std::string> &rpc_vars) -> bool {
     for (auto &var : opvars) {
+      // a variable name with the suffix `.block` means it's a splited
+      // variable by (DistributeTranspiler)
+      // [python/paddle/fluid/transpiler/distribute_transpiler.py]
       if (var.find(".block") != std::string::npos &&
           std::find(rpc_vars.begin(), rpc_vars.end(), var) != rpc_vars.end()) {
         return true;
@@ -130,13 +139,8 @@ bool MultiDevSSAGraphBuilder::IsDistTrainOp(
     return false;
   };
 
-  if (op.Type() == "split" || op.Type() == "split_byref" ||
-      op.Type() == "split_selected_rows") {
-    return checker(op.OutputArgumentNames(), send_vars);
-  } else if (op.Type() == "concat") {
-    return checker(op.InputArgumentNames(), recv_vars);
-  }
-
+  return checker(op.OutputArgumentNames(), send_vars) ||
+         checker(op.InputArgumentNames(), recv_vars);
   return false;
 }
 
diff --git a/paddle/fluid/operators/detail/grpc_client.cc b/paddle/fluid/operators/detail/grpc_client.cc
index f2385abed59a809e7fbea3569245af693f5842ad..51f0d2a7427a3923f038b3d85057fa0e5c8cf6a8 100644
--- a/paddle/fluid/operators/detail/grpc_client.cc
+++ b/paddle/fluid/operators/detail/grpc_client.cc
@@ -34,7 +34,7 @@ bool RPCClient::AsyncSendVariable(const std::string& ep,
   const std::string ep_val = ep;
   const std::string var_name_val = var_name;
   const framework::Scope* p_scope = &scope;
-  const auto ch = GetChannel(ep_val, ep_val + ":" + var_name_val);
+  const auto ch = GetChannel(ep_val);
 
   framework::AsyncIO([var_name_val, p_ctx, ep_val, p_scope, time_out, ch,
                       this] {
@@ -88,7 +88,7 @@ bool RPCClient::AsyncGetVariable(const std::string& ep,
   const std::string ep_val = ep;
   const std::string var_name_val = var_name;
   const framework::Scope* p_scope = &scope;
-  const auto ch = GetChannel(ep_val, ep_val + ":" + var_name_val);
+  const auto ch = GetChannel(ep_val);
 
   framework::AsyncIO([var_name_val, ep_val, p_scope, p_ctx, time_out, ch,
                       this] {
@@ -132,7 +132,7 @@ bool RPCClient::AsyncPrefetchVariable(const std::string& ep,
   const std::string in_var_name_val = in_var_name;
   const std::string out_var_name_val = out_var_name;
   const framework::Scope* p_scope = &scope;
-  const auto ch = GetChannel(ep_val, ep_val + ":" + in_var_name_val);
+  const auto ch = GetChannel(ep_val);
 
   framework::AsyncIO([in_var_name_val, out_var_name_val, ep_val, p_scope, p_ctx,
                       time_out, ch, this] {
@@ -165,7 +165,7 @@ bool RPCClient::AsyncPrefetchVariable(const std::string& ep,
 }
 
 void RPCClient::AsyncSendBatchBarrier(const std::string& ep, int64_t time_out) {
-  const auto ch = GetChannel(ep, ep);
+  const auto ch = GetChannel(ep);
 
   BatchBarrierProcessor* s = new BatchBarrierProcessor(ch);
   s->Prepare(time_out);
@@ -178,7 +178,7 @@ void RPCClient::AsyncSendBatchBarrier(const std::string& ep, int64_t time_out) {
 }
 
 void RPCClient::AsyncSendFetchBarrier(const std::string& ep, int64_t time_out) {
-  const auto ch = GetChannel(ep, ep);
+  const auto ch = GetChannel(ep);
   FetchBarrierProcessor* s = new FetchBarrierProcessor(ch);
   s->Prepare(time_out);
 
@@ -248,10 +248,9 @@ bool RPCClient::Proceed() {
   delete c;
   return true;
 }
-std::shared_ptr<grpc::Channel> RPCClient::GetChannel(const std::string& ep,
-                                                     const std::string& key) {
+std::shared_ptr<grpc::Channel> RPCClient::GetChannel(const std::string& ep) {
   std::unique_lock<std::mutex> lock(mutex_);
-  auto it = channels_.find(key);
+  auto it = channels_.find(ep);
   if (it != channels_.end()) {
     return it->second;
   }
@@ -263,7 +262,7 @@ std::shared_ptr<grpc::Channel> RPCClient::GetChannel(const std::string& ep,
 
   auto ch =
       grpc::CreateCustomChannel(ep, grpc::InsecureChannelCredentials(), args);
-  channels_[key] = ch;
+  channels_[ep] = ch;
   return ch;
 }
 
diff --git a/paddle/fluid/operators/detail/grpc_client.h b/paddle/fluid/operators/detail/grpc_client.h
index 6f8b67be3e0f4bb506840d67b6717e3a2f861ac7..e5007b509a30a5251e78e8636d53d81022dae0d3 100644
--- a/paddle/fluid/operators/detail/grpc_client.h
+++ b/paddle/fluid/operators/detail/grpc_client.h
@@ -191,8 +191,7 @@ class RPCClient {
 
  private:
   bool Proceed();
-  std::shared_ptr<grpc::Channel> GetChannel(const std::string& ep,
-                                            const std::string& key);
+  std::shared_ptr<grpc::Channel> GetChannel(const std::string& ep);
 
  private:
   grpc::CompletionQueue cq_;