add RequestCheckpointNotify in grpc

paddle/fluid/operators/detail/grpc_server.cc

@@ -247,6 +247,9 @@ void AsyncGRPCServer::StartServer() {
       std::bind(&AsyncGRPCServer::TryToRegisterNewOne, this,
                 std::placeholders::_1, std::placeholders::_2);
 
+  LOG(INFO) << "Server StartServer on "
+            << "TryToRegisterNewOne bind finished";
+
   for (auto& t : rpc_call_map_) {
     auto& rpc_name = t.first;
     auto& cq = rpc_cq_[rpc_name];
@@ -255,6 +258,8 @@ void AsyncGRPCServer::StartServer() {
 
     reqs.reserve(kRequestBufSize);
 
+    LOG(INFO) << "TryToRegisterNewOne on RPC NAME: " << rpc_name << "I: " << i;
+
     for (int i = 0; i < kRequestBufSize; i++) {
       TryToRegisterNewOne(rpc_name, i);
     }

paddle/fluid/operators/detail/request_handler.h

@@ -43,8 +43,8 @@ constexpr char kRequestCheckpoint[] = "RequestCheckpoint";
 #define FETCH_BARRIER_MESSAGE "FETCH_BARRIER@RECV"
 #define COMPLETE_MESSAGE "COMPLETE@RECV"
 
-#define CHECKPOINT_SAVE_MESSAGE "SAVE"
-#define CHECKPOINT_LOAD_MESSAGE "LOAD"
+#define CHECKPOINT_SAVE_MESSAGE "SAVE@CHECKPOINTNOTIFY"
+#define CHECKPOINT_LOAD_MESSAGE "LOAD@CHECKPOINTNOTIFY"
 
 class RPCServer;