fix pserver and prefetch rpc

paddle/fluid/operators/distributed/grpc_client.cc

@@ -169,6 +169,7 @@ VarHandlePtr GRPCClient::AsyncPrefetchVar(const std::string& ep,
                                           const framework::Scope& scope,
                                           const std::string& in_var_name,
                                           const std::string& out_var_name,
+                                          const std::string& table_name,
                                           int64_t time_out) {
   const platform::DeviceContext* p_ctx = &ctx;
   const std::string ep_val = ep;
@@ -184,11 +185,12 @@ VarHandlePtr GRPCClient::AsyncPrefetchVar(const std::string& ep,
   s->Prepare(h, time_out);
 
   framework::AsyncIO([in_var_name_val, out_var_name_val, ep_val, p_scope, p_ctx,
-                      s, method, h, this] {
+                      s, method, h, table_name, this] {
     auto* var = p_scope->FindVar(in_var_name_val);
 
     ::grpc::ByteBuffer req;
-    SerializeToByteBuffer(in_var_name_val, var, *p_ctx, &req, out_var_name_val);
+    SerializeToByteBuffer(in_var_name_val, var, *p_ctx, &req, out_var_name_val,
+                          0, table_name);
 
     VLOG(30) << s->GetVarHandlePtr()->String() << " begin";
 

paddle/fluid/operators/distributed/grpc_client.h

@@ -194,6 +194,7 @@ class GRPCClient : public RPCClient {
                                 const framework::Scope& scope,
                                 const std::string& in_var_name,
                                 const std::string& out_var_name,
+                                const std::string& table_name = "",
                                 int64_t time_out = FLAGS_rpc_deadline) override;
 
   VarHandlePtr AsyncSendBatchBarrier(

paddle/fluid/operators/distributed/grpc_serde.cc

@@ -42,7 +42,8 @@ static void SerializeDestroyCallback(void* payload) {
 void SerializeToByteBuffer(const std::string& name, framework::Variable* var,
                            const platform::DeviceContext& ctx,
                            ::grpc::ByteBuffer* msg, const std::string& out_name,
-                           const int trainer_id) {
+                           const int trainer_id,
+                           const std::string& table_name) {
   platform::RecordRPCEvent record_event("serial", &ctx);
   VarMsg request;
   TensorPayload* payload = nullptr;
@@ -63,6 +64,9 @@ void SerializeToByteBuffer(const std::string& name, framework::Variable* var,
   if (!out_name.empty()) {
     request.set_out_varname(out_name);
   }
+  if (!table_name.empty()) {
+    request.set_table_name(table_name);
+  }
   if (var->IsType<framework::LoDTensor>()) {
     request.set_type(::sendrecv::LOD_TENSOR);
     payload = new TensorPayload(GetTensorPayload(var, ctx, &request));

paddle/fluid/operators/distributed/grpc_serde.h

@@ -39,7 +39,8 @@ void SerializeToByteBuffer(const std::string& name, framework::Variable* var,
                            const platform::DeviceContext& ctx,
                            ::grpc::ByteBuffer* msg,
                            const std::string& out_varname = std::string(),
-                           const int trainer_id = 0);
+                           const int trainer_id = 0,
+                           const std::string& table_name = std::string());
 
 void DeserializeFromByteBuffer(const ::grpc::ByteBuffer& msg,
                                const platform::DeviceContext& ctx,

paddle/fluid/operators/distributed/parameter_prefetch.cc

@@ -84,7 +84,7 @@ inline void SplitIdsIntoMultipleVarsBySection(
     const std::vector<int64_t>& height_section,
     const std::vector<std::vector<int64_t>>& splited_ids,
     framework::Scope* scope) {
-  PADDLE_ENFORCE_EQ(in_var_names.size(), height_section.size() + 1, "");
+  PADDLE_ENFORCE_EQ(in_var_names.size(), height_section.size(), "");
 
   auto place = platform::CPUPlace();
 
@@ -184,7 +184,8 @@ void prefetch(const std::string& id_name, const std::string& out_name,
       VLOG(30) << "sending " << in_var_names[i] << " to " << epmap[i]
                << " to get " << out_var_names[i] << " back";
       rets.push_back(rpc_client->AsyncPrefetchVar(
-          epmap[i], ctx, local_scope, in_var_names[i], out_var_names[i]));
+          epmap[i], ctx, local_scope, in_var_names[i], out_var_names[i],
+          table_name));
     } else {
       VLOG(30) << "don't send no-initialied variable: " << out_var_names[i];
     }

paddle/fluid/operators/distributed/request_handler_impl.cc

@@ -120,12 +120,13 @@ bool RequestPrefetchHandler::Handle(const std::string& varname,
                                     const std::string& table_name) {
   VLOG(40) << "RequestPrefetchHandler " << varname;
 
-  auto var_desc = program_->Block(0).FindVar(out_var_name);
-  InitializeVariable(*outvar, var_desc->GetType());
   if (table_name.empty()) {
+    auto var_desc = program_->Block(0).FindVar(out_var_name);
+    InitializeVariable(*outvar, var_desc->GetType());
     executor_->RunPreparedContext(
         (*prefetch_var_name_to_prepared_ctx_)[varname].get(), scope);
   } else {
+    (*outvar)->GetMutable<framework::LoDTensor>();
     auto lookup_table_op =
         BuildLookupTableOp(table_name, varname, out_var_name);
     paddle::platform::CPUPlace cpu_place;

paddle/fluid/operators/distributed/rpc_client.h

@@ -48,7 +48,7 @@ class RPCClient {
   virtual VarHandlePtr AsyncPrefetchVar(
       const std::string& ep, const platform::DeviceContext& ctx,
       const framework::Scope& scope, const std::string& in_var_name,
-      const std::string& out_var_name,
+      const std::string& out_var_name, const std::string& table_name = "",
       int64_t time_out = FLAGS_rpc_deadline) = 0;
 
   virtual VarHandlePtr AsyncSendBatchBarrier(