update for save way=3

Change-Id: I3b0c3753bf1dea211bd41931db19cb2550f03f6e

paddle/fluid/train/custom_trainer/feed/accessor/epoch_accessor.cc

@@ -150,6 +150,8 @@ namespace feed {
                     return true;
                 }
                 return delta_id(epoch_id) % 24 == 0;
+            case ModelSaveWay::ModelSaveTrainCheckpointBase:
+                return is_last_epoch(epoch_id);
         }
         return false;
     }
@@ -165,6 +167,7 @@ namespace feed {
             case ModelSaveWay::ModelSaveInferenceBase:
                 return _trainer_context->file_system->path_join(_inference_model_path, 
                     string::format_string("%s/base", date.c_str()));
+            case ModelSaveWay::ModelSaveTrainCheckpointBase:
             case ModelSaveWay::ModelSaveTrainCheckpoint:
                 return _trainer_context->file_system->path_join(_model_root_path, 
                     string::format_string("batch_model/%s", date_with_hour.c_str()));

paddle/fluid/train/custom_trainer/feed/process/learner_process.cc

@@ -175,7 +175,11 @@ int LearnerProcess::run() {
         {
             wait_save_model(epoch_id, ModelSaveWay::ModelSaveInferenceBase);
             environment->barrier(EnvironmentRole::WORKER); 
-            wait_save_model(epoch_id, ModelSaveWay::ModelSaveTrainCheckpoint);
+            if (epoch_accessor->is_last_epoch(epoch_id)) {
+                wait_save_model(epoch_id, ModelSaveWay::ModelSaveTrainCheckpointBase);
+            } else {
+                wait_save_model(epoch_id, ModelSaveWay::ModelSaveTrainCheckpoint);
+            }
             environment->barrier(EnvironmentRole::WORKER); 
             if (epoch_accessor->is_last_epoch(epoch_id) &&
                 environment->is_master_node(EnvironmentRole::WORKER)) {

paddle/fluid/train/custom_trainer/feed/trainer_context.h

@@ -26,7 +26,8 @@ const uint32_t SecondsPerDay = 24 * 3600;
 enum class ModelSaveWay {
     ModelSaveTrainCheckpoint = 0,
     ModelSaveInferenceDelta = 1,
-    ModelSaveInferenceBase = 2
+    ModelSaveInferenceBase = 2,
+    ModelSaveTrainCheckpointBase = 3,
 };
 
 enum class TrainerStatus {