diff --git a/mindspore/ccsrc/pipeline/pynative/grad/grad.cc b/mindspore/ccsrc/pipeline/pynative/grad/grad.cc
index f480d6ce380..e1bc8022260 100644
--- a/mindspore/ccsrc/pipeline/pynative/grad/grad.cc
+++ b/mindspore/ccsrc/pipeline/pynative/grad/grad.cc
@@ -780,6 +780,7 @@ void GradExecutor::CheckNeedCompileGraph(const InputArgsInfoPtr &input_args_info
     {
       py::gil_scoped_acquire acquire;
       EraseTopCellFromTopCellList(pre_top_cell);
+      pre_top_cell->ClearDeviceMemory();
     }
     already_run_top_cell_[already_top_cell_id] = new_top_cell;
     new_top_cell->set_force_top_cell_compile(false);
diff --git a/mindspore/ccsrc/runtime/pynative/async/async_queue.cc b/mindspore/ccsrc/runtime/pynative/async/async_queue.cc
index 24f45a7f4ff..b692a118d3a 100644
--- a/mindspore/ccsrc/runtime/pynative/async/async_queue.cc
+++ b/mindspore/ccsrc/runtime/pynative/async/async_queue.cc
@@ -40,17 +40,10 @@ void AsyncQueue::WorkerLoop() {
 
   while (true) {
     std::shared_ptr<AsyncTask> task;
-    bool task_empty = false;
     {
       std::unique_lock<std::mutex> lock(task_mutex_);
-      task_empty = tasks_.empty();
-      if (!task_empty) {
-        task = tasks_.front();
-      }
-    }
-    if (task_empty) {
-      std::this_thread::yield();
-      continue;
+      task_cond_var_.wait(lock, [this]() { return !tasks_.empty(); });
+      task = tasks_.front();
     }
 
     MS_LOG(DEBUG) << "Get task";