adjust performance of bert thor

tests/st/networks/models/bert/bert_performance/test_bert_thor.py

@@ -193,7 +193,7 @@ def train_process_bert_thor(q, device_id, epoch_size, device_num):
 @pytest.mark.platform_arm_ascend_training
 @pytest.mark.platform_x86_ascend_training
 @pytest.mark.env_single
-def test_bert_thor_mlperf_8p():
+def test_bert_thor_8p():
     """test bert thor mlperf 8p"""
     q = Queue()
     device_num = 8
@@ -234,12 +234,12 @@ def test_bert_thor_mlperf_8p():
         os.system("rm -rf " + str(i))
 
     print("End training...")
-    assert mean_cost < 78
+    assert mean_cost < 66
     assert mean_loss < 8.125
 
 
 if __name__ == '__main__':
     begin = time.time()
-    test_bert_thor_mlperf_8p()
+    test_bert_thor_8p()
     end = time.time()
     print("time span is", end - begin, flush=True)