Enable dist se resnext (#12365)

* enable dist se resnext

* small batch size

python/paddle/fluid/tests/unittests/dist_se_resnext.py

@@ -278,7 +278,7 @@ class DistSeResneXt2x2:
 
     def run_trainer(self, place, endpoints, trainer_id, trainers, is_dist=True):
         test_program, avg_cost, train_reader, test_reader, batch_acc, predict = get_model(
-            batch_size=20)
+            batch_size=2)
         if is_dist:
             t = get_transpiler(trainer_id,
                                fluid.default_main_program(), endpoints,
@@ -294,11 +294,7 @@ class DistSeResneXt2x2:
         strategy.num_threads = 1
         strategy.allow_op_delay = False
         exe = fluid.ParallelExecutor(
-            True,
-            loss_name=avg_cost.name,
-            exec_strategy=strategy,
-            num_trainers=trainers,
-            trainer_id=trainer_id)
+            True, loss_name=avg_cost.name, exec_strategy=strategy)
 
         feed_var_list = [
             var for var in trainer_prog.global_block().vars.itervalues()

python/paddle/fluid/tests/unittests/test_dist_se_resnext.py

@@ -56,7 +56,7 @@ class TestDistSeResneXt2x2(unittest.TestCase):
             except os.error:
                 retry_times -= 1
 
-    def non_test_with_place(self):
+    def test_with_place(self):
         # *ATTENTION* THIS TEST NEEDS AT LEAST 2GPUS TO RUN
         required_envs = {
             "PATH": os.getenv("PATH"),