diff --git a/tests/python_client/testcases/test_e2e_20.py b/tests/python_client/testcases/test_e2e_20.py
index dc4c43e5da..24069a3c4f 100644
--- a/tests/python_client/testcases/test_e2e_20.py
+++ b/tests/python_client/testcases/test_e2e_20.py
@@ -1,4 +1,4 @@
-import datetime
+import time
 import pytest
 
 from base.client_base import TestcaseBase
@@ -17,35 +17,35 @@ class TestE2e(TestcaseBase):
         from utils.util_log import test_log as log
         # create
         name = cf.gen_unique_str(prefix)
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         collection_w = self.init_collection_wrap(name=name)
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert create: {tt}")
         assert collection_w.name == name
 
         # insert
         data = cf.gen_default_list_data()
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         _, res = collection_w.insert(data)
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert insert: {tt}")
         assert res
 
         # flush
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         assert collection_w.num_entities == len(data[0])
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert flush: {tt}")
 
         # search
         collection_w.load()
         search_vectors = cf.gen_vectors(1, ct.default_dim)
         search_params = {"metric_type": "L2", "params": {"nprobe": 16}}
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         res_1, _ = collection_w.search(data=search_vectors,
                                        anns_field=ct.default_float_vec_field_name,
                                        param=search_params, limit=1)
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert search: {tt}")
         assert len(res_1) == 1
         collection_w.release()
@@ -55,31 +55,31 @@ class TestE2e(TestcaseBase):
         collection_w.insert(d)
         assert collection_w.num_entities == len(data[0]) + 2000
         _index_params = {"index_type": "IVF_SQ8", "params": {"nlist": 64}, "metric_type": "L2"}
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         index, _ = collection_w.create_index(field_name=ct.default_float_vec_field_name,
                                              index_params=_index_params,
                                              name=cf.gen_unique_str())
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert index: {tt}")
         assert len(collection_w.indexes) == 1
 
         # search
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         collection_w.load()
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert load: {tt}")
         search_vectors = cf.gen_vectors(1, ct.default_dim)
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         res_1, _ = collection_w.search(data=search_vectors,
                                        anns_field=ct.default_float_vec_field_name,
                                        param=search_params, limit=1)
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert search: {tt}")
 
         # query
         term_expr = f'{ct.default_int64_field_name} in [3001,4001,4999,2999]'
-        t0 = datetime.datetime.now()
+        t0 = time.time()
         res, _ = collection_w.query(term_expr)
-        tt = datetime.datetime.now() - t0
+        tt = time.time() - t0
         log.debug(f"assert query: {tt}")
         # assert len(res) == 4