Make sure that additional ops added by Savers to read ResourceVariables are added to the graph in a deterministic way.

For ResourceVariables (op "VarHandleOp"), ops.internal_convert_to_tensor will add new ops such as "Read_8/ReadVariableOp". If op_list is cast to a set, as before this change, then adding these new ops made graph construction non-deterministic.

PiperOrigin-RevId: 177185279

2 files changed, 16 insertions, 1 deletions

diff --git a/tensorflow/python/training/saver.py b/tensorflow/python/training/saver.py
index 5bddde1698..bd47736d4b 100644
--- a/tensorflow/python/training/saver.py
+++ b/tensorflow/python/training/saver.py
@@ -523,7 +523,10 @@ class BaseSaverBuilder(object):
     if not isinstance(op_list, (list, tuple, set)):
       raise TypeError("Variables to save should be passed in a dict or a "
                       "list: %s" % op_list)
-    op_list = set(op_list)
+    # When ResourceVariables are converted to Tensors, read ops are added to the
+    # graph. Sorting the op_list ensures that the resulting graph is always
+    # constructed in a deterministic way:
+    op_list = sorted(op_list, key=lambda x: x.name)
     names_to_saveables = {}
     # pylint: disable=protected-access
     for var in op_list:
diff --git a/tensorflow/python/training/saver_test.py b/tensorflow/python/training/saver_test.py
index 744b17dd22..98ac197204 100644
--- a/tensorflow/python/training/saver_test.py
+++ b/tensorflow/python/training/saver_test.py
@@ -164,6 +164,18 @@ class SaverTest(test.TestCase):
   def testResourceBasic(self):
     self.basicSaveRestore(resource_variable_ops.ResourceVariable)
 
+  def testResourceVariableReadOpsAddedDeterministically(self):
+    graph_defs = []
+    num_graphs = 10
+    for _ in range(num_graphs):
+      with ops_lib.Graph().as_default() as g:
+        for i in range(20):
+          resource_variable_ops.ResourceVariable(i, name="var%s" % i)
+        saver_module.Saver()
+        graph_defs.append(g.as_graph_def())
+    for i in range(num_graphs - 1):
+      self.assertEqual(graph_defs[i], graph_defs[i + 1])
+
   def testEagerBasic(self):
     with context.eager_mode():
       ckpt_prefix = os.path.join(self.get_temp_dir(), "ckpt")