message: [tf.data] Fix the benchmark warm up code to make sure op that graph is not re-optimized during the timed run.
diff: @@ -75,7 +75,7 @@ class DatasetBenchmarkBase(test.Benchmark):
  if warmup:
  # Run once to warm up the session caches.
  sess.run(iterator.initializer)
  - sess.run(next_element)
  + sess.run(next_element.op)
  sess.run(iterator.initializer)
  start = time.time()
  