1.672640157855923 not greater than 2

Traceback (most recent call last):
  File "/home/jenkins/workspace/spark-master-test-sbt-hadoop-2.7/python/pyspark/mllib/tests/test_streaming_algorithms.py", line 503, in test_train_prediction
    self._eventually(condition)
  File "/home/jenkins/workspace/spark-master-test-sbt-hadoop-2.7/python/pyspark/mllib/tests/test_streaming_algorithms.py", line 69, in _eventually
    lastValue = condition()
  File "/home/jenkins/workspace/spark-master-test-sbt-hadoop-2.7/python/pyspark/mllib/tests/test_streaming_algorithms.py", line 498, in condition
    self.assertGreater(errors[1] - errors[-1], 2)
AssertionError: 1.672640157855923 not greater than 2