title: CancelledError: Loop execution was cancelled
body: <p>I was doing some regression analysis using google colabs and until yesterday everything was working fine but today suddenly I'm getting following error. I don't know why the training is getting stopped in the middle. </p>
  
  <p>Following is the output from training:</p>
  
  <pre><code> SA1 
  
  
  Fold:  1
  
  
  
  WARNING:tensorflow:From /usr/local/lib/python3.6/dist-packages/tensorflow/python/framework/op_def_library.py:263: colocate_with (from tensorflow.python.framework.ops) is deprecated and will be removed in a future version.
  Instructions for updating:
  Colocations handled automatically by placer.
  WARNING:tensorflow:From &lt;ipython-input-8-18bba4154a19&gt;:225: DatasetV1.make_initializable_iterator (from tensorflow.python.data.ops.dataset_ops) is deprecated and will be removed in a future version.
  Instructions for updating:
  Use `for ... in dataset:` to iterate over a dataset. If using `tf.estimator`, return the `Dataset` object directly from your input function. As a last resort, you can use `tf.compat.v1.data.make_initializable_iterator(dataset)`.
  WARNING:tensorflow:From &lt;ipython-input-9-d355616e5022&gt;:238: calling dropout (from tensorflow.python.ops.nn_ops) with keep_prob is deprecated and will be removed in a future version.
  Instructions for updating:
  Please use `rate` instead of `keep_prob`. Rate should be set to `rate = 1 - keep_prob`.
  WARNING:tensorflow:From &lt;ipython-input-9-d355616e5022&gt;:347: dense (from tensorflow.python.layers.core) is deprecated and will be removed in a future version.
  Instructions for updating:
  Use keras.layers.dense instead.
  WARNING:tensorflow:From &lt;ipython-input-9-d355616e5022&gt;:160: to_float (from tensorflow.python.ops.math_ops) is deprecated and will be removed in a future version.
  Instructions for updating:
  Use tf.cast instead.
  WARNING:tensorflow:From /usr/local/lib/python3.6/dist-packages/tensorflow/python/training/saver.py:1266: checkpoint_exists (from tensorflow.python.training.checkpoint_management) is deprecated and will be removed in a future version.
  Instructions for updating:
  Use standard file APIs to check for files with this prefix.
  INFO:tensorflow:Restoring parameters from data/vars/SA1/feeder.cpt
  Training the model with He ...
  0 MAPE: 9500.299072265625
  100 MAPE: 948.7984657287598
  200 MAPE: 494.5207118988037
  300 MAPE: 254.67548370361328
  400 MAPE: 134.2471480369568
  500 MAPE: 81.28451704978943
  600 MAPE: 52.48984694480896
  
  ---------------------------------------------------------------------------
  
  CancelledError                            Traceback (most recent call last)
  
  /usr/local/lib/python3.6/dist-packages/tensorflow/python/client/session.py in _do_call(self, fn, *args)
     1333     try:
  -&gt; 1334       return fn(*args)
     1335     except errors.OpError as e:
  
  /usr/local/lib/python3.6/dist-packages/tensorflow/python/client/session.py in _run_fn(feed_dict, fetch_list, target_list, options, run_metadata)
     1318       return self._call_tf_sessionrun(
  -&gt; 1319           options, feed_dict, fetch_list, target_list, run_metadata)
     1320 
  
      /usr/local/lib/python3.6/dist-packages/tensorflow/python/client/session.py in _call_tf_sessionrun(self, options, feed_dict, fetch_list, target_list, run_metadata)
         1406         self._session, options, feed_dict, fetch_list, target_list,
      -&gt; 1407         run_metadata)
         1408 
  CancelledError: Loop execution was cancelled.
       [[{{node while/LoopCond}}]]
  
  
  During handling of the above exception, another exception occurred:
  </code></pre>