title: Does tensorflow.data.experimental.CsvDataset read from the file over and over?
body: <p>I am struggling with long training times with tf.data.Dataset, and am beginning to wonder if reading the CSV file may be a bottleneck. Does <a href="https://www.tensorflow.org/api_docs/python/tf/data/experimental/CsvDataset" rel="nofollow noreferrer">tensorflow.data.experimental.CsvDataset</a> read from the file over and over?</p>
  
  <p>I consider trying to first import the whole dataset and put it in a numpy array, and then create a new <a href="https://www.tensorflow.org/api_docs/python/tf/data/Dataset#from_tensors" rel="nofollow noreferrer">TF Dataset from tensors</a>. But such a change will take time, and I don't want to waste time if SO could have told me beforehand that it makes no difference.</p>