I'm currently dealing with the challenge to serve my tensorflow models in a scalable way. As far as I know the recommended solution is to use the standard TensorFlow ModelServer. Common requirements are pretty well handled by this - but I want more. I want to decrease the transfered amount of data by parsing a parameter like "limit" to define the top n logits + probabilites to return.
During my research I identified the following solutions:
1) Create a more advanced SignatureDef during model building.
2) Customize the basic tensorflow/serving project with the mentioned functionality.
3) Serve the model with the standard Tensorflow Modelserver and build a postprocessing service to restructure resp. filter the result in the predefined way.
Can someone more experienced than me go into some details regarding my question? - codesnippets or links would be awesome.
Thanks in advance.
Your solution number 3,
"Serve the model with the standard Tensorflow Modelserver and build a postprocessing service to restructure resp. filter the result in the predefined way."
should be the best one.
Links and Code Snippets: If we consider the example of MNIST using TF Serving, the link for Saved Model is, https://github.com/tensorflow/serving/blob/87e32bb386f156fe208df633c1a7f489b57464e1/tensorflow_serving/example/mnist_saved_model.py,
and the link for Client code is https://github.com/tensorflow/serving/blob/87e32bb386f156fe208df633c1a7f489b57464e1/tensorflow_serving/example/mnist_client.py.
If we want values of top-n predictions, we can tweak the code of the function, _create_rpc_callback
in the Client file as shown below.
def _create_rpc_callback(label, result_counter):
"""Creates RPC callback function.
Args:
label: The correct label for the predicted example.
result_counter: Counter for the prediction result.
Returns:
The callback function.
"""
def _callback(result_future):
"""Callback function.
Calculates the statistics for the prediction result.
Args:
result_future: Result future of the RPC.
"""
exception = result_future.exception()
if exception:
result_counter.inc_error()
print(exception)
else:
sys.stdout.write('.')
sys.stdout.flush()
response = numpy.array(result_future.result().outputs['scores'].float_val)
print('Top 4 responses = ', response[0:4])
The print
statement in the last line will print Top-4 Predictions.