Using graph_metrics.py with a saved graph - tensorflow

Question

I want to view statistics of my model by saving my graph to a file then running graph_metrics.py.
I have tried a few different things to write the file, my best effort is:
tf.train.write_graph( session.graph_def, ".", "my_graph", as_text=True )
But here's what happens:
$ python ./util/graph_metrics.py --noinput_binary --graph my_graph
Traceback (most recent call last):
File "./util/graph_metrics.py", line 137, in <module>
tf.app.run()
File ".virtualenv/local/lib/python2.7/site-packages/tensorflow/python/platform/app.py", line 30, in run
sys.exit(main(sys.argv))
File "./util/graph_metrics.py", line 85, in main
FLAGS.batch_size)
File "./util/graph_metrics.py", line 109, in calculate_graph_metrics
input_tensor = sess.graph.get_tensor_by_name(input_layer)
File ".virtualenv/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2531, in get_tensor_by_name
return self.as_graph_element(name, allow_tensor=True, allow_operation=False)
File ".virtualenv/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2385, in as_graph_element
return self._as_graph_element_locked(obj, allow_tensor, allow_operation)
File ".virtualenv/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2427, in _as_graph_element_locked
"graph." % (repr(name), repr(op_name)))
KeyError: "The name 'Mul:0' refers to a Tensor which does not exist. The operation, 'Mul', does not exist in the graph."
Is there a complete working example of saving a graph, then analyzing it with graph_metrics.py?
This process seems to involve a magic incantation that I haven't yet discovered.

Answer 1

The error you're hitting is because you need to specify the name of your own input node with --input_layer= (it just defaults to Mul:0 because that's what we use in one of our Inception models):
https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/tools/graph_metrics.py#L51
The graph_metrics script is still very much a work in progress unfortunately, and you may hit problems with shape inference, but hopefully this should get you past the initial hurdle.