tf.saved_model.load

Load a SavedModel from export_dir.

Used in the notebooks

Used in the guide Used in the tutorials

Signatures associated with the SavedModel are available as functions:

imported = tf.saved_model.load(path) f = imported.signatures["serving_default"] print(f(x=tf.constant([[1.]]))) 

Objects exported with tf.saved_model.save additionally have trackable objects and functions assigned to attributes:

exported = tf.train.Checkpoint(v=tf.Variable(3.)) exported.f = tf.function(     lambda x: exported.v * x,     input_signature=[tf.TensorSpec(shape=None, dtype=tf.float32)]) tf.saved_model.save(exported, path) imported = tf.saved_model.load(path) assert 3. == imported.v.numpy() assert 6. == imported.f(x=tf.constant(2.)).numpy() 

Loading Keras models

Keras models are trackable, so they can be saved to SavedModel. The object returned by tf.saved_model.load is not a Keras object (i.e. doesn't have .fit, .predict, etc. methods). A few attributes and functions are still available: .variables, .trainable_variables and .__call__.

model = tf.keras.Model(...) tf.saved_model.save(model, path) imported = tf.saved_model.load(path) outputs = imported(inputs) 

Use tf.keras.models.load_model to restore the Keras model.

Importing SavedModels from TensorFlow 1.x

1.x SavedModels APIs have a flat graph instead of tf.function objects. These SavedModels will be loaded with the following attributes:

  • .signatures: A dictionary mapping signature names to functions.
  • .prune(feeds, fetches): A method which allows you to extract functions for new subgraphs. This is equivalent to importing the SavedModel and naming feeds and fetches in a Session from TensorFlow 1.x.

    imported = tf.saved_model.load(path_to_v1_saved_model) pruned = imported.prune("x:0", "out:0") pruned(tf.ones([])) 

    See tf.compat.v1.wrap_function for details.

  • .variables: A list of imported variables.

  • .graph: The whole imported graph.

  • .restore(save_path): A function that restores variables from a checkpoint saved from tf.compat.v1.Saver.

Consuming SavedModels asynchronously

When consuming SavedModels asynchronously (the producer is a separate process), the SavedModel directory will appear before all files have been written, and tf.saved_model.load will fail if pointed at an incomplete SavedModel. Rather than checking for the directory, check for "saved_model_dir/saved_model.pb". This file is written atomically as the last tf.saved_model.save file operation.

export_dir The SavedModel directory to load from.
tags A tag or sequence of tags identifying the MetaGraph to load. Optional if the SavedModel contains a single MetaGraph, as for those exported from tf.saved_model.save.
options tf.saved_model.LoadOptions object that specifies options for loading.

A trackable object with a signatures attribute mapping from signature keys to functions. If the SavedModel was exported by tf.saved_model.save, it also points to trackable objects, functions, debug info which it has been saved.

ValueError If tags don't match a MetaGraph in the SavedModel.