def list_dependencies(self, obj):
"""Overrides a parent method to include `add_object` objects."""
extra_dependencies = self._extra_dependencies.get(obj, {})
used_names = set()
for name, dep in super(_AugmentedGraphView,
self).list_dependencies(obj):
used_names.add(name)
if name in extra_dependencies:
yield base.CheckpointableReference(name,
extra_dependencies[name])
else:
yield base.CheckpointableReference(name, dep)
for name, dep in extra_dependencies.items():
if name in used_names:
continue
yield base.CheckpointableReference(name, dep)
def _checkpoint_dependencies(self):
"""From Checkpointable. Gather graph-specific non-slot variables to save."""
current_graph_non_slot_variables = []
current_graph_key = ops.get_default_graph()._graph_key # pylint: disable=protected-access
for (name, _), variable_object in sorted(self._non_slot_dict.items(),
# Avoid comparing graphs
key=lambda item: item[0][0]):
if variable_object._graph_key == current_graph_key: # pylint: disable=protected-access
current_graph_non_slot_variables.append(
checkpointable.CheckpointableReference(
name=name, ref=variable_object))
return (super(Optimizer, self)._checkpoint_dependencies
+ current_graph_non_slot_variables)
def _lookup_dependency(self, name):
"""Create placeholder NumPy arrays for to-be-restored attributes.
Typically `_lookup_dependency` is used to check by name whether a dependency
exists. We cheat slightly by creating a checkpointable object for `name` if
we don't already have one, giving us attribute re-creation behavior when
loading a checkpoint.
Args:
name: The name of the dependency being checked.
Returns:
An existing dependency if one exists, or a new `_NumpyWrapper` placeholder
dependency (which will generally be restored immediately).
"""
value = super(NumpyState, self)._lookup_dependency(name)
if value is None:
value = _NumpyWrapper(numpy.array([]))
new_reference = base.CheckpointableReference(name=name, ref=value)
self._unconditional_checkpoint_dependencies.append(new_reference)
self._unconditional_dependency_names[name] = value
super(NumpyState, self).__setattr__(name, value)
return value
def _breadth_first_traversal(self):
"""Find shortest paths to all dependencies of self.root."""
bfs_sorted = []
to_visit = collections.deque([self.root])
path_to_root = object_identity.ObjectIdentityDictionary()
path_to_root[self.root] = ()
while to_visit:
current_checkpointable = to_visit.popleft()
if isinstance(current_checkpointable, tracking.NotCheckpointable):
raise NotImplementedError(
("The object %s does not support object-based saving. File a "
"feature request if this limitation bothers you. In the meantime, "
"you can remove the dependency on this object and save everything "
"else.")
% (current_checkpointable,))
bfs_sorted.append(current_checkpointable)
for name, dependency in self.list_dependencies(current_checkpointable):
if dependency not in path_to_root:
path_to_root[dependency] = (
path_to_root[current_checkpointable] + (
base.CheckpointableReference(name, dependency),))
to_visit.append(dependency)
return bfs_sorted, path_to_root
