# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from __future__ import print_function import os import six import pickle import warnings from paddle.fluid import core from paddle.fluid.compiler import BuildStrategy, CompiledProgram, ExecutionStrategy from paddle.fluid.data_feeder import check_type from paddle.fluid.dygraph.base import program_desc_tracing_guard, switch_to_static_graph from paddle.fluid.dygraph.dygraph_to_static.program_translator import ProgramTranslator, FunctionSpec from paddle.fluid.dygraph.layers import Layer from paddle.fluid.executor import Executor, scope_guard from paddle.fluid.framework import Program, Block, Variable, ParamBase, _dygraph_tracer, dygraph_only, _dygraph_guard, _current_expected_place, in_dygraph_mode from paddle.fluid.wrapped_decorator import wrap_decorator from paddle.fluid.dygraph.io import TranslatedLayer, VARIABLE_FILENAME, EXTRA_VAR_INFO_FILENAME __all__ = ['TracedLayer', 'declarative', 'dygraph_to_static_func'] def create_program_from_desc(program_desc): program = Program() program.desc = program_desc program.blocks = [Block(program, 0)] program._sync_with_cpp() return program def _extract_vars(inputs, result_list): if isinstance(inputs, Variable): result_list.append(inputs) elif isinstance(inputs, (list, tuple)): for var in inputs: _extract_vars(var, result_list) else: raise TypeError( "The type of 'each element of inputs' in fluid.dygraph.jit.TracedLayer.trace must be fluid.Variable, but received {}.". format(type(inputs))) def extract_vars(inputs): result_list = [] _extract_vars(inputs, result_list) return result_list def _dygraph_to_static_func_(dygraph_func): """ Converts imperative dygraph APIs into declarative function APIs. Decorator @dygraph_to_static_func only converts imperative dygraph APIs into declarative net-building APIs, which means it doesn't return immediate digital result as imperative mode. Users should handle Program and Executor by themselves. Note: This decorator is NOT our recommended way to transform imperative function to declarative function. We will remove this decorator after we finalize cleaning up code. Args: dygraph_func (callable): callable imperative function. Returns: Callable: converting imperative dygraph APIs into declarative net-building APIs. Examples: .. code-block:: python import paddle.fluid as fluid import numpy as np from paddle.fluid.dygraph.jit import dygraph_to_static_func @dygraph_to_static_func def func(x): if fluid.layers.mean(x) < 0: x_v = x - 1 else: x_v = x + 1 return x_v x = fluid.layers.fill_constant(shape=[3, 3], value=0, dtype='float64') x_v = func(x) exe = fluid.Executor(fluid.CPUPlace()) out = exe.run(fetch_list=[x_v]) print(out[0]) # [[1. 1. 1.] # [1. 1. 1.] # [1. 1. 1.]] """ # TODO: remove this decorator after we finalize training API def __impl__(*args, **kwargs): program_translator = ProgramTranslator() if in_dygraph_mode() or not program_translator.enable_declarative: warnings.warn( "The decorator 'dygraph_to_static_func' doesn't work in " "dygraph mode or set ProgramTranslator.enable to False. " "We will just return dygraph output.") return dygraph_func(*args, **kwargs) static_func = program_translator.get_func(dygraph_func) return static_func(*args, **kwargs) return __impl__ dygraph_to_static_func = wrap_decorator(_dygraph_to_static_func_) def _declarative_(dygraph_func): """ Converts imperative dygraph APIs into declarative function APIs. Decorator @declarative handles the Program and Executor of static mode and returns the result as a dygraph VarBase. Args: dygraph_func (callable): callable imperative function. Returns: VarBase: containing the numerical result. Examples: .. code-block:: python import paddle.fluid as fluid import numpy as np from paddle.fluid.dygraph.jit import declarative @declarative def func(x): x = fluid.dygraph.to_variable(x) if fluid.layers.mean(x) < 0: x_v = x - 1 else: x_v = x + 1 return x_v x = np.ones([1, 2]) x_v = func(x) print(x_v.numpy()) # [[2. 2.]] """ def __impl__(*args, **kwargs): program_translator = ProgramTranslator() if not program_translator.enable_declarative: warnings.warn( "The decorator 'declarative' doesn't work when setting ProgramTranslator.enable=False. " "We will just return dygraph output.") return dygraph_func(*args, **kwargs) return program_translator.get_output(dygraph_func, *args, **kwargs) return __impl__ declarative = wrap_decorator(_declarative_) class SaveLoadConfig(object): """ The additional configuration options may be used in function :ref:`api_imperative_jit_save` that save :ref:`api_imperative_TranslatedLayer` or used in function :ref:`api_imperative_jit_load` that load :ref:`api_imperative_TranslatedLayer` . Examples: 1. Using ``SaveLoadConfig`` when saving model .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative class SimpleNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(SimpleNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): y = self._linear(x) z = self._linear(y) return z # enable dygraph mode fluid.enable_dygraph() # train model net = SimpleNet(8, 8) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) for i in range(10): out = net(x) loss = fluid.layers.mean(out) loss.backward() adam.minimize(loss) net.clear_gradients() # use SaveLoadconfig when saving model model_path = "simplenet.example.model" configs = fluid.dygraph.jit.SaveLoadConfig() configs.model_filename = "__simplenet__" fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[x], configs=configs) 2. Using ``SaveLoadConfig`` when loading model .. code-block:: python import numpy as np import paddle.fluid as fluid # enable dygraph mode fluid.enable_dygraph() # use SaveLoadconfig when loading model model_path = "simplenet.example.model" configs = fluid.dygraph.jit.SaveLoadConfig() configs.model_filename = "__simplenet__" infer_net = fluid.dygraph.jit.load(model_path, configs=configs) # inference x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) pred = infer_net(x) """ def __init__(self): self._output_spec = None self._model_filename = None self._params_filename = None self._separate_params = False # NOTE: Users rarely use following configs, so these configs are not open to users, # reducing user learning costs, but we retain the configuration capabilities # If True, programs are modified to only support direct inference deployment. # Otherwise,more information will be stored for flexible optimization and re-training. # Currently, only True is supported self._export_for_deployment = True # If True, It will save inference program only, and do not save params of Program self._program_only = False @property def output_spec(self): """ Selects the output targets of the saved model ( :ref:`api_imperative_TranslatedLayer` ). By default, all return variables of original Layer's forward function are kept as the output of the saved TranslatedLayer. The ``output_spec`` type should be list[Variable]. If the provided ``output_spec`` list is not all output variables, the saved model will be pruned according to the given ``output_spec`` list. .. note:: The ``output_spec`` is only used when saving model. Examples: .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative class SimpleNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(SimpleNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): y = self._linear(x) z = self._linear(y) loss = fluid.layers.mean(z) return z, loss # enable dygraph mode fluid.enable_dygraph() # train model net = SimpleNet(8, 8) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) for i in range(10): out, loss = net(x) loss.backward() adam.minimize(loss) net.clear_gradients() # use SaveLoadconfig.output_spec model_path = "simplenet.example.model.output_spec" configs = fluid.dygraph.jit.SaveLoadConfig() # only keep the predicted output in saved model, diccard loss configs.output_spec = [out] fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[x], configs=configs) infer_net = fluid.dygraph.jit.load(model_path, configs=configs) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) # only have the predicted output pred = infer_net(x) """ return self._output_spec @output_spec.setter def output_spec(self, spec): if not isinstance(spec, list): raise TypeError( "The SaveLoadConfig.output_spec should be 'list', but received input type is %s." % type(input)) for var in spec: if not isinstance(var, core.VarBase): raise TypeError( "The element in SaveLoadConfig.output_spec list should be 'Variable', but received element's type is %s." % type(var)) self._output_spec = spec @property def model_filename(self): """ The name of file to save the translated program of target Layer. Default filename is :code:`__model__` . Exampels: .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative class SimpleNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(SimpleNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): y = self._linear(x) z = self._linear(y) return z # enable dygraph mode fluid.enable_dygraph() # train model net = SimpleNet(8, 8) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) for i in range(10): out = net(x) loss = fluid.layers.mean(out) loss.backward() adam.minimize(loss) net.clear_gradients() model_path = "simplenet.example.model.model_filename" configs = fluid.dygraph.jit.SaveLoadConfig() configs.model_filename = "__simplenet__" # saving with configs.model_filename fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[x], configs=configs) # [result] the saved model directory contains: # __simplenet__ __variables__ __variables.info__ # loading with configs.model_filename infer_net = fluid.dygraph.jit.load(model_path, configs=configs) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) pred = infer_net(x) """ return self._model_filename @model_filename.setter def model_filename(self, filename): if not isinstance(filename, six.string_types): raise TypeError( "The SaveLoadConfig.model_filename should be str, but received input's type is %s." % type(filename)) if len(filename) == 0: raise ValueError( "The SaveLoadConfig.model_filename is empty string.") self._model_filename = filename @property def params_filename(self): """ The name of file to save all persistable variables in target Layer. Default file name is :code:`__variables__` . Exampels: .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative class SimpleNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(SimpleNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): y = self._linear(x) z = self._linear(y) return z # enable dygraph mode fluid.enable_dygraph() # train model net = SimpleNet(8, 8) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) for i in range(10): out = net(x) loss = fluid.layers.mean(out) loss.backward() adam.minimize(loss) net.clear_gradients() model_path = "simplenet.example.model.params_filename" configs = fluid.dygraph.jit.SaveLoadConfig() configs.params_filename = "__params__" # saving with configs.params_filename fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[x], configs=configs) # [result] the saved model directory contains: # __model__ __params__ __variables.info__ # loading with configs.params_filename infer_net = fluid.dygraph.jit.load(model_path, configs=configs) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) pred = infer_net(x) """ return self._params_filename @params_filename.setter def params_filename(self, filename): if not isinstance(filename, six.string_types): raise TypeError( "The SaveLoadConfig.params_filename should be str, but received input's type is %s." % type(filename)) if len(filename) == 0: raise ValueError( "The SaveLoadConfig.params_filename is empty string.") self._params_filename = filename # NOTE: [why not use params_filename=None control params saved separately] # The new save interface does not recommend parameters to be saved separately. # Here, the concept should be separated as clearly as possible. # Setting params_filename=None only means that the saved file name is set # and without any other meaning. New separate_params control for file saved # separately can makes the concept clearer. @property def separate_params(self): """ Configure whether to save the Layer parameters as separete files. (In order to be compatible with the behavior of :ref:`api_fluid_io_save_inference_model` ) If True, each parameter will be saved to a file separately, the file name is the parameter name, and the SaveLoadConfig.params_filename configuration will not take effect. Default False. Examples: .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative class SimpleNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(SimpleNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): y = self._linear(x) z = self._linear(y) return z # enable dygraph mode fluid.enable_dygraph() # train model net = SimpleNet(8, 8) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) for i in range(10): out = net(x) loss = fluid.layers.mean(out) loss.backward() adam.minimize(loss) net.clear_gradients() model_path = "simplenet.example.model.separate_params" configs = fluid.dygraph.jit.SaveLoadConfig() configs.separate_params = True # saving with configs.separate_params fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[x], configs=configs) # [result] the saved model directory contains: # linear_0.b_0 linear_0.w_0 __model__ __variables.info__ # loading with configs.params_filename infer_net = fluid.dygraph.jit.load(model_path, configs=configs) x = fluid.dygraph.to_variable(np.random.random((4, 8)).astype('float32')) pred = infer_net(x) """ return self._separate_params @separate_params.setter def separate_params(self, value): if not isinstance(value, bool): raise TypeError( "The SaveLoadConfig.separate_params should be bool value, but received input's type is %s." % type(value)) self._separate_params = value @switch_to_static_graph def save(layer, model_path, input_spec=None, configs=None): """ Saves input declarative Layer as :ref:`api_imperative_TranslatedLayer` format model, which can be used for inference or fine-tuning after loading. It will save the translated program and all related persistable variables of input declarative Layer to given ``model_path``. The default saved translated program file name is ``__model__``, and the default saved persistable variables file name is ``__variables__``, and it also saved some additional variable description information to file ``__varibales.info__``, these additional information is used in fine-tuning. The saved model can be loaded by follow APIs: - :ref:`api_imperative_jit_load` - :ref:`api_fluid_io_load_inference_model` (need pass ``params_filename='__variables__'``) - Other C++ inference APIs Args: layer (Layer): the Layer to be saved. The Layer should be decorated by `@declarative`. model_path (str): the directory to save the model. input_spec (list[Varibale], optional): Describes the input of the saved model. It is the example inputs that will be passed to saved TranslatedLayer's forward function. If None, all input variables of the original Layer's forward function would be the inputs of the saved model. Default None. configs (SaveLoadConfig, optional): :ref:`api_imperative_jit_saveLoadConfig` object that specifies additional configuration options. Default None. Returns: None Examples: .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative BATCH_SIZE = 32 BATCH_NUM = 20 def random_batch_reader(): def _get_random_images_and_labels(image_shape, label_shape): image = np.random.random(size=image_shape).astype('float32') label = np.random.random(size=label_shape).astype('int64') return image, label def __reader__(): for _ in range(BATCH_NUM): batch_image, batch_label = _get_random_images_and_labels( [BATCH_SIZE, 784], [BATCH_SIZE, 1]) yield batch_image, batch_label return __reader__ class LinearNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(LinearNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): return self._linear(x) # enable dygraph mode fluid.enable_dygraph() # create network net = LinearNet(784, 1) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) # create data loader train_loader = fluid.io.DataLoader.from_generator(capacity=5) train_loader.set_batch_generator(random_batch_reader()) # train for data in train_loader(): img, label = data label.stop_gradient = True cost = net(img) loss = fluid.layers.cross_entropy(cost, label) avg_loss = fluid.layers.mean(loss) avg_loss.backward() adam.minimize(avg_loss) net.clear_gradients() # save model model_path = "linear.example.model" fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[img]) """ def get_inout_spec(all_vars, target_vars, return_name=False): result_list = [] valid_var_dict = {} valid_vars = [var for var in all_vars if isinstance(var, Variable)] for var in valid_vars: valid_var_dict[var.name] = var if target_vars: for i, var in enumerate(target_vars): # check target var whether exists if var.name not in valid_var_dict: raise RuntimeError( "The variable to feed/fetch are not exist.") result_list.append(valid_var_dict[var.name]) else: result_list = valid_vars if return_name: result_list = [var.name for var in result_list] return result_list # 1. input check prog_translator = ProgramTranslator() if not prog_translator.enable: raise RuntimeError( "The paddle.imperative.jit.save doesn't work when setting ProgramTranslator.enable=False." ) if not isinstance(layer, Layer): raise TypeError( "The input layer of paddle.imperative.jit.save should be 'Layer', but received layer type is %s." % type(layer)) if configs is None: configs = SaveLoadConfig() if input_spec is not None: if not isinstance(input_spec, list): raise TypeError( "The input input_spec should be 'list', but received input_spec's type is %s." % type(input_spec)) for var in input_spec: if not isinstance(var, core.VarBase): raise TypeError( "The element in input_spec list should be 'Variable', but received element's type is %s." % type(var)) # 2. get program of declarative Layer.forward prog_cache = prog_translator.get_program_cache() # make dummy args & kwargs, to get excepted FunctionSpec layer_func = FunctionSpec(type(layer).forward, [layer], {}) concrete_program, _ = prog_cache.get_program(layer_func) # NOTE: we maintain the mapping of variable name to # structured name, the buffer variable (non-persistable) # saved to inference program may not need by dygraph Layer, # we only record the state_dict variable's structured name state_names_dict = dict() for structured_name, var in layer.state_dict().items(): state_names_dict[var.name] = structured_name # 3. share parameters from Layer to scope & record var info scope = core.Scope() extra_var_info = dict() for param_or_buffer in concrete_program.parameters: # share to scope param_or_buffer_tensor = scope.var(param_or_buffer.name).get_tensor() src_tensor = param_or_buffer.value().get_tensor() param_or_buffer_tensor._share_data_with(src_tensor) # record var info extra_info_dict = dict() if param_or_buffer.name in state_names_dict: extra_info_dict['structured_name'] = state_names_dict[ param_or_buffer.name] extra_info_dict['stop_gradient'] = param_or_buffer.stop_gradient if isinstance(param_or_buffer, ParamBase): extra_info_dict['trainable'] = param_or_buffer.trainable extra_var_info[param_or_buffer.name] = extra_info_dict # 4. build input & output spec input_var_names = get_inout_spec(concrete_program.inputs, input_spec, True) output_vars = get_inout_spec(concrete_program.outputs, configs.output_spec) # 5. save inference model from paddle.fluid.io import save_inference_model # VARIABLE_FILENAME keep nameing style consistent with '__model__' if configs.params_filename is None: configs.params_filename = VARIABLE_FILENAME with scope_guard(scope): save_inference_model( dirname=model_path, feeded_var_names=input_var_names, target_vars=output_vars, executor=Executor(_current_expected_place()), main_program=concrete_program.main_program.clone(), model_filename=configs.model_filename, params_filename=None if configs.separate_params else configs.params_filename, export_for_deployment=configs._export_for_deployment, program_only=configs._program_only) # NOTE: [ Save extra variable info ] # save_inference_model will lose some important variable information, including: # - Variable name and correspondence (when saved variables as one file) # - Variable.stop_gradient information # - Which persistent variable are parameter and which are not # - Parameter.trainable information # # The lost information cannot be recovered when it is loaded again, # so if we want to perform fine-tune after loading, we may need to # configure redundant information to proceed. # # Due to compatibility issues, we cannot change the original storage structure, # but we can save these information in `jit.save` without changing the original # storage to improve user experience. So we save extra information into # file `__variables.info__` extra_var_info_path = os.path.join(model_path, EXTRA_VAR_INFO_FILENAME) with open(extra_var_info_path, 'wb') as f: pickle.dump(extra_var_info, f, protocol=2) @dygraph_only def load(model_path, configs=None): """ :api_attr: imperative Load model saved by :ref:`api_imperative_jit_save` or :ref:`api_fluid_io_save_inference_model` as :ref:`api_imperative_TranslatedLayer`, then performing inference or fine-tune training. .. note:: For some historical reasons, if you load model saved by :ref:`api_fluid_io_save_inference_model`, there will be the following limitations when using it in fine-tuning: 1. Imperative mode do not support LoDTensor. All original model's feed targets or parametars that depend on LoD are temporarily unavailable. 2. All saved model's feed targets need to be passed into TranslatedLayer's forwrad function. 3. The variable's ``stop_gradient`` information is lost and can not be recovered. 4. The parameter's ``trainable`` information is lost and can not be recovered. Args: model_path (str): The directory path where the model is saved. configs (SaveLoadConfig, optional): :ref:`api_imperative_jit_saveLoadConfig` object that specifies additional configuration options. Default None. Returns: TranslatedLayer: A Layer object can run saved translated model. Examples: 1. Load model saved by :ref:`api_imperative_jit_save` then performing inference and fine-tune training. .. code-block:: python import numpy as np import paddle.fluid as fluid from paddle.fluid.dygraph import Linear from paddle.fluid.dygraph import declarative BATCH_SIZE = 32 BATCH_NUM = 20 def random_batch_reader(): def _get_random_images_and_labels(image_shape, label_shape): image = np.random.random(size=image_shape).astype('float32') label = np.random.random(size=label_shape).astype('int64') return image, label def __reader__(): for _ in range(BATCH_NUM): batch_image, batch_label = _get_random_images_and_labels( [BATCH_SIZE, 784], [BATCH_SIZE, 1]) yield batch_image, batch_label return __reader__ class LinearNet(fluid.dygraph.Layer): def __init__(self, in_size, out_size): super(LinearNet, self).__init__() self._linear = Linear(in_size, out_size) @declarative def forward(self, x): return self._linear(x) # enable dygraph mode fluid.enable_dygraph() # 1. train & save model. # create network net = LinearNet(784, 1) adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=net.parameters()) # create data loader train_loader = fluid.io.DataLoader.from_generator(capacity=5) train_loader.set_batch_generator(random_batch_reader()) # train for data in train_loader(): img, label = data label.stop_gradient = True cost = net(img) loss = fluid.layers.cross_entropy(cost, label) avg_loss = fluid.layers.mean(loss) avg_loss.backward() adam.minimize(avg_loss) net.clear_gradients() model_path = "linear.example.model" fluid.dygraph.jit.save( layer=net, model_path=model_path, input_spec=[img]) # 2. load model & inference # load model infer_net = fluid.dygraph.jit.load(model_path) # inference x = fluid.dygraph.to_variable(np.random.random((1, 784)).astype('float32')) pred = infer_net(x) # 3. load model & fine-tune # load model train_net = fluid.dygraph.jit.load(model_path) train_net.train() adam = fluid.optimizer.AdamOptimizer(learning_rate=0.1, parameter_list=train_net.parameters()) # create data loader train_loader = fluid.io.DataLoader.from_generator(capacity=5) train_loader.set_batch_generator(random_batch_reader()) # fine-tune for data in train_loader(): img, label = data label.stop_gradient = True cost = train_net(img) loss = fluid.layers.cross_entropy(cost, label) avg_loss = fluid.layers.mean(loss) avg_loss.backward() adam.minimize(avg_loss) train_net.clear_gradients() 2. Load model saved by :ref:`api_fluid_io_save_inference_model` then performing and fine-tune training. .. code-block:: python import numpy as np import paddle.fluid as fluid BATCH_SIZE = 32 BATCH_NUM = 20 def random_batch_reader(): def _get_random_images_and_labels(image_shape, label_shape): image = np.random.random(size=image_shape).astype('float32') label = np.random.random(size=label_shape).astype('int64') return image, label def __reader__(): for _ in range(BATCH_NUM): batch_image, batch_label = _get_random_images_and_labels( [BATCH_SIZE, 784], [BATCH_SIZE, 1]) yield batch_image, batch_label return __reader__ img = fluid.data(name='img', shape=[None, 784], dtype='float32') label = fluid.data(name='label', shape=[None, 1], dtype='int64') pred = fluid.layers.fc(input=img, size=10, act='softmax') loss = fluid.layers.cross_entropy(input=pred, label=label) avg_loss = fluid.layers.mean(loss) optimizer = fluid.optimizer.SGD(learning_rate=0.001) optimizer.minimize(avg_loss) place = fluid.CPUPlace() exe = fluid.Executor(place) exe.run(fluid.default_startup_program()) loader = fluid.io.DataLoader.from_generator( feed_list=[img, label], capacity=5, iterable=True) loader.set_batch_generator(random_batch_reader(), places=place) # 1. train and save inference model for data in loader(): exe.run( fluid.default_main_program(), feed=data, fetch_list=[avg_loss]) model_path = "fc.example.model" fluid.io.save_inference_model( model_path, ["img"], [pred], exe) # enable dygraph mode fluid.enable_dygraph() # 2. load model & inference fc = fluid.dygraph.jit.load(model_path) x = fluid.dygraph.to_variable(np.random.random((1, 784)).astype('float32')) pred = fc(x) # 3. load model & fine-tune fc = fluid.dygraph.jit.load(model_path) fc.train() sgd = fluid.optimizer.SGD(learning_rate=0.001, parameter_list=fc.parameters()) train_loader = fluid.io.DataLoader.from_generator(capacity=5) train_loader.set_batch_generator( random_batch_reader(), places=place) for data in train_loader(): img, label = data label.stop_gradient = True cost = fc(img) loss = fluid.layers.cross_entropy(cost, label) avg_loss = fluid.layers.mean(loss) avg_loss.backward() sgd.minimize(avg_loss) """ return TranslatedLayer._construct(model_path, configs) @dygraph_only def _trace(layer, inputs, feed_prefix='feed_', fetch_prefix='fetch_', tmp_prefix='t_'): assert isinstance(layer, Layer) if not isinstance(inputs, (list, tuple)): inputs = [inputs] tracer = _dygraph_tracer()._get_program_desc_tracer() var_list = extract_vars(inputs) with program_desc_tracing_guard(True): original_outputs = layer(*inputs) if not isinstance(original_outputs, (list, tuple)): outputs = [original_outputs] else: outputs = original_outputs out_vars = [var for var in outputs] program_desc, feed_names, fetch_names, parameters = tracer.create_program_desc( var_list, feed_prefix, out_vars, fetch_prefix, tmp_prefix) tracer.reset() with _dygraph_guard(None): program = create_program_from_desc(program_desc) return original_outputs, program, feed_names, fetch_names, parameters class TracedLayer(object): """ :api_attr: imperative TracedLayer is used to convert a forward dygraph model to a static graph model. This is mainly used to save the dygraph model for online inference using C++. Besides, users can also do inference in Python using the converted static graph model, which usually has better performance than the original dygraph model. TracedLayer would run the static graph model using :code:`Executor` and :code:`CompiledProgram` . The static graph model would share parameters with the dygraph model. All TracedLayer objects should not be created by constructor and should be created by static method :code:`TracedLayer.trace(layer, inputs)` . The TracedLayer can only be used to convert the data-independent dygraph model into the static graph model, which means the dygraph model should be independent with the tensor data and shape. """ def __init__(self, program, parameters, feed_names, fetch_names): self._program = program self._feed_names = feed_names self._fetch_names = fetch_names self._params = parameters self._place = _current_expected_place() self._scope = core.Scope() for p in parameters: src_tensor = p.value().get_tensor() dst_tensor = self._scope.var(p.name).get_tensor() dst_tensor._share_data_with(src_tensor) self._exe = Executor(self._place) self._compiled_program = None self._build_strategy = None self._exec_strategy = None @property def program(self): return self._program def _switch(self, is_test=True): for block_id in range(self._program.num_blocks): block = self._program.block(block_id) for op in block.ops: if op.has_attr("is_test"): op._set_attr("is_test", is_test) @staticmethod @dygraph_only def trace(layer, inputs): """ This method is the only allowed method to create TracedLayer object. It would call the :code:`layer(*inputs)` method to run the dygraph model and convert it into a static graph model. Args: layer (dygraph.Layer): the layer object to be traced. inputs (list(Tensor)|tuple(Tensor)|Tensor): the input tensors of the layer object. Returns: tuple: A tuple of 2 items, whose the first item is the output of :code:`layer(*inputs)` , and the second item is the created TracedLayer object. Examples: .. code-block:: python: import paddle.fluid as fluid from paddle.fluid.dygraph import Linear, to_variable, TracedLayer import numpy as np class ExampleLayer(fluid.dygraph.Layer): def __init__(self): super(ExampleLayer, self).__init__() self._fc = Linear(3, 10) def forward(self, input): return self._fc(input) with fluid.dygraph.guard(): layer = ExampleLayer() in_np = np.random.random([2, 3]).astype('float32') in_var = to_variable(in_np) out_dygraph, static_layer = TracedLayer.trace(layer, inputs=[in_var]) # run the static graph model using Executor inside out_static_graph = static_layer([in_var]) print(len(out_static_graph)) # 1 print(out_static_graph[0].shape) # (2, 10) # save the static graph model for inference static_layer.save_inference_model(dirname='./saved_infer_model') """ assert isinstance( layer, Layer ), "The type of 'layer' in fluid.dygraph.jit.TracedLayer.trace must be fluid.dygraph.Layer, but received {}.".format( type(layer)) outs, prog, feed, fetch, parameters = _trace(layer, inputs) traced = TracedLayer(prog, parameters, feed, fetch) return outs, traced def set_strategy(self, build_strategy=None, exec_strategy=None): """ Set the strategies when running static graph model. Args: build_strategy (BuildStrategy, optional): build strategy of :code:`CompiledProgram` inside TracedLayer. Default None. exec_strategy (ExecutionStrategy, optional): execution strategy of :code:`CompiledProgram` inside TracedLayer. Default None. Returns: None Examples: .. code-block:: python: import paddle.fluid as fluid from paddle.fluid.dygraph import Linear, to_variable, TracedLayer import numpy as np class ExampleLayer(fluid.dygraph.Layer): def __init__(self): super(ExampleLayer, self).__init__() self._fc = Linear(3, 10) def forward(self, input): return self._fc(input) with fluid.dygraph.guard(): layer = ExampleLayer() in_np = np.random.random([2, 3]).astype('float32') in_var = to_variable(in_np) out_dygraph, static_layer = TracedLayer.trace(layer, inputs=[in_var]) build_strategy = fluid.BuildStrategy() build_strategy.enable_inplace = True exec_strategy = fluid.ExecutionStrategy() exec_strategy.num_threads = 2 static_layer.set_strategy(build_strategy=build_strategy, exec_strategy=exec_strategy) out_static_graph = static_layer([in_var]) """ assert self._compiled_program is None, "Cannot set strategy after run" assert isinstance( build_strategy, (type(None), BuildStrategy) ), "The type of 'build_strategy' in fluid.dygraph.jit.TracedLayer.set_strategy must be fluid.BuildStrategy, but received {}.".format( type(build_strategy)) assert isinstance( exec_strategy, (type(None), ExecutionStrategy) ), "The type of 'exec_strategy' in fluid.dygraph.jit.TracedLayer.set_strategy must be fluid.ExecutionStrategy, but received {}.".format( type(exec_strategy)) self._build_strategy = build_strategy self._exec_strategy = exec_strategy @switch_to_static_graph def _compile(self): self._compiled_program = CompiledProgram( self._program).with_data_parallel( build_strategy=self._build_strategy, exec_strategy=self._exec_strategy, places=self._place) def _build_feed(self, inputs): assert isinstance(inputs, (list, tuple)), \ "Inputs should be a list or tuple of variables" assert len(inputs) == len(self._feed_names) feed_dict = {} if in_dygraph_mode(): for x, name in zip(inputs, self._feed_names): feed_dict[name] = x.value().get_tensor() else: for x, name in zip(inputs, self._feed_names): feed_dict[name] = x return feed_dict @switch_to_static_graph def _run(self, feed): return self._exe.run(self._compiled_program, feed=feed, fetch_list=self._fetch_names) def __call__(self, inputs): with scope_guard(self._scope): if self._compiled_program is None: self._compile() return self._run(self._build_feed(inputs)) @switch_to_static_graph def save_inference_model(self, dirname, feed=None, fetch=None): """ Save the TracedLayer to a model for inference. The saved inference model can be loaded by C++ inference APIs. Args: dirname (str): the directory to save the inference model. feed (list[int], optional): the input variable indices of the saved inference model. If None, all input variables of the TracedLayer object would be the inputs of the saved inference model. Default None. fetch (list[int], optional): the output variable indices of the saved inference model. If None, all output variables of the TracedLayer object would be the outputs of the saved inference model. Default None. Returns: None Examples: .. code-block:: python: import paddle.fluid as fluid from paddle.fluid.dygraph import Linear, to_variable, TracedLayer import numpy as np class ExampleLayer(fluid.dygraph.Layer): def __init__(self): super(ExampleLayer, self).__init__() self._fc = Linear(3, 10) def forward(self, input): return self._fc(input) save_dirname = './saved_infer_model' in_np = np.random.random([2, 3]).astype('float32') with fluid.dygraph.guard(): layer = ExampleLayer() in_var = to_variable(in_np) out_dygraph, static_layer = TracedLayer.trace(layer, inputs=[in_var]) static_layer.save_inference_model(save_dirname, feed=[0], fetch=[0]) place = fluid.CPUPlace() exe = fluid.Executor(place) program, feed_vars, fetch_vars = fluid.io.load_inference_model(save_dirname, exe) fetch, = exe.run(program, feed={feed_vars[0]: in_np}, fetch_list=fetch_vars) print(fetch.shape) # (2, 10) """ check_type(dirname, "dirname", str, "fluid.dygraph.jit.TracedLayer.save_inference_model") check_type(feed, "feed", (type(None), list), "fluid.dygraph.jit.TracedLayer.save_inference_model") if isinstance(feed, list): for f in feed: check_type(f, "each element of feed", int, "fluid.dygraph.jit.TracedLayer.save_inference_model") check_type(fetch, "fetch", (type(None), list), "fluid.dygraph.jit.TracedLayer.save_inference_model") if isinstance(fetch, list): for f in fetch: check_type(f, "each element of fetch", int, "fluid.dygraph.jit.TracedLayer.save_inference_model") from paddle.fluid.io import save_inference_model def get_feed_fetch(all_vars, partial_vars): if partial_vars is None: return all_vars return [all_vars[idx] for idx in partial_vars] with scope_guard(self._scope): feeded_var_names = get_feed_fetch(self._feed_names, feed) target_var_names = get_feed_fetch(self._fetch_names, fetch) target_vars = [] for name in target_var_names: target_var = self._program.global_block().vars.get(name, None) assert target_var is not None, "{} cannot be found".format(name) target_vars.append(target_var) save_inference_model( dirname=dirname, feeded_var_names=feeded_var_names, target_vars=target_vars, executor=self._exe, main_program=self._program.clone())