fleet_base.py 35.0 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
#   Copyright (c) 2020 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
16
import copy
17
import warnings
18
import paddle
19
from paddle.fluid.framework import dygraph_only
20
from paddle.fluid import compiler
21
from .role_maker import UserDefinedRoleMaker, PaddleCloudRoleMaker, RoleMakerBase
22
from .strategy_compiler import StrategyCompiler
23
from .distributed_strategy import DistributedStrategy
24 25 26
from .meta_optimizer_factory import MetaOptimizerFactory
from .runtime_factory import RuntimeFactory
from .util_factory import UtilFactory
27
from paddle.fluid.wrapped_decorator import wrap_decorator
28
from paddle.fluid.dygraph import parallel_helper
29

30

31 32 33 34 35 36 37 38 39 40 41 42
def _inited_runtime_handler_(func):
    def __impl__(*args, **kwargs):
        cls = args[0]

        if cls._runtime_handle is None:
            raise ValueError("Fleet can not find suitable runtime handler")

        return func(*args, **kwargs)

    return __impl__


43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
def _is_non_distributed_check_(func):
    def __impl__(*args, **kwargs):
        cls = args[0]

        if cls._role_maker is not None and cls._role_maker._is_non_distributed(
        ) is True:
            warnings.warn(
                "%s() function doesn't work when use non_distributed fleet." %
                (func.__name__))
            return

        return func(*args, **kwargs)

    return __impl__


59
inited_runtime_handler = wrap_decorator(_inited_runtime_handler_)
60
is_non_distributed_check = wrap_decorator(_is_non_distributed_check_)
61 62


63 64 65
class Fleet(object):
    """
    Unified API for distributed training of PaddlePaddle
66
    Please reference the https://github.com/PaddlePaddle/FleetX for details
67 68 69 70 71


    Returns:
        Fleet: A Fleet instance

72
    Example for collective training:
73 74
        .. code-block:: python

75
            import paddle.distributed.fleet as fleet
76 77 78

            fleet.init(is_collective=True)

79 80 81
            strategy = fleet.DistributedStrategy()
            optimizer = paddle.optimizer.SGD(learning_rate=0.001)
            optimizer = fleet.distributed_optimizer(optimizer, strategy=strategy)
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97

            # do distributed training


    Example for parameter server training:

        .. code-block:: python

            import paddle.distributed.fleet as fleet

            fleet.init()

            strategy = fleet.DistributedStrategy()
            optimizer = paddle.optimizer.SGD(learning_rate=0.001)
            optimizer = fleet.distributed_optimizer(optimizer, strategy=strategy)

98 99
            if fleet.is_first_worker():
                print("this is first worker")
100

101 102
            print("current node index: {}".format(fleet.worker_index()))
            print("total number of worker num: {}".format(fleet.worker_num()))
103

104 105 106
            if fleet.is_worker():
                print("this is worker")
            print("worker endpoints: {}".format(fleet.worker_endpoints(to_string=True)))
107

108 109
            print("server num: {}".format(fleet.server_num()))
            print("server endpoints: {}".format(fleet.server_endpoints(to_string=True)))
110

111 112 113
            if fleet.is_server():
                print("this is server")
            fleet.stop_worker()
114 115


116 117 118
    """

    def __init__(self):
119
        self._role_maker = None
120
        self.strategy_compiler = None
121
        self._is_collective = False
122 123
        self._runtime_handle = None
        self._util = None
124

125 126 127 128
    def init(self, role_maker=None, is_collective=False):
        """
        Initialize role_maker in Fleet.

129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163
        This function is responsible for the distributed architecture
        what you want to run your code behind.

        Args:
            role_maker (RoleMakerBase, optional): A ``RoleMakerBase`` containing the configuration
                of environment variables related to distributed training.If you did not initialize 
                the rolemaker by yourself, it will be automatically initialized to PaddleRoleMaker.
                The default value is None.
            is_collective (Boolean, optional): A ``Boolean`` variable determines whether the program 
                runs on the CPU or GPU. False means set distributed training using CPU, and True means
                GPU.The default value is False.The default value is False.
        Returns:
            None

        Examples1:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

        Examples2:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init(is_collective=True)

        Examples3:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                role = fleet.PaddleCloudRoleMaker
                fleet.init(role)
164

165
        """
166 167

        if role_maker is None:
168 169 170 171 172 173
            if isinstance(is_collective, bool):
                self._is_collective = is_collective
                self._role_maker = PaddleCloudRoleMaker(
                    is_collective=self._is_collective)
            else:
                raise ValueError(
174 175
                    "`is_collective` should be instance of `bool`, but got {}".
                    format(type(is_collective)))
176
        else:
177 178 179 180 181 182
            if isinstance(role_maker, RoleMakerBase):
                self._role_maker = role_maker
            else:
                raise ValueError(
                    "`role_maker` should be subclass of `RoleMakerBase`, but got {}".
                    format(type(role_maker)))
183
        self.strategy_compiler = StrategyCompiler()
184 185 186 187 188 189
        if paddle.fluid.framework.in_dygraph_mode():
            if parallel_helper._is_parallel_ctx_initialized():
                warnings.warn(
                    "The dygraph parallel environment has been initialized.")
            else:
                paddle.distributed.init_parallel_env()
190
        return None
191

J
jingqinghe 已提交
192 193 194
    def _role_maker_(self):
        return self._role_maker

195 196 197 198 199 200 201
    def is_first_worker(self):
        """
        Check whether the node is the first instance of worker.

        Returns:
            bool: True if this is the first node of worker,
                  False if not.
202

203 204 205 206 207 208 209 210
        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.is_first_worker()

211 212 213 214 215 216 217 218 219
        """
        return self._role_maker.is_first_worker()

    def worker_index(self):
        """
        Get current worker index.

        Returns:
            int: node id
220 221 222 223 224 225 226 227

        Examples:

            .. code-block:: python
                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.worker_index()

228 229 230 231 232 233 234 235 236
        """
        return self._role_maker.worker_index()

    def worker_num(self):
        """
        Get current total worker number.

        Returns:
            int: worker numbers
237

238 239 240 241 242 243 244
        Examples:
            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.worker_num()

245 246 247 248 249 250 251 252 253 254
        """
        return self._role_maker.worker_num()

    def is_worker(self):
        """
        Check whether the node is an instance of worker.

        Returns:
            bool: True if this is a node of worker,
                  False if not.
255 256 257 258 259 260 261 262

        Examples:
            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.is_worker()

263 264 265 266 267
        """
        return self._role_maker.is_worker()

    def worker_endpoints(self, to_string=False):
        """
268
        Get current worker endpoints, such as ["127.0.0.1:1001", "127.0.0.1:1002"].
269 270 271

        Returns:
            list/string: server endpoints
272 273 274 275 276 277 278 279

        Examples:
            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.worker_endpoints()

280 281 282 283 284 285 286 287 288 289 290 291 292 293 294
        """
        '''
        if to_string:
            return ",".join(self._role_maker.get_trainer_endpoints())
        else:
            return self._role_maker.get_trainer_endpoints()
        '''
        return ["127.0.0.1:1001", "127.0.0.1:1002"]

    def server_num(self):
        """
        Get current total worker number.

        Returns:
            int: server number
295 296 297 298 299 300

        Examples:
            .. code-block:: python
            import paddle.distributed.fleet as fleet
            fleet.init()
            fleet.server_num()
301 302 303 304 305 306 307 308 309
        """
        return len(self._role_maker.get_pserver_endpoints())

    def server_index(self):
        """
        Get current server index.

        Returns:
            int: node id
310 311 312 313 314 315 316 317

        Examples:
            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.server_index()

318 319 320 321 322 323 324 325 326
        """
        return self._role_maker.server_index()

    def server_endpoints(self, to_string=False):
        """
        Get current server endpoints, such as ["127.0.0.1:1001", "127.0.0.1:1002"].

        Returns:
            list/string: server endpoints
327 328 329 330 331 332 333 334

        Examples:
            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.server_endpoints()

335
        """
336

337 338 339 340 341 342 343 344 345 346 347 348
        if to_string:
            return ",".join(self._role_maker.get_pserver_endpoints())
        else:
            return self._role_maker.get_pserver_endpoints()

    def is_server(self):
        """
        Check whether the node is an instance of server.

        Returns:
            bool: True if this is a node of server,
                  False if not.
349 350 351 352 353 354 355 356

        Examples:

            .. code-block:: python
                import paddle.distributed.fleet as fleet
                fleet.init()
                fleet.is_server()

357
        """
358 359
        return self._role_maker.is_server(
        ) or self._role_maker._is_heter_worker()
360 361 362 363 364 365

    @property
    def util(self):
        """
        Utility functions that can be used under certain runtime
        return util
366 367 368 369 370 371 372 373 374 375 376 377 378

        Returns:
            UtilBase: instance of UtilBase, can use distributed ops/tools easily.

        Examples:

            .. code-block:: python
                import paddle.distributed.fleet as fleet
                fleet.init()
                util = fleet.util
                files = ["1.log", "2.log", "3.log", "4.log"]
                files = util.get_file_shard()

379 380 381 382 383 384 385
        """
        return self._util

    @util.setter
    def util(self, util):
        """
        Set Utility functions for userd-defined runtime
386 387 388

        Returns:
            None
389 390 391 392 393
        """
        self._util = util

    def barrier_worker(self):
        """
394 395 396 397
        barrier all workers

        Returns:
            None
398 399 400
        """
        self._role_maker.barrier_worker()

401
    @is_non_distributed_check
402
    @inited_runtime_handler
403 404
    def init_worker(self):
        """
405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422
        initialize `Communicator` for parameter server training.


        Returns:
            None

        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                fleet.init_worker()

423 424 425
        """
        self._runtime_handle._init_worker()

426
    @is_non_distributed_check
427
    @inited_runtime_handler
428
    def init_server(self, *args, **kwargs):
429
        """
430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448
        init_server executor to initialize startup program,
        if the `args` is not empty, it will run load_persistables for increment training.


        Returns:
            None

        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                fleet.init_server()

449
        """
450
        self._runtime_handle._init_server(*args, **kwargs)
451

452
    @is_non_distributed_check
453
    @inited_runtime_handler
454 455
    def run_server(self):
        """
456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473
        run server will run pserver main program with executor.

        Returns:
            None

        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                if fleet.is_server():
                    fleet.init_server()

474 475 476
        """
        self._runtime_handle._run_server()

477
    @is_non_distributed_check
478
    @inited_runtime_handler
479 480
    def stop_worker(self):
        """
481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497
        stop `Communicator` and give training complete notice to parameter server.

        Returns:
            None

        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                fleet.init_server()

498 499 500
        """
        self._runtime_handle._stop_worker()

501 502 503 504 505 506 507
    def save_inference_model(self,
                             executor,
                             dirname,
                             feeded_var_names,
                             target_vars,
                             main_program=None,
                             export_for_deployment=True):
508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527
        """
        save inference model for inference.

        Returns:
            None

        Examples:

            .. code-block:: python

                import paddle.distributed.fleet as fleet
                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                fleet.init_server()

        """

528 529 530 531 532
        self._runtime_handle._save_inference_model(
            executor, dirname, feeded_var_names, target_vars, main_program,
            export_for_deployment)

    def save_persistables(self, executor, dirname, main_program=None):
533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572
        """

        saves all persistable variables from :code:`main_program` to
        the folder :code:`dirname`. You can refer to

        The :code:`dirname` is used to specify the folder where persistable variables
        are going to be saved. If you would like to save variables in separate
        files, set :code:`filename` None.

        Args:
            executor(Executor): The executor to run for saving persistable variables.
                                You can refer to :ref:`api_guide_executor_en` for
                                more details.

            dirname(str, optional): The saving directory path.
                                When you need to save the parameter to the memory, set it to None.
            main_program(Program, optional): The program whose persistbale variables will
                                             be saved. Default: None.


        Returns:
            None

        Examples:

            .. code-block:: text

                import paddle.distributed.fleet as fleet
                import paddle.fluid as fluid

                fleet.init()

                # build net
                # fleet.distributed_optimizer(...)

                exe = fluid.Executor(fluid.CPUPlace())
                fleet.save_persistables(exe, "dirname", fluid.default_main_program())

        """

573 574
        self._runtime_handle._save_persistables(executor, dirname, main_program)

575
    def distributed_optimizer(self, optimizer, strategy=None):
576
        """
577 578 579 580 581 582 583 584 585
        Optimizer for distributed training.

        For the distributed training, this method would rebuild a new instance of DistributedOptimizer.
        Which has basic Optimizer function and special features for distributed training.

        Args:
            optimizer(Optimizer): The executor to run for init server.
            strategy(DistributedStrategy): Extra properties for distributed optimizer.

586
        Returns:
587
            Fleet: instance of fleet.
588 589

        Examples:
590

591
            .. code-block:: python
592 593 594 595 596 597 598 599

                import paddle.distributed.fleet as fleet
                role = fleet.role_maker.PaddleCloudRoleMaker(is_collective=True)
                fleet.init(role)
                strategy = fleet.DistributedStrategy()
                optimizer = paddle.optimizer.SGD(learning_rate=0.001)
                optimizer = fleet.distributed_optimizer(optimizer, strategy=strategy)

600 601
        """
        self.user_defined_optimizer = optimizer
602 603 604
        if paddle.fluid.framework.in_dygraph_mode():
            return self

605 606
        if strategy == None:
            strategy = DistributedStrategy()
607
        self.user_defined_strategy = strategy
D
Dong Daxiang 已提交
608
        self.valid_strategy = None
609 610
        return self

611 612 613
    @dygraph_only
    def distributed_model(self, model):
        """
614 615 616 617 618 619 620
        Return distributed data parallel model (Only work in dygraph mode)

        Args:
            model (Layer): the user-defind model which inherits Layer.

        Returns:
            distributed data parallel model which inherits Layer.
621 622

        Examples:
623

624 625
            .. code-block:: python

626 627 628 629 630 631 632 633 634
                import paddle
                import paddle.nn as nn
                from paddle.distributed import fleet

                class LinearNet(nn.Layer):
                    def __init__(self):
                        super(LinearNet, self).__init__()
                        self._linear1 = nn.Linear(10, 10)
                        self._linear2 = nn.Linear(10, 1)
635

636 637
                    def forward(self, x):
                        return self._linear2(self._linear1(x))
638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669

                # 1. enable dynamic mode
                paddle.disable_static()

                # 2. initialize fleet environment
                fleet.init(is_collective=True)

                # 3. create layer & optimizer
                layer = LinearNet()
                loss_fn = nn.MSELoss()
                adam = paddle.optimizer.Adam(
                    learning_rate=0.001, parameters=layer.parameters())

                # 4. get data_parallel model using fleet
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)

                # 5. run layer
                inputs = paddle.randn([10, 10], 'float32')
                outputs = dp_layer(inputs)
                labels = paddle.randn([10, 1], 'float32')
                loss = loss_fn(outputs, labels)

                print("loss:", loss.numpy())

                loss = dp_layer.scale_loss(loss)
                loss.backward()
                dp_layer.apply_collective_grads()

                adam.step()
                adam.clear_grad()

670

671 672 673 674 675 676 677 678 679
        """
        assert model is not None
        self.model = paddle.DataParallel(model)
        return self.model

    @dygraph_only
    def state_dict(self):
        """
        Get state dict information from optimizer.
680
        (Only work in dygraph mode)
681 682 683 684 685 686 687

        Returns: 
            state_dict(dict) : dict contains all the Tensor used by optimizer

        Examples:
            .. code-block:: python

688 689 690 691 692 693
                import numpy as np
                import paddle
                from paddle.distributed import fleet

                paddle.disable_static()
                fleet.init(is_collective=True)
694

695 696
                value = np.arange(26).reshape(2, 13).astype("float32")
                a = paddle.fluid.dygraph.to_variable(value)
697

698 699
                layer = paddle.nn.Linear(13, 5)
                adam = paddle.optimizer.Adam(learning_rate=0.01, parameters=layer.parameters())
700

701 702 703
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)
                state_dict = adam.state_dict()
704 705 706 707 708 709 710 711
        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.state_dict()

    @dygraph_only
    def set_state_dict(self, state_dict):
        """
        Load optimizer state dict.
712
        (Only work in dygraph mode)
713 714 715 716

        Args: 
            state_dict(dict) : Dict contains all the Tensor needed by optimizer

717 718
        Returns:
            None
719 720 721 722

        Examples:
            .. code-block:: python

723 724 725
                import numpy as np
                import paddle
                from paddle.distributed import fleet
726

727 728 729 730 731
                paddle.disable_static()
                fleet.init(is_collective=True)

                value = np.arange(26).reshape(2, 13).astype("float32")
                a = paddle.fluid.dygraph.to_variable(value)
732

733 734
                layer = paddle.nn.Linear(13, 5)
                adam = paddle.optimizer.Adam(learning_rate=0.01, parameters=layer.parameters())
735

736 737 738 739 740 741
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)
                state_dict = adam.state_dict()
                paddle.framework.save(state_dict, "paddle_dy")
                para_state_dict, opti_state_dict = paddle.framework.load( "paddle_dy")
                adam.set_state_dict(opti_state_dict)
742 743 744 745 746 747 748 749
        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.set_state_dict(state_dict)

    @dygraph_only
    def set_lr(self, value):
        """
        Set the value of the learning rate manually in the optimizer. 
750
        (Only work in dygraph mode)
751

752 753 754
        Args:
            value (float|Tensor): the value of learning rate

755 756
        Returns: 
            None 
757 758 759 760

        Examples:
            .. code-block:: python

761 762 763
                import numpy as np
                import paddle
                from paddle.distributed import fleet
764

765 766
                paddle.disable_static()
                fleet.init(is_collective=True)
767

768 769
                value = np.arange(26).reshape(2, 13).astype("float32")
                a = paddle.fluid.dygraph.to_variable(value)
770

771 772
                layer = paddle.nn.Linear(13, 5)
                adam = paddle.optimizer.Adam(learning_rate=0.01, parameters=layer.parameters())
773

774 775 776 777 778 779 780 781 782 783 784 785 786 787
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)

                lr_list = [0.2, 0.3, 0.4, 0.5, 0.6]
                for i in range(5):
                    adam.set_lr(lr_list[i])
                    lr = adam.get_lr()
                    print("current lr is {}".format(lr))
                # Print:
                #    current lr is 0.2
                #    current lr is 0.3
                #    current lr is 0.4
                #    current lr is 0.5
                #    current lr is 0.6
788 789 790 791 792 793 794 795
        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.set_lr(value)

    @dygraph_only
    def get_lr(self):
        """
        Get current step learning rate.
796
        (Only work in dygraph mode)
797 798 799 800 801 802 803

        Returns:
            float: The learning rate of the current step.

        Examples:
            .. code-block:: python

804 805 806 807 808 809
                import numpy as np
                import paddle
                from paddle.distributed import fleet

                paddle.disable_static()
                fleet.init(is_collective=True)
810

811 812
                value = np.arange(26).reshape(2, 13).astype("float32")
                a = paddle.fluid.dygraph.to_variable(value)
813

814 815
                layer = paddle.nn.Linear(13, 5)
                adam = paddle.optimizer.Adam(learning_rate=0.01, parameters=layer.parameters())
816

817 818
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)
819

820 821
                lr = adam.get_lr()
                print(lr) # 0.01
822 823 824 825 826 827 828 829
        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.get_lr()

    @dygraph_only
    def step(self):
        """
        Execute the optimizer once.
830
        (Only work in dygraph mode)
831

832 833
        Returns:
            None
834 835 836 837

        Examples:
            .. code-block:: python

838 839 840
                import paddle
                import paddle.nn as nn
                from paddle.distributed import fleet
841

842 843 844 845 846
                class LinearNet(nn.Layer):
                    def __init__(self):
                        super(LinearNet, self).__init__()
                        self._linear1 = nn.Linear(10, 10)
                        self._linear2 = nn.Linear(10, 1)
847

848 849
                    def forward(self, x):
                        return self._linear2(self._linear1(x))
850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889

                # 1. enable dynamic mode
                paddle.disable_static()

                # 2. initialize fleet environment
                fleet.init(is_collective=True)

                # 3. create layer & optimizer
                layer = LinearNet()
                loss_fn = nn.MSELoss()
                adam = paddle.optimizer.Adam(
                    learning_rate=0.001, parameters=layer.parameters())

                # 4. get data_parallel model using fleet
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)

                # 5. run layer
                inputs = paddle.randn([10, 10], 'float32')
                outputs = dp_layer(inputs)
                labels = paddle.randn([10, 1], 'float32')
                loss = loss_fn(outputs, labels)

                print("loss:", loss.numpy())

                loss = dp_layer.scale_loss(loss)
                loss.backward()
                dp_layer.apply_collective_grads()

                adam.step()
                adam.clear_grad()


        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.step()

    @dygraph_only
    def clear_grad(self):
        """
890 891
        Clear the gradients of all optimized parameters for model.
        (Only work in dygraph mode)
892

893 894
        Returns: 
            None
895 896 897 898

        Examples:
            .. code-block:: python

899 900 901
                import paddle
                import paddle.nn as nn
                from paddle.distributed import fleet
902

903 904 905 906 907
                class LinearNet(nn.Layer):
                    def __init__(self):
                        super(LinearNet, self).__init__()
                        self._linear1 = nn.Linear(10, 10)
                        self._linear2 = nn.Linear(10, 1)
908

909 910
                    def forward(self, x):
                        return self._linear2(self._linear1(x))
911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946

                # 1. enable dynamic mode
                paddle.disable_static()

                # 2. initialize fleet environment
                fleet.init(is_collective=True)

                # 3. create layer & optimizer
                layer = LinearNet()
                loss_fn = nn.MSELoss()
                adam = paddle.optimizer.Adam(
                    learning_rate=0.001, parameters=layer.parameters())

                # 4. get data_parallel model using fleet
                adam = fleet.distributed_optimizer(adam)
                dp_layer = fleet.distributed_model(layer)

                # 5. run layer
                inputs = paddle.randn([10, 10], 'float32')
                outputs = dp_layer(inputs)
                labels = paddle.randn([10, 1], 'float32')
                loss = loss_fn(outputs, labels)

                print("loss:", loss.numpy())

                loss = dp_layer.scale_loss(loss)
                loss.backward()
                dp_layer.apply_collective_grads()

                adam.step()
                adam.clear_grad()

        """
        # imitate target optimizer retrieval
        return self.user_defined_optimizer.clear_grad()

947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
    def minimize(self,
                 loss,
                 startup_program=None,
                 parameter_list=None,
                 no_grad_set=None):
        """
        Add distributed operations to minimize ``loss`` by updating ``parameter_list``.

        Args:
            loss (Variable): A ``Variable`` containing the value to minimize.
            startup_program (Program, optional): :ref:`api_fluid_Program` for
                initializing parameters in ``parameter_list``. The default value
                is None, at this time :ref:`api_fluid_default_startup_program` will be used.
            parameter_list (Iterable, optional): Iterable of ``Variable`` or ``Variable.name`` to update
                to minimize ``loss``. The default value is None, at this time all parameters
                will be updated.
            no_grad_set (set, optional): Set of ``Variable``  or ``Variable.name`` that don't need
                to be updated. The default value is None.

        Returns:
            tuple: tuple (optimize_ops, params_grads), A list of operators appended
            by minimize and a list of (param, grad) variable pairs, param is
            ``Parameter``, grad is the gradient value corresponding to the parameter.
970 971
            The returned tuple can be passed to ``fetch_list`` in ``Executor.run()`` to
            indicate program pruning. If so, the program will be pruned by ``feed`` and
972 973 974
            ``fetch_list`` before run, see details in ``Executor``.

        Examples:
975
            .. code-block:: python
976

977 978
                import paddle
                import paddle.distributed.fleet as fleet
979

980 981 982 983 984 985 986 987 988 989 990 991
                fc_1 = paddle.fluid.layers.fc(input=input_x, size=hid_dim, act='tanh')
                fc_2 = paddle.fluid.layers.fc(input=fc_1, size=hid_dim, act='tanh')
                prediction = paddle.fluid.layers.fc(input=[fc_2], size=label_dim, act='softmax')
                cost = paddle.fluid.layers.cross_entropy(input=prediction, label=input_y)
                avg_cost = paddle.fluid.layers.mean(x=cost)

                role = fleet.role_maker.PaddleCloudRoleMaker(is_collective=True)
                fleet.init(role)
                strategy = fleet.DistributedStrategy()
                optimizer = paddle.optimizer.SGD(learning_rate=0.001)
                optimizer = fleet.distributed_optimizer(optimizer, strategy=strategy)
                optimizer.minimize(avg_cost)
992

993
                # for more examples, please reference https://github.com/PaddlePaddle/FleetX
994 995

        """
996 997 998 999 1000
        if paddle.fluid.framework.in_dygraph_mode():
            # imitate target optimizer retrieval
            target_opt = self.user_defined_optimizer
            return target_opt.minimize(loss)

1001
        context = {}
1002 1003
        # cache original feed forward program
        self.origin_main_program = loss.block.program
1004 1005
        context["origin_main_program"] = self.origin_main_program
        context["loss"] = loss
1006 1007
        if startup_program == None:
            self.origin_startup_program = \
1008 1009
                paddle.static.default_startup_program().clone(for_test=False)
            startup_program = paddle.static.default_startup_program()
1010 1011 1012
        else:
            self.origin_startup_program = \
                startup_program.clone(for_test=False)
1013

1014 1015
        context["origin_startup_program"] = startup_program
        context["role_maker"] = self._role_maker
1016 1017 1018 1019 1020

        # compile time
        distributed_optimizer_list = \
            MetaOptimizerFactory()._get_valid_meta_optimizers(
                self.user_defined_optimizer)
D
Dong Daxiang 已提交
1021

1022 1023 1024 1025 1026 1027 1028 1029 1030 1031
        context["user_defined_strategy"] = copy.copy(self.user_defined_strategy)

        # trigger the auto-parallel in very strict condition
        # strategy = DistributedStrategy()
        # strategy.auto = True
        # optimizer = paddle.optimizer.SGD(learning_rate=0.1)
        # optimizer = fleet.distributed_optimizer(optimizer, strategy)
        if self.user_defined_strategy._is_strict_auto():
            # turn on all the strategy for each optimizer
            for opt in distributed_optimizer_list:
1032
                opt._enable_strategy(self.user_defined_strategy, context)
1033

1034 1035
        valid_optimizer_list = []
        valid_graph_optimizer_list = []
D
Dong Daxiang 已提交
1036
        can_not_apply_optimizer_list = []
1037 1038 1039 1040 1041 1042 1043
        # recall meta optimizers for ranking
        for opt in distributed_optimizer_list:
            opt._set_basic_info(loss, self._role_maker,
                                self.user_defined_optimizer,
                                self.user_defined_strategy)
            if opt._can_apply() and not opt._is_graph_out():
                valid_optimizer_list.append(opt)
D
Dong Daxiang 已提交
1044
            elif opt._can_apply() and opt._is_graph_out():
1045
                valid_graph_optimizer_list.append(opt)
D
Dong Daxiang 已提交
1046 1047
            else:
                can_not_apply_optimizer_list.append(opt)
1048
        # combine recalled meta optimizers to be a valid meta optimizer
D
Dong Daxiang 已提交
1049
        meta_optimizer, graph_optimizer = \
1050 1051 1052 1053
            self.strategy_compiler.generate_optimizer(
                loss, self._role_maker, self.user_defined_optimizer,
                self.user_defined_strategy, valid_optimizer_list,
                valid_graph_optimizer_list)
D
Dong Daxiang 已提交
1054

D
Dong Daxiang 已提交
1055 1056
        valid_strategy = self.strategy_compiler._get_valid_strategy(
            self.user_defined_strategy, can_not_apply_optimizer_list)
1057 1058 1059

        context["valid_strategy"] = valid_strategy

D
Dong Daxiang 已提交
1060
        self.valid_strategy = valid_strategy
1061
        self.valid_strategy._enable_env()
D
Dong Daxiang 已提交
1062

1063 1064
        optimize_ops = []
        params_grads = []
1065

1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079
        if self._role_maker._is_non_distributed() and not self._is_collective:
            if self._runtime_handle is None:
                self._runtime_handle = RuntimeFactory()._create_runtime(context)

            compiled_program = compiler.CompiledProgram(
                self.origin_main_program).with_data_parallel(
                    loss_name=loss.name, share_vars_from=None)
            loss.block.program._graph = compiled_program
            return self.user_defined_optimizer.minimize(
                loss,
                startup_program=startup_program,
                parameter_list=parameter_list,
                no_grad_set=no_grad_set)

1080 1081 1082 1083 1084 1085
        if meta_optimizer:
            optimize_ops, params_grads = meta_optimizer.minimize(
                loss,
                startup_program=startup_program,
                parameter_list=parameter_list,
                no_grad_set=no_grad_set)
1086

1087
            default_program = paddle.static.default_main_program()
1088 1089 1090 1091

            if id(default_program) != id(loss.block.program):
                paddle.fluid.framework.switch_main_program(loss.block.program)

1092 1093 1094 1095 1096 1097
        else:
            optimize_ops, params_grads = self.user_defined_optimizer.minimize(
                loss,
                startup_program=startup_program,
                parameter_list=parameter_list,
                no_grad_set=no_grad_set)
1098

1099 1100
        context["program_optimize_ops"] = optimize_ops
        context["program_params_grads"] = params_grads
1101

1102
        if graph_optimizer:
D
Dong Daxiang 已提交
1103
            optimize_ops, params_grads = graph_optimizer.minimize(
1104 1105 1106 1107 1108 1109 1110 1111
                loss,
                startup_program=startup_program,
                parameter_list=parameter_list,
                no_grad_set=no_grad_set)
            # since we do not encourage users to use graph operations
            # if a graph optimizer takes effect, mostly
            # optimizers_ops and params_grads are None
            # i.e. users can not modify current computation graph anymore
1112 1113 1114
            context["graph_optimize_ops"] = optimize_ops
            context["graph_optimize_grads"] = params_grads

1115
        if self._runtime_handle is None:
1116
            self._runtime_handle = RuntimeFactory()._create_runtime(context)
1117 1118

        if self._util is None:
1119
            self._util = UtilFactory()._create_util(context)
1120 1121

        return optimize_ops, params_grads