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PArallel Distributed Deep LEarning: Machine Learning Framework from Industrial Practice (『飞桨』核心框架,深度学习&机器学习高性能单机、分布式训练和跨平台部署)

# 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 jin 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 annotations
import itertools
import os
import sys
import time
import warnings
from collections import OrderedDict, namedtuple
from contextlib import contextmanager
from multiprocessing import Manager, Process
from typing import (
TYPE_CHECKING,
Any,
)
import numpy as np
import paddle
from paddle import _legacy_C_ops, framework
from paddle.base.core import get_all_custom_device_type
from paddle.distributed.collective import (
Group,
_default_group_name,
_get_group_map_by_name,
_new_process_group_impl,
_set_default_backend,
_set_default_store,
_set_group_map,
_set_group_map_backend,
_set_group_map_by_name,
_valid_backend_list,
)
from paddle.distributed.communication.group import (
_add_new_group,
_get_global_group,
is_initialized,
)
from paddle.distributed.fleet.base.private_helper_function import (
wait_server_ready,
)
from paddle.distributed.fleet.launch_utils import check_backend
# (TODO: GhostScreaming) It will be removed later.
from paddle.framework import (
_set_expected_place,
base as imperative_base,
core,
in_dynamic_mode,
)
from paddle.nn.layer import Layer
from paddle.utils import deprecated
from . import parallel_helper
from .backup_env import getenv_or_backup
if TYPE_CHECKING:
from collections.abc import Generator
from paddle import Tensor
from paddle.base.libpaddle import NCCLConfig
from paddle.nn.layer.layers import _StateDict
__all__ = []
ParallelStrategy = core.ParallelStrategy
def _build_default_parallel_strategy():
strategy = ParallelStrategy()
strategy.nranks = paddle.distributed.ParallelEnv().nranks
strategy.local_rank = paddle.distributed.ParallelEnv().local_rank
strategy.trainer_endpoints = (
paddle.distributed.ParallelEnv().trainer_endpoints
)
strategy.current_endpoint = (
paddle.distributed.ParallelEnv().current_endpoint
)
return strategy
def _coalesce_tensors(var_groups):
coalesced_grads_and_grad_vars = []
for group_id, grad_vars in var_groups.items():
flattened_vars = []
g_var_shapes = []
for g_var in grad_vars:
g_var_shapes.append(g_var.shape)
flattened_vars.append(
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paddle.reshape(
x=g_var, shape=[np.prod(g_var.shape, dtype="int64")]
)
)
coalesced_grad = paddle.concat(flattened_vars)
coalesced_grads_and_grad_vars.append(
[coalesced_grad, grad_vars, g_var_shapes]
)
return coalesced_grads_and_grad_vars
@framework.dygraph_only
def _reshape_inplace(x, shape):
x_shape = framework._create_tensor(dtype=x.dtype)
framework._dygraph_tracer().trace_op(
type="reshape2",
inputs={'X': x},
outputs={'Out': x, 'XShape': x_shape},
attrs={'shape': shape},
)
@framework.dygraph_only
def _split_tensors(coalesced_grads_and_grad_vars):
if in_dynamic_mode():
for (
coalesced_grad,
origin_grad_vars,
grad_shapes,
) in coalesced_grads_and_grad_vars:
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grad_var_len = [
np.prod(g_shape, dtype="int64") for g_shape in grad_shapes
]
attrs = ()
attrs += ('sections', grad_var_len)
attrs += ('axis', 0)
_legacy_C_ops.split(coalesced_grad, origin_grad_vars, *attrs)
for g_var, g_shape in zip(origin_grad_vars, grad_shapes):
g_var.reshape_(shape=g_shape)
assert g_var.shape == g_shape
@imperative_base.no_grad
@framework.dygraph_only
def build_groups(
vars: list[Tensor], group_size: int
) -> list[list[Tensor | list[Tensor] | list[int]]]:
group_idx = 0
memory_counter = 0
var_groups = OrderedDict()
dtype = vars[0].dtype
for var in vars:
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var_dtype = var.dtype
if isinstance(var_dtype, core.DataType):
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var_dtype = paddle.pir.core.datatype_to_vartype[var_dtype]
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bytes = np.prod(var.shape, dtype="int64") * core.size_of_dtype(
var_dtype
)
if memory_counter < group_size and dtype == var.dtype:
memory_counter += bytes
else:
memory_counter = bytes
dtype = var.dtype
group_idx += 1
var_groups.setdefault(group_idx, []).append(var)
return _coalesce_tensors(var_groups)
@imperative_base.no_grad
@framework.dygraph_only
def sync_params_buffers(
model: Layer,
comm_group: Group | None = None,
src_rank: int = 0,
is_model_parallel: bool = False,
fuse_params: bool = True,
is_moe_sharding_parallel: bool = False,
) -> None:
model_vars = []
for _, param in model._obtain_parameters_buffers().items():
if not isinstance(param, core.eager.Tensor):
raise TypeError(
f"The data type of '{param.name}' must be core.eager.Tensor"
)
if is_model_parallel:
if hasattr(param, "is_distributed") and param.is_distributed:
continue
if not is_moe_sharding_parallel:
# NOTE(shenliang03): Support situations that do not require synchronization parameters,
# such as moe's expert parameters
if getattr(param, "no_sync", False):
continue
else:
# NOTE(zhangyuqin1998): In moe sharding parallel, we do need to broadcast expert parameters
# in moe sharding group.
if getattr(param, "no_sync", False) and not getattr(
param, "expert", False
):
continue
if param.type == core.VarDesc.VarType.VOCAB:
continue
model_vars.append(param.detach())
if len(model_vars) == 0:
return
if fuse_params:
# group size is 128M
coalesced_vars = build_groups(model_vars, 128 * 1024 * 1024)
for coalesced_var, _, _ in coalesced_vars:
paddle.distributed.broadcast(
coalesced_var, src=src_rank, group=comm_group, sync_op=True
)
for coalesced_var, origin_vars, var_shapes in coalesced_vars:
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var_len = [
np.prod(v_shape, dtype="int64") for v_shape in var_shapes
]
paddle.base.framework._dygraph_tracer().trace_op(
type='split',
inputs={'X': coalesced_var},
outputs={'Out': origin_vars},
attrs={'sections': var_len, 'axis': 0},
)
else:
for var in model_vars:
# NOTE(shenliang03): Now, we dont support contiguous tensor in dp
var = var.contiguous()
paddle.distributed.broadcast(
var, src=src_rank, group=comm_group, sync_op=True
)
class DataParallel(Layer):
"""
Run the dygraph module with data parallelism.
Currently, DataParallel class only supports to run the dynamic graph
with multi-process.
Now supports two ways to start training:
1. start by ``paddle.distributed.spawn`` method, for example:
``python demo.py`` (spawn need to be called in ``__main__`` method)
2. start by ``paddle.distributed.launch`` module, for example:
``python -m paddle.distributed.launch --gpus=0,1 demo.py`` .
And the content of `demo.py` is the code of examples.
Args:
layers(Layer): The module that should be executed by data parallel.
strategy(ParallelStrategy, optional): (deprecated) The strategy of data parallelism,
contains environment configuration related to parallel execution. Default: None.
comm_buffer_size(int, optional): It limits the memory size(MB) of one buffer
parameters' gradient which is the input of communication
calling(e.g NCCLAllReduce). Default: 25.
last_comm_buffer_size(float, optional): It limits memory size(MB) of last buffer in communication
calling. Making the last communication buffer size small is useful to
improve performance. Default: 1.
find_unused_parameters(bool, optional): Whether to traverse the entire backward graph from the
all tensors in the return value of the wrapped model's
forward function. For parameters not involved in loss
calculation, their gradients will be marked as ready in
advance to prepare reduce. Please note that all forward
outputs derived from the wrapped model parameters must
participate in the calculation of loss and subsequent
gradient calculations. If not, serious error will occur.
Note that setting the find_unused_parameters to True
will affect computing performance. Therefore, if all parameters
are sure to participate in the loss calculation and the
autograd graph construction, please set it False. Default: False.
Returns:
Layer: The data paralleled module.
Examples:
.. code-block:: pycon
:name: dp-example
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import paddle
>>> import paddle.nn as nn
>>> import paddle.optimizer as opt
>>> import paddle.distributed as dist
>>> class LinearNet(nn.Layer):
... def __init__(self):
... super().__init__()
... self._linear1 = nn.Linear(10, 10)
... self._linear2 = nn.Linear(10, 1)
...
... def forward(self, x):
... return self._linear2(self._linear1(x))
>>> def train():
... # 1. initialize parallel environment
... dist.init_parallel_env()
... # 2. create data parallel layer & optimizer
... layer = LinearNet()
... dp_layer = paddle.DataParallel(layer)
... loss_fn = nn.MSELoss()
... adam = opt.Adam(learning_rate=0.001, parameters=dp_layer.parameters())
... # 3. run layer
... inputs = paddle.randn([10, 10], 'float32')
... outputs = dp_layer(inputs)
... labels = paddle.randn([10, 1], 'float32')
... loss = loss_fn(outputs, labels)
... loss.backward()
... adam.step()
... adam.clear_grad()
>>> if __name__ == '__main__':
... # 1. start by ``paddle.distributed.spawn`` (default)
... dist.spawn(train, nprocs=2)
... # 2. start by ``paddle.distributed.launch``
... # train()
.. note::
``PyLayer`` is not supported in DataParallel. To solve problems of this kind,
it's recommended to skip gradient synchronization among multiple cards by 'no_sync',
and manually implement 'all_reduce' before model optimization. There is an example
showing specific implementation processing.
Examples:
.. code-block:: pycon
:name: dp-pylayer-example
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import numpy
>>> import paddle
>>> import paddle.distributed as dist
>>> from paddle.autograd import PyLayer
>>> from paddle.distributed.fleet.utils.hybrid_parallel_util import fused_allreduce_gradients
>>> class cus_tanh(PyLayer):
... @staticmethod
... def forward(ctx, x):
... y = paddle.tanh(x)
... ctx.save_for_backward(y)
... return y
...
... @staticmethod
... def backward(ctx, dy):
... (y,) = ctx.saved_tensor()
... grad = dy * (1 - paddle.square(y))
... return grad
>>> class SimpleNet(paddle.nn.Layer):
... def __init__(self):
... super().__init__()
... self.linear = paddle.nn.Linear(2, 2)
...
... def forward(self, inputs):
... inputs = cus_tanh.apply(inputs)
... return self.linear(inputs)
>>> if __name__ == '__main__':
... dist.init_parallel_env()
... model = SimpleNet()
... model = paddle.DataParallel(model)
... opt = paddle.optimizer.SGD(learning_rate=0.01, parameters=model.parameters())
... for step in range(10):
... x_data = numpy.random.randn(2, 2).astype(numpy.float32)
... x = paddle.to_tensor(x_data)
... x.stop_gradient = False
... # step 1 : skip gradient synchronization by 'no_sync'
... with model.no_sync():
... y_pred = model(x)
... loss = y_pred.mean()
... loss.backward()
... # step 2 : fuse + allreduce manually before optimization
... fused_allreduce_gradients(list(model.parameters()), None)
... opt.step()
... opt.clear_grad()
"""
find_unused_parameters: bool
grad_need_sync: bool
group: Group | None
var_dtype: Tensor
comm_buffer_size: int
last_comm_buffer_size: int
def __init__(
self,
layers: Layer,
strategy: ParallelStrategy | None = None,
comm_buffer_size: int = 25,
last_comm_buffer_size: float = 1,
find_unused_parameters: bool = False,
group: Group | None = None,
) -> None:
super().__init__(layers.full_name() + "_data_parallel")
assert in_dynamic_mode(), (
"It's not supported to construct DataParallel in static graph mode."
)
self._layers = layers
self.find_unused_parameters = find_unused_parameters
self.grad_need_sync = True
self.group = group
self.var_dtype = core.eager.Tensor
# NOTE(chenweihang): The ParallelStrategy here is not strictly a strategy.
# It just stores some environment variables, which can be constructed by
# ParallelEnv. Here it is set as an optional argument.
# This parameter is not removed because of compatibility with 1.x writing.
if strategy is not None:
self._strategy = strategy
else:
self._strategy = _build_default_parallel_strategy()
if self._strategy.nranks > 1:
# check the environment
assert parallel_helper.__parallel_ctx__clz__ is not None, (
"ParallelContext must be initialized before. You should use init_parallel_env() before"
"constructing the DataParallel."
)
if in_dynamic_mode():
self.group = (
paddle.distributed.collective._get_default_group()
if self.group is None
else self.group
)
assert isinstance(
self.group, paddle.distributed.collective.Group
), "ProcessGroup must be an instance of Group in DataParallel."
[
warnings.warn(
f"param [{name}] is not contiguous, please check it and make it contiguous."
)
for name, param in self._layers.named_parameters()
if not param.is_contiguous()
]
# sync buffer and params
sync_params_buffers(self._layers, fuse_params=False)
self.comm_buffer_size = int(comm_buffer_size * 1024 * 1024)
# NOTE(shenliang03): We can set environment variables to control
# the size of the group, Default: 1MB. The role of this small group is:
# when the last group allreduce, the overlap cannot work. Making the
# the last group small is useful to improve performance.
self.last_comm_buffer_size = int(
last_comm_buffer_size * 1024 * 1024
)
self.init_reducer()
else:
warnings.warn(
"The program will return to single-card operation. "
"Please check 1, whether you use spawn or fleetrun "
"to start the program. 2, Whether it is a multi-card "
"program. 3, Is the current environment multi-card."
)
def init_reducer(self) -> None:
layers_param = []
params_set = set()
for sublayer in self.sublayers():
for _, param in sublayer.named_parameters(include_sublayers=False):
if param is None or param in params_set:
continue
params_set.add(param)
if not isinstance(param, self.var_dtype):
raise TypeError(
f"The data type of '{param.name}' must be '{self.var_dtype}'"
)
if param.trainable:
layers_param.append((sublayer, param))
trainable_parameters = list(
filter(
lambda x: not getattr(x, "no_sync", False),
[param for _, param in layers_param],
)
)
assert len(trainable_parameters) > 0, (
"This model does not have any parameters to train, and "
"does not need to use DataParallel"
)
# NOTE(shenliang03): Here we can only use the attributes to judge whether
# parameter is sparse(or SelectedRows). The reason is that the sparse message
# can't be obtained when bp hasn't happened yet. So if layer supports sparse parameter,
# we should add the layer here like "paddle.nn.layer.common.Embedding".
def check_layer_sparse(sublayer):
if isinstance(sublayer, paddle.nn.layer.common.Embedding):
return sublayer._sparse
return False
is_sparse_gradient = [
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check_layer_sparse(sublayer)
for sublayer, param in layers_param
if not getattr(param, "no_sync", False)
]
if in_dynamic_mode():
self.group_indices = core.eager_assign_group_by_size(
trainable_parameters,
is_sparse_gradient,
[self.last_comm_buffer_size, self.comm_buffer_size],
)
self._reducer = core.EagerReducer(
trainable_parameters,
list(reversed(self.group_indices)),
is_sparse_gradient,
self.group.process_group,
[self.last_comm_buffer_size, self.comm_buffer_size],
self.find_unused_parameters,
)
def _find_tensor(self, obj):
var_type = core.eager.Tensor
if isinstance(obj, var_type):
return [obj]
if isinstance(obj, (list, tuple)):
return itertools.chain(*map(self._find_tensor, obj))
if isinstance(obj, dict):
return itertools.chain(*map(self._find_tensor, obj.values()))
return []
@contextmanager
def no_sync(self) -> Generator[None, None, None]:
"""
A context manager to stop gradient synchronization. Within no_sync(),
gradients of parameters will only be accumulated on model and not
synchronized util the first forward-backward out of this context.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import paddle
>>> import paddle.nn as nn
>>> import paddle.distributed as dist
>>> class SimpleNet(nn.Layer):
... def __init__(self):
... super().__init__()
... self._linear = nn.Linear(10, 1)
...
... def forward(self, x):
... return self._linear(x)
>>> dist.init_parallel_env()
>>> model = SimpleNet()
>>> dp_model = paddle.DataParallel(model)
>>> inputs_1 = paddle.randn([10, 10], 'float32')
>>> inputs_2 = paddle.ones([10, 10], 'float32')
>>> with dp_model.no_sync():
... # gradients will not be synchronized
... dp_model(inputs_1).backward()
>>> # synchronization happens here
>>> dp_model(inputs_2).backward()
"""
tmp_grad_need_sync = self.grad_need_sync
self.grad_need_sync = False
try:
yield
finally:
self.grad_need_sync = tmp_grad_need_sync
def forward(self, *inputs: Any, **kwargs: Any) -> Tensor:
outputs = self._layers(*inputs, **kwargs)
if (
self._strategy.nranks > 1
and framework._dygraph_tracer()._has_grad
and self.grad_need_sync
):
self._reducer.prepare_for_backward(list(self._find_tensor(outputs)))
return outputs
@deprecated(
since="2.0.0", reason="This method does not need to be called anymore."
)
def scale_loss(self, loss):
"""
Deprecated method, now ``scale_loss`` is an empty method,
keep this method just for compatibility.
"""
return loss
@deprecated(
since="2.0.0", reason="This method does not need to be called anymore."
)
def apply_collective_grads(self):
"""
Deprecated method, now ``apply_collective_grads`` is an empty method,
keep this method just for compatibility.
"""
return
def state_dict(
self,
destination: _StateDict | None = None,
include_sublayers: bool = True,
structured_name_prefix: str = "",
) -> _StateDict:
'''
Get all parameters and persistable buffers of current layer and its sub-layers. And set them into a dict
Parameters:
destination(dict, optional) : If provide, all the parameters and persistable buffers will be set to this dict . Default: None
include_sublayers(bool, optional) : If true, also include the parameters and persistable buffers from sublayers. Default: True
Returns:
dict: a dict contains all the parameters and persistable buffers.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import paddle
>>> import paddle.distributed as dist
>>> dist.init_parallel_env()
>>> emb = paddle.nn.Embedding(10, 10)
>>> emb = paddle.DataParallel(emb)
>>> state_dict = emb.state_dict()
>>> paddle.save(state_dict, "paddle_dy.pdparams")
'''
return self._layers.state_dict(
destination=destination,
include_sublayers=include_sublayers,
structured_name_prefix=structured_name_prefix,
)
@framework.deprecate_stat_dict
def set_state_dict(
self, state_dict: _StateDict, use_structured_name: bool = True
) -> None:
'''
Set parameters and persistable buffers from state_dict. All the parameters and buffers will be reset by the tensor in the state_dict
Parameters:
state_dict(dict) : Dict contains all the parameters and persistable buffers.
use_structured_name(bool, optional) : If true, use structured name as key, otherwise, use parameter or buffer name as key.
Default: True
Returns:
None
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import paddle
>>> import paddle.distributed as dist
>>> dist.init_parallel_env()
>>> emb = paddle.nn.Embedding(10, 10)
>>> emb = paddle.DataParallel(emb)
>>> state_dict = emb.state_dict()
>>> paddle.save(state_dict, "paddle_dy.pdparams")
>>> para_state_dict = paddle.load("paddle_dy.pdparams")
>>> emb.set_state_dict(para_state_dict)
'''
self._layers.set_state_dict(
state_dict, use_structured_name=use_structured_name
)
# [aliases] Compatible with old method names
set_dict = set_state_dict
load_dict = set_state_dict
# NOTE(chenweihang): Maintain a global parallel env to avoid
# initializing ParallelEnv every time and improve performance
_global_parallel_env = None
class ParallelEnv:
"""
.. note::
This API is not recommended, if you need to get rank and world_size,
it is recommended to use ``paddle.distributed.get_rank()`` and
``paddle.distributed.get_world_size()`` .
This class is used to obtain the environment variables required for
the parallel execution of ``paddle.nn.Layer`` in dynamic mode.
The parallel execution in dynamic mode needs to be started using ``paddle.distributed.launch``
or ``paddle.distributed.spawn`` .
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> import paddle
>>> import paddle.distributed as dist
>>> def train():
... # 1. initialize parallel environment
... dist.init_parallel_env()
... # 2. get current ParallelEnv
... parallel_env = dist.ParallelEnv()
... print("rank: ", parallel_env.rank)
... print("world_size: ", parallel_env.world_size)
>>> if __name__ == '__main__':
... # 1. start by ``paddle.distributed.spawn`` (default)
... dist.spawn(train, nprocs=2)
... # 2. start by ``paddle.distributed.launch``
... train()
# Print result in process 1:
rank: 1
world_size: 2
# Print result in process 2:
rank: 2
world_size: 2
"""
def __init__(self):
self._rank = int(os.getenv("PADDLE_TRAINER_ID", "0"))
self._world_size = int(os.getenv("PADDLE_TRAINERS_NUM", "1"))
custom_device_types = get_all_custom_device_type()
self._device_type = (
str(custom_device_types[0]) if custom_device_types else ""
)
self._pg_timeout = int(os.getenv("PADDLE_PG_TIMEOUT", "1800000"))
# imperative only support one gpu or xpu
if self._device_type != "":
FLAGS_selected_custom_devices = (
f'FLAGS_selected_{self._device_type}s'
)
selected_custom_devices = os.getenv(
FLAGS_selected_custom_devices, "0"
).split(",")
self._device_id = int(selected_custom_devices[0])
else:
if core.is_compiled_with_cuda():
selected_gpus = os.getenv("FLAGS_selected_gpus", "0").split(",")
self._device_id = int(selected_gpus[0])
elif core.is_compiled_with_xpu():
selected_xpus = os.getenv("FLAGS_selected_xpus", "0").split(",")
self._device_id = int(selected_xpus[0])
self._trainer_endpoints = getenv_or_backup(
"PADDLE_TRAINER_ENDPOINTS", ""
).split(",")
self._current_endpoint = os.getenv("PADDLE_CURRENT_ENDPOINT", "")
self._nrings = int(os.getenv("FLAGS_nccl_nrings", "1"))
assert self._nrings > 0, (
"nccl_nrings must be an integer greater than 0."
)
assert self._nrings < 9, (
"nccl_nrings should be less than 9, which is enough in most scenarios."
)
@property
def rank(self) -> int:
"""
Rank of current trainer.
Its value is equal to the value of the environment variable ``PADDLE_TRAINER_ID`` . The default value is 0.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export PADDLE_TRAINER_ID=0
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The rank is %d" % env.rank)
The rank is 0
"""
return self._rank
@property
def world_size(self) -> int:
"""
The number of trainers (number of processes participating in current job).
Its value is equal to the value of the environment variable ``PADDLE_TRAINERS_NUM`` . The default value is 1.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export PADDLE_TRAINERS_NUM=4
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The world_size is %d" % env.world_size)
The world_size is 4
"""
return self._world_size
@property
def device_id(self) -> int:
"""
The ID of selected GPU card for parallel training.
Its value is equal to the value of the environment variable ``FLAGS_selected_gpus`` . The default value is 0.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export FLAGS_selected_gpus=1
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The device id are %d" % env.device_id)
The device id are 1
"""
return self._device_id
@property
def device_type(self) -> str:
"""
The type of custom device for parallel training.
Its value is equal to the value of paddle.device.get_all_custom_device_type() . The default value is None.
"""
return self._device_type
@property
def current_endpoint(self) -> str:
"""
The endpoint of current trainer, it is in the form of (node IP + port).
Its value is equal to the value of the environment variable ``PADDLE_CURRENT_ENDPOINT`` . The default value is "".
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export PADDLE_CURRENT_ENDPOINT=127.0.0.1:6170
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The current endpoint are %s" % env.current_endpoint)
The current endpoint are 127.0.0.1:6170
"""
return self._current_endpoint
@property
def trainer_endpoints(self) -> list[str]:
"""
The endpoints of all trainer nodes in the task,
which are used to broadcast the NCCL ID when NCCL2 is initialized.
Its value is equal to the value of the environment variable ``PADDLE_TRAINER_ENDPOINTS`` . The default value is "".
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export PADDLE_TRAINER_ENDPOINTS=127.0.0.1:6170,127.0.0.1:6171
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The trainer endpoints are %s" % env.trainer_endpoints)
The trainer endpoints are ['127.0.0.1:6170', '127.0.0.1:6171']
"""
return self._trainer_endpoints
@property
def nrings(self) -> int:
"""
Nrings of current trainer.
Its value is equal to the value of the environment variable ``FLAGS_nccl_nrings`` . The default value is 1.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # execute this command in terminal: export FLAGS_nccl_nrings=1
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> print("The nrings is %d" % env.nrings)
The nrings is 1
"""
return self._nrings
@property
def pg_timeout(self) -> int:
"""
timeout of process group.
Its value is equal to the value of the environment variable ``PADDLE_PG_TIMEOUT`` . The default value is 30 minutes.
Examples:
.. code-block:: pycon
>>> # execute this command in terminal: export PADDLE_PG_TIMEOUT=1800000
>>> import paddle.distributed as dist
>>> env = dist.ParallelEnv()
>>> # the pg_timeout of process group 1800000
"""
return self._pg_timeout
# [aliases] Compatible with old method names
local_rank = rank
nranks = world_size
dev_id = device_id
def _get_global_parallel_env():
global _global_parallel_env
if _global_parallel_env is None:
_global_parallel_env = ParallelEnv()
return _global_parallel_env
def _start_kv_server(port, http_server_d, size):
from paddle.distributed.fleet.utils.http_server import KVServer
http_server = KVServer(int(port), size=size)
http_server.start()
wait_seconds = 3
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while http_server_d.get("running", False) or not http_server.should_stop():
time.sleep(wait_seconds)
http_server.stop()
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def _is_cpuonly(backend):
check_backend(backend)
if (
backend in ['auto', 'nccl', 'bkcl', 'heter', 'flagcx']
and (core.is_compiled_with_cuda() or core.is_compiled_with_xpu())
) or backend == 'xccl':
# passes 'auto' and can use cuda or xpu, use the default logics. so return False
return False
else:
return True
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def _check_var_exists(var_name):
var = getenv_or_backup(var_name, None)
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if var is None:
raise ValueError(
"paddle.distributed initialize error, "
f"environment variable {var_name} is needed, but not set."
)
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def _get_modified_flags():
ret = []
FLAGS = namedtuple('FLAGS', ['name', 'current_value', 'default_value'])
global_flags = core.globals()
for key in global_flags.keys():
value = global_flags.get(key)
default_value = global_flags.get_default(key)
if not value == default_value:
ret.append(FLAGS(key, value, default_value))
return ret
def _print_modified_flags(modified_flags):
if len(modified_flags) > 0:
sys.stderr.write(
"======================= Modified FLAGS detected =======================\n"
)
for flag in modified_flags:
sys.stderr.write(str(flag))
sys.stderr.write("\n")
sys.stderr.write(
"=======================================================================\n"
)
def init_parallel_env(nccl_config: NCCLConfig | None = None) -> Group:
"""
Initialize parallel training environment in dynamic graph mode.
Fix the En docs (delete some expression like 'This OP') (#46165) * 1. Delete some expression like 'This Op' 2. remove import numpy as np * test=document_fix * fix eg; test=document_fix * fix 'import numpy' cases; test=document_fix * fix 'import numpy' cases; test=document_fix * fix some docs; test=document_fix * delete raise; test=document_fix * add some introduction; test=document_fix * add some introduction; test=document_fix * test=document_fix * Fix ’note‘ format; test=document_fix * Fix Returns of cholesky; test=document_fix * Fix Example format; test=document_fix * Fix det; test=document_fix * Fix eig; test=document_fix * Fix eigh; test=document_fix * Fix eigh; test=document_fix * Apply suggestions from code review;test = document_fix Co-authored-by: Nyakku Shigure <sigure.qaq@gmail.com> * Apply suggestions from code review;test = document_fix Co-authored-by: Nyakku Shigure <sigure.qaq@gmail.com> * Apply suggestions from code review;test = document_fix Co-authored-by: Nyakku Shigure <sigure.qaq@gmail.com> * test=document_fix * test=document_fix * KLDiv;test=document_fix * norm example code; test=document_fix * revert python/paddle/fluid/**/* * revert python/paddle/distributed/spawn.py * revert python/paddle/fluid/* * fix a `Note` format * Fix inv; test=document_fix * Fix lu; test=document_fix * Fix lu_unpack; test=document_fix * Fix matrix_power; test=document_fix * Fix multi_dot; test=document_fix * Fix solve; test=document_fix Co-authored-by: Nyakku Shigure <sigure.qaq@gmail.com>
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Note:
Now initialize both `NCCL` and `GLOO` contexts for communication.
Args:
backend (string): A string represents the backend used by DataParallel,
should be one of 'gloo'(for cpu), 'nccl'(for cuda), 'bkcl'(for xpu), 'auto'(auto detect).
The auto detection prefer 'nccl', 'bkcl' than 'gloo'.
Returns:
None
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:GPU, env:DISTRIBUTED)
>>> import paddle
>>> import paddle.nn as nn
>>> import paddle.optimizer as opt
>>> import paddle.distributed as dist
>>> class LinearNet(nn.Layer):
... def __init__(self):
... super().__init__()
... self._linear1 = nn.Linear(10, 10)
... self._linear2 = nn.Linear(10, 1)
...
... def forward(self, x):
... return self._linear2(self._linear1(x))
>>> def train():
... # 1. initialize parallel environment
... dist.init_parallel_env()
... # 2. create data parallel layer & optimizer
... layer = LinearNet()
... dp_layer = paddle.DataParallel(layer)
... loss_fn = nn.MSELoss()
... adam = opt.Adam(learning_rate=0.001, parameters=dp_layer.parameters())
... # 3. run layer
... inputs = paddle.randn([10, 10], 'float32')
... outputs = dp_layer(inputs)
... labels = paddle.randn([10, 1], 'float32')
... loss = loss_fn(outputs, labels)
... loss.backward()
... adam.step()
... adam.clear_grad()
>>> if __name__ == '__main__':
... dist.spawn(train)
"""
modified_flags = _get_modified_flags()
_print_modified_flags(modified_flags)
# 0. get env & check world size
global _global_parallel_env
# when call init_parallel_env, need update `_global_parallel_env`
_global_parallel_env = ParallelEnv()
parallel_env = _global_parallel_env
# if not parallel, `init_parallel_env` do nothing
if parallel_env.world_size < 2:
warnings.warn(
"Currently not a parallel execution environment, `paddle.distributed.init_parallel_env` will not do anything."
)
return
# NOTE(xiongkun): support cpu gloo only, add this environment variable to
# enable cpu only gloo parallel training)
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backend = os.environ.get('PADDLE_DISTRI_BACKEND', 'auto')
# if we want to use flagcx as backend in xpu environment, we need to
# set backend to bkcl, and process_group_bkcl will internally invoke
# flagcx to perform communication tasks
if backend == "flagcx" and core.is_compiled_with_xpu():
os.environ['PADDLE_DISTRI_BACKEND'] = "bkcl"
backend = "bkcl"
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is_cpu_only = _is_cpuonly(backend)
# 1. gpu xpu check, must be gpu or xpu,
if not (
is_cpu_only
or core.is_compiled_with_cuda()
or core.is_compiled_with_xpu()
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or backend == "xccl"
):
raise NotImplementedError(
"If you want to use CPU-only version, please use 'gloo' as backend"
)
if backend == "xccl":
FLAGS_selected_custom_devices = (
f'FLAGS_selected_{parallel_env.device_type}s'
)
_check_var_exists(FLAGS_selected_custom_devices)
else:
if not is_cpu_only and core.is_compiled_with_cuda():
_check_var_exists("FLAGS_selected_gpus")
backend = "nccl" if backend == "auto" else backend
elif not is_cpu_only and core.is_compiled_with_xpu():
_check_var_exists('FLAGS_selected_xpus')
backend = "bkcl" if backend == "auto" else backend
_check_var_exists("PADDLE_TRAINER_ID")
_check_var_exists("PADDLE_CURRENT_ENDPOINT")
_check_var_exists("PADDLE_TRAINERS_NUM")
# NOTE(chenweihang): [ why config global place here? ]
# the dygraph mode will be set to default mode,
# users will not call `dygraph.guard` or `enable_dygraph`
# directly, if they want to switch default place,
# they need to call a function to change default place,
# here just set correctly place to users
if backend == "xccl":
place = core.CustomPlace(
parallel_env.device_type, parallel_env.device_id
)
elif is_cpu_only:
place = core.CPUPlace()
elif core.is_compiled_with_cuda():
place = core.CUDAPlace(parallel_env.device_id)
elif core.is_compiled_with_xpu():
place = core.XPUPlace(parallel_env.device_id)
_set_expected_place(place)
group = None
if backend in _valid_backend_list and in_dynamic_mode():
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if _default_group_name in _get_group_map_by_name():
return _get_group_map_by_name()[_default_group_name]
_set_default_backend(backend)
rank = int(os.getenv("PADDLE_TRAINER_ID"))
world_size = int(os.getenv("PADDLE_TRAINERS_NUM"))
assert rank >= 0 and world_size > rank and world_size > 1, (
"rank must be non-negative and world_size must be the "
"maximum rank plus one. Moreover, at least two processes are "
"required to create a process group."
)
master_addr = os.getenv("MASTER_ADDR", None)
master_port = os.getenv("MASTER_PORT", None)
endpoints = (
":".join([master_addr, master_port])
if master_addr and master_port
else None
)
if endpoints is None:
endpoints = os.getenv("PADDLE_MASTER", None)
if endpoints is None:
endpoints = getenv_or_backup("PADDLE_TRAINER_ENDPOINTS").split(',')[
0
]
assert endpoints, (
"The environment variable 'MASTER_ADDR' and 'MASTER_PORT' "
"must be specified, for example 'export MASTER_ADDR=127.0.0.1' "
"and 'export MASTER_ADDR=54612'. Or you can start your training"
"with paddle.distributed.run module."
)
master_addr, master_port = endpoints.split(":")
master_port = int(master_port)
is_master = rank == 0
stop_check_timeout = int(os.getenv("FLAGS_stop_check_timeout", "900"))
default_store = core.create_or_get_global_tcp_store()
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_set_default_store(default_store)
if backend in ["nccl", 'xccl', 'bkcl', 'flagcx']:
core.CommContextManager.set_device_id(parallel_env.device_id)
from paddle.distributed.fleet.base.topology import (
message2nccl_config,
)
pg = _new_process_group_impl(
backend,
default_store,
rank,
world_size,
_default_group_name,
pg_options=None,
nccl_config=message2nccl_config(
nccl_config,
"default",
),
)
ranks = list(range(world_size))
group = Group(rank, 0, ranks, pg=pg, name=_default_group_name)
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_set_group_map_by_name(_default_group_name, group)
_set_group_map(0, group)
_set_group_map_backend(group, backend)
_add_new_group(group)
parallel_helper._set_parallel_ctx(True)
return group
node_num = {i.split(":")[0] for i in parallel_env.trainer_endpoints}
# 3: init gloo context (step 1: httpserver start)
init_gloo = int(os.getenv("PADDLE_WITH_GLOO", "0"))
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if is_cpu_only or init_gloo or backend == "heter":
ep_rank_0 = parallel_env.trainer_endpoints[0].split(":")
manager = Manager()
# global dict to store status
http_server_d = manager.dict()
http_server_d["running"] = False
if parallel_env.rank == 0:
# The scope for worker used by http server is '_worker'
size = {'_worker': parallel_env.world_size}
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if backend == "heter":
size = {'_worker': len(node_num)}
http_server = Process(
target=_start_kv_server,
args=(int(ep_rank_0[1]), http_server_d, size),
)
http_server.daemon = True
http_server_d["running"] = True
http_server.start()
# 4. init NCCL ParallelStrategy
strategy = ParallelStrategy()
if parallel_helper._is_parallel_ctx_initialized():
warnings.warn("The parallel environment has been initialized.")
strategy.nranks = parallel_env.world_size
strategy.local_rank = parallel_env.rank
strategy.trainer_endpoints = parallel_env.trainer_endpoints
strategy.current_endpoint = parallel_env.current_endpoint
strategy.nrings = parallel_env.nrings
# init nccl or bkcl or heter context
if is_cpu_only:
parallel_helper._set_parallel_ctx(
core.GLOOParallelContext(strategy, place)
)
elif backend == "heter":
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parallel_helper._set_parallel_ctx(
core.HeterParallelContext(strategy, parallel_env.device_id)
)
elif core.is_compiled_with_cuda():
parallel_helper._set_parallel_ctx(
core.NCCLParallelContext(strategy, place)
)
elif core.is_compiled_with_xpu():
parallel_helper._set_parallel_ctx(
core.BKCLParallelContext(strategy, place)
)
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if backend != "heter":
other_endpoints = strategy.trainer_endpoints[:]
other_endpoints.remove(strategy.current_endpoint)
if not is_cpu_only and strategy.local_rank == 0:
wait_server_ready(other_endpoints)
parallel_helper._init_parallel_ctx()
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# 5: init gloo context (step 2: gloo init)
# dividing init_gloo into two part because nccl and gloo
# are separately looking for free ports which sometimes
# leads to port-conflict.
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if (is_cpu_only or backend == "heter") and parallel_env.rank == 0:
# compare to init_gloo, we don't need to
# init gloo, because we do this in _init_parallel_ctx;
http_server_d["running"] = False
http_server.join()
elif init_gloo:
wait_server_ready([parallel_env.trainer_endpoints[0]])
gloo_strategy = core.GlooParallelStrategy()
gloo_strategy.rank = parallel_env.rank
gloo_strategy.rank_num = parallel_env.world_size
gloo_strategy.ip_address = ep_rank_0[0]
gloo_strategy.ip_port = int(ep_rank_0[1])
default_init_timeout_seconds = 3600
default_run_timeout_seconds = 9999999
gloo_strategy.init_seconds = default_init_timeout_seconds
gloo_strategy.run_seconds = default_run_timeout_seconds
gloo = core.GlooParallelContext(gloo_strategy)
gloo.init()
if parallel_env.rank == 0:
http_server_d["running"] = False
http_server.join()
return group
def get_rank(group: Group | None = None) -> int:
"""
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Returns the rank of current trainer in the given group, ranks are consecutive integers in [0, ``world_size``).
If none of the group is given, the global group will be used as default.
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Args:
group (Group, optional): The communication group you want to get rank of current trainer, use global group as default if group is None.
Returns:
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(int) The rank of current trainer in the given group. Return -1 if the process is not part of the given group.
Warning:
Argument ``group`` only supports in dygraph mode.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # Execute this script using distributed launch with one card configs.
>>> import paddle
>>> import paddle.distributed as dist
>>> dist.init_parallel_env()
>>> print("The rank is %d" % dist.get_rank())
The rank is 0
"""
if in_dynamic_mode() and group:
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return group.rank
assert group is None, "Only support group argument in eager mode."
return _get_global_parallel_env().rank
def get_world_size(group: Group | None = None) -> int:
"""
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Returns the number of trainers (number of processes participating in current job) in the given group.
If none of the group is given, the global group will be used as default.
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Args:
group (Group, optional): The communication group you want to check world size, use global group as default if group is None.
Returns:
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(int) The number of trainers in the given group. Return -1 if the process if not part of the given group.
Warning:
Argument ``group`` only supports in dygraph mode.
Examples:
.. code-block:: pycon
>>> # doctest: +REQUIRES(env:DISTRIBUTED)
>>> # Execute this script using distributed launch with one card configs.
>>> import paddle
>>> import paddle.distributed as dist
>>> dist.init_parallel_env()
>>> print("The world_size is %d" % dist.get_world_size())
The world_size is 1
"""
if in_dynamic_mode() and (group is None):
if is_initialized():
group = _get_global_group()
if in_dynamic_mode() and group:
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return group.world_size
assert group is None, "Only support group argument in eager mode."
return _get_global_parallel_env().world_size