Add SyncBatchNorm

paddle/fluid/pybind/op_function_generator.cc

@@ -56,6 +56,9 @@ std::map<std::string, std::set<std::string>> op_outs_map = {
     {"batch_norm",
      {"Y", "MeanOut", "VarianceOut", "SavedMean", "SavedVariance",
       "ReserveSpace"}},
+    {"sync_batch_norm",
+     {"Y", "MeanOut", "VarianceOut", "SavedMean", "SavedVariance",
+      "ReserveSpace"}},
 };
 
 // NOTE(zhiqiu): Commonly, the outputs in auto-generated OP function are
@@ -75,6 +78,7 @@ std::map<std::string, std::set<std::string>> op_passing_outs_map = {
      {"ParamOut", "Moment1Out", "Moment2Out", "Beta1PowOut", "Beta2PowOut"}},
     {"momentum", {"ParamOut", "VelocityOut"}},
     {"batch_norm", {"MeanOut", "VarianceOut"}},
+    {"sync_batch_norm", {"MeanOut", "VarianceOut"}},
     {"accuracy", {"Correct", "Total"}},
     {"fill_constant", {"Out"}},
     {"matmul", {"Out"}},

python/paddle/fluid/dygraph/nn.py

@@ -35,7 +35,7 @@
     'Conv2D', 'Conv3D', 'Pool2D', 'Linear', 'BatchNorm', 'Dropout', 'Embedding',
     'GRUUnit', 'InstanceNorm', 'LayerNorm', 'NCE', 'PRelu',
     'BilinearTensorProduct', 'Conv2DTranspose', 'Conv3DTranspose', 'GroupNorm',
-    'SpectralNorm', 'TreeConv', 'Flatten'
+    'SpectralNorm', 'TreeConv', 'Flatten', 'SyncBatchNorm'
 ]
 
 
@@ -3184,6 +3184,214 @@ def forward(self, nodes_vector, edge_set):
         return self._helper.append_activation(pre_activation, act=self._act)
 
 
+class SyncBatchNorm(layers.Layer):
+    """
+    :alias_main: paddle.nn.SyncBatchNorm
+	:alias: paddle.nn.SyncBatchNorm,paddle.nn.layer.SyncBatchNorm,paddle.nn.layer.norm.SyncBatchNorm
+	:old_api: paddle.fluid.dygraph.SyncBatchNorm
+
+    This interface is used to construct a callable object of the ``SyncBatchNorm`` class.
+    It implements the function of the Cross-GPU Synchronized Batch Normalization Layer, and can 
+    be used as a normalizer function for other operations, such as conv2d and fully connected 
+    operations.
+    The data is normalized by the mean and variance of the channel based on whole mini-batch
+    , which including data in all gpus.
+    Refer to `Batch Normalization: Accelerating Deep Network Training by Reducing
+    Internal Covariate Shift <https://arxiv.org/pdf/1502.03167.pdf>`_
+    for more details.
+
+    When model in train mode, the :math:`\\mu_{\\beta}` 
+    and :math:`\\sigma_{\\beta}^{2}` are the statistics of whole mini-batch data in all gpus.
+    Calculated as follows:
+
+    ..  math::
+
+        \\mu_{\\beta} &\\gets \\frac{1}{m} \\sum_{i=1}^{m} x_i \\qquad &//\\
+        \ mini-batch\ mean \\\\
+        \\sigma_{\\beta}^{2} &\\gets \\frac{1}{m} \\sum_{i=1}^{m}(x_i - \\
+        \\mu_{\\beta})^2 \\qquad &//\ mini-batch\ variance \\\\
+
+    - :math:`x` : mini-batch data
+    - :math:`m` : the size of the mini-batch data
+
+    When model in eval mode, the :math:`\\mu_{\\beta}`
+    and :math:`\\sigma_{\\beta}^{2}` are global or running statistics (moving_mean and moving_variance). 
+    It usually got from the pre-trained model. Calculated as follows:
+
+    .. math::
+        moving\_mean = moving\_mean * momentum + \mu_{\beta} * (1. - momentum) \quad &// global mean \\
+        moving\_variance = moving\_variance * momentum + \sigma_{\beta}^{2} * (1. - momentum) \quad &// global variance \\
+
+    The normalization function formula is as follows:
+
+    ..  math::
+
+        \\hat{x_i} &\\gets \\frac{x_i - \\mu_\\beta} {\\sqrt{\\
+        \\sigma_{\\beta}^{2} + \\eps}} \\qquad &//\ normalize \\\\
+        y_i &\\gets \\gamma \\hat{x_i} + \\beta \\qquad &//\ scale\ and\ shift
+
+    - :math:`\\eps` : add a smaller value to the variance to prevent division by zero
+    - :math:`\\gamma` : trainable proportional parameter
+    - :math:`\\beta` : trainable deviation parameter
+
+    **Note**:
+        moving mean and moving variance will be calculate whether `track_running_stats` is set to `True`
+        or `False`, we will fix it in the next time.
+
+    Parameters:
+        num_features(int): Indicate the number of channels of the input ``Tensor``.
+        eps(float, optional): The small value added to the variance to prevent division by zero. Default: 1e-5.
+        momentum(float, optional): The value used for the moving_mean and moving_var computation. Default: 0.9.
+        scale_attr(ParamAttr, optional): The parameter attribute for Parameter `scale`
+             of batch_norm. If it is set to None or one attribute of ParamAttr, batch_norm
+             will create ParamAttr as param_attr. If the Initializer of the param_attr
+             is not set, the parameter is initialized with Xavier. Default: None.
+        bias_attr(ParamAttr, optional): The parameter attribute for the bias of batch_norm.
+             If it is set to None or one attribute of ParamAttr, batch_norm
+             will create ParamAttr as bias_attr. If the Initializer of the bias_attr
+             is not set, the bias is initialized zero. Default: None.
+        track_running_stats(bool, optional): Whether to compute global stats, which including running mean and 
+             running variance. Default: True.
+
+    Returns:
+        None
+
+    Examples:
+        .. code-block:: python
+
+          import paddle.nn as nn
+          import paddle.fluid as fluid
+          from paddle.fluid.dygraph import to_variable
+          import numpy as np
+
+          x = np.random.random(size=(3, 10, 3, 7)).astype('float32')
+          with fluid.dygraph.guard():
+              x = to_variable(x)
+              if fluid.is_compiled_with_cuda():
+                  sync_batch_norm = nn.SyncBatchNorm(10)
+                  hidden1 = sync_batch_norm(x)
+    """
+
+    def __init__(self,
+                 num_features,
+                 eps=1e-05,
+                 momentum=0.9,
+                 track_running_stats=True,
+                 scale_attr=None,
+                 bias_attr=None,
+                 name=None):
+        super(SyncBatchNorm, self).__init__()
+        self._scale_attr = scale_attr
+        self._bias_attr = bias_attr
+
+        assert bias_attr is not False, "bias_attr should not be False in batch_norm."
+
+        self._dtype = "float32"
+
+        param_shape = [num_features]
+
+        # create parameter
+        self.weight = self.create_parameter(
+            attr=self._scale_attr,
+            shape=param_shape,
+            dtype=self._dtype,
+            default_initializer=Constant(1.0))
+        self.weight.stop_gradient = self._scale_attr != None and self._scale_attr.learning_rate == 0.
+
+        self.bias = self.create_parameter(
+            attr=self._bias_attr,
+            shape=param_shape,
+            dtype=self._dtype,
+            is_bias=True)
+        self.bias.stop_gradient = self._scale_attr != None and self._scale_attr.learning_rate == 0.
+
+        self._mean = self.create_parameter(
+            attr=ParamAttr(
+                name=None,
+                initializer=Constant(0.0),
+                trainable=False,
+                do_model_average=False),
+            shape=param_shape,
+            dtype=self._dtype)
+        self._mean.stop_gradient = True
+
+        self._variance = self.create_parameter(
+            attr=ParamAttr(
+                name=None,
+                initializer=Constant(1.0),
+                trainable=False,
+                do_model_average=False),
+            shape=param_shape,
+            dtype=self._dtype)
+        self._variance.stop_gradient = True
+
+        self._data_layout = 'NCHW'
+        self._momentum = momentum
+        self._eps = eps
+        self._track_running_stats = track_running_stats
+
+    def forward(self, input):
+        # create output
+        # mean and mean_out share the same memory
+        mean_out = self._mean
+        # variance and variance out share the same memory
+        variance_out = self._variance
+
+        ### train mode: use mini-batch stats, eval mode: use global stats
+        if in_dygraph_mode():
+            attrs = ("momentum", self._momentum, "epsilon", self._eps,
+                     "is_test", not self.training, "data_layout",
+                     self._data_layout, "use_mkldnn", False, "fuse_with_relu",
+                     False, "use_global_stats", not self.training,
+                     'trainable_statistics', False)
+            sync_batch_norm_out, _, _, _, _, _ = core.ops.sync_batch_norm(
+                input, self.weight, self.bias, self._mean, self._variance,
+                mean_out, variance_out, *attrs)
+
+            return sync_batch_norm_out
+
+        check_variable_and_dtype(input, 'input',
+                                 ['float16', 'float32', 'float64'], 'BatchNorm')
+
+        attrs = {
+            "momentum": self._momentum,
+            "epsilon": self._eps,
+            "is_test": not self.training,
+            "data_layout": self._data_layout,
+            "use_mkldnn": False,
+            "fuse_with_relu": False,
+            "use_global_stats": not self.training,
+            "trainable_statistics": False,
+        }
+
+        inputs = {
+            "X": [input],
+            "Scale": [self.weight],
+            "Bias": [self.bias],
+            "Mean": [self._mean],
+            "Variance": [self._variance]
+        }
+
+        saved_mean = self._helper.create_variable_for_type_inference(
+            dtype=self._dtype, stop_gradient=True)
+        saved_variance = self._helper.create_variable_for_type_inference(
+            dtype=self._dtype, stop_gradient=True)
+        sync_batch_norm_out = self._helper.create_variable_for_type_inference(
+            self._dtype)
+
+        outputs = {
+            "Y": [sync_batch_norm_out],
+            "MeanOut": [mean_out],
+            "VarianceOut": [variance_out],
+            "SavedMean": [saved_mean],
+            "SavedVariance": [saved_variance]
+        }
+
+        self._helper.append_op(
+            type="sync_batch_norm", inputs=inputs, outputs=outputs, attrs=attrs)
+        return sync_batch_norm_out
+
+
 class Flatten(layers.Layer):
     """
     :alias_main: paddle.nn.Flatten

python/paddle/fluid/tests/unittests/CMakeLists.txt

@@ -100,6 +100,8 @@ if (NOT ${WITH_GPU})
     list(REMOVE_ITEM TEST_OPS test_parallel_dygraph_se_resnext)
     LIST(REMOVE_ITEM TEST_OPS test_parallel_dygraph_sparse_embedding)
     LIST(REMOVE_ITEM TEST_OPS test_parallel_dygraph_transformer)
+    LIST(REMOVE_ITEM TEST_OPS test_parallel_dygraph_sync_batch_norm)
+
 elseif(${CUDNN_VERSION} VERSION_LESS 7100)
     LIST(REMOVE_ITEM TEST_OPS test_conv2d_fusion_op)
 endif()

python/paddle/fluid/tests/unittests/parallel_dygraph_sync_batch_norm.py

@@ -0,0 +1,90 @@
+# Copyright (c) 2018 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 contextlib
+import unittest
+import numpy as np
+import six
+import pickle
+
+import paddle
+import paddle.fluid as fluid
+import paddle.fluid.dygraph as dygraph
+from paddle.fluid import core
+from paddle.fluid.optimizer import SGDOptimizer
+from paddle.nn import Conv2D, Pool2D, Linear, SyncBatchNorm
+from paddle.fluid.dygraph.base import to_variable
+
+from test_dist_base import runtime_main, TestParallelDyGraphRunnerBase
+
+
+class TestLayer(fluid.dygraph.Layer):
+    def __init__(self,
+                 num_channels,
+                 num_filters,
+                 filter_size,
+                 stride=1,
+                 groups=1,
+                 act=None):
+        super(TestLayer, self).__init__()
+
+        self._conv = Conv2D(
+            num_channels=num_channels,
+            num_filters=num_filters,
+            filter_size=filter_size,
+            stride=stride,
+            padding=(filter_size - 1) // 2,
+            groups=groups,
+            act=None,
+            bias_attr=False)
+
+        self._sync_batch_norm = SyncBatchNorm(num_filters)
+
+    def forward(self, inputs):
+        y = self._conv(inputs)
+        y = self._sync_batch_norm(y)
+
+        return y
+
+
+class TestSyncBatchNorm(TestParallelDyGraphRunnerBase):
+    def get_model(self):
+        model = TestLayer(3, 64, 7)
+        train_reader = paddle.batch(
+            paddle.dataset.flowers.test(use_xmap=False),
+            batch_size=32,
+            drop_last=True)
+        opt = fluid.optimizer.Adam(
+            learning_rate=1e-3, parameter_list=model.parameters())
+        return model, train_reader, opt
+
+    def run_one_loop(self, model, opt, data):
+        batch_size = len(data)
+        dy_x_data = np.array([x[0].reshape(3, 224, 224)
+                              for x in data]).astype('float32')
+        img = to_variable(dy_x_data)
+        img.stop_gradient = False
+
+        out = model(img)
+
+        out = fluid.layers.mean(out)
+
+        return out
+
+
+if __name__ == "__main__":
+    runtime_main(TestSyncBatchNorm)

python/paddle/fluid/tests/unittests/test_layers.py

@@ -283,6 +283,24 @@ def test_layer_norm(self):
             with self.assertRaises(ValueError):
                 lm(base.to_variable(inp))
 
+    def test_SyncBatchNorm(self):
+        if core.is_compiled_with_cuda():
+            with self.static_graph():
+                t = layers.data(name='t', shape=[-1, 3, 5, 5], dtype='float32')
+                my_sync_bn = nn.SyncBatchNorm(3)
+                ret = my_sync_bn(t)
+                static_ret = self.get_static_graph_result(
+                    feed={'t': np.ones(
+                        [3, 3, 5, 5], dtype='float32')},
+                    fetch_list=[ret])[0]
+
+            with self.dynamic_graph():
+                t = np.ones([3, 3, 5, 5], dtype='float32')
+                my_syncbn = paddle.nn.SyncBatchNorm(3)
+                dy_ret = my_syncbn(base.to_variable(t))
+                dy_ret_value = dy_ret.numpy()
+            self.assertTrue(np.array_equal(static_ret, static_ret))
+
     def test_relu(self):
         with self.static_graph():
             t = layers.data(name='t', shape=[3, 3], dtype='float32')