def testCreateOnecloneWithPS(self): g = tf.Graph() with g.as_default(): tf.set_random_seed(0) tf_inputs = tf.constant(self._inputs, dtype=tf.float32) tf_labels = tf.constant(self._labels, dtype=tf.float32) model_fn = BatchNormClassifier model_args = (tf_inputs, tf_labels) deploy_config = model_deploy.DeploymentConfig(num_clones=1, num_ps_tasks=1) self.assertEqual(slim.get_variables(), []) clones = model_deploy.create_clones(deploy_config, model_fn, model_args) self.assertEqual(len(slim.get_variables()), 5) update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS) self.assertEqual(len(update_ops), 2) optimizer = tf.train.GradientDescentOptimizer(learning_rate=1.0) total_loss, grads_and_vars = model_deploy.optimize_clones( clones, optimizer) self.assertEqual(len(grads_and_vars), len(tf.trainable_variables())) self.assertEqual(total_loss.op.name, 'total_loss') for g, v in grads_and_vars: self.assertDeviceEqual(g.device, '/job:worker/device:GPU:0') self.assertDeviceEqual(v.device, '/job:ps/task:0/CPU:0')
def testCreateMulticloneWithPS(self): g = tf.Graph() with g.as_default(): tf.set_random_seed(0) tf_inputs = tf.constant(self._inputs, dtype=tf.float32) tf_labels = tf.constant(self._labels, dtype=tf.float32) model_fn = BatchNormClassifier clone_args = (tf_inputs, tf_labels) deploy_config = model_deploy.DeploymentConfig(num_clones=2, num_ps_tasks=2) self.assertEqual(slim.get_variables(), []) clones = model_deploy.create_clones(deploy_config, model_fn, clone_args) self.assertEqual(len(slim.get_variables()), 5) for i, v in enumerate(slim.get_variables()): t = i % 2 self.assertDeviceEqual(v.device, '/job:ps/task:%d/device:CPU:0' % t) self.assertDeviceEqual(v.device, v.value().device) self.assertEqual(len(clones), 2) for i, clone in enumerate(clones): self.assertEqual( clone.outputs.op.name, 'clone_%d/BatchNormClassifier/fully_connected/Sigmoid' % i) self.assertEqual(clone.scope, 'clone_%d/' % i) self.assertDeviceEqual(clone.device, '/job:worker/device:GPU:%d' % i)
def testCreateOnecloneWithPS(self): g = tf.Graph() with g.as_default(): tf.set_random_seed(0) tf_inputs = tf.constant(self._inputs, dtype=tf.float32) tf_labels = tf.constant(self._labels, dtype=tf.float32) model_fn = BatchNormClassifier clone_args = (tf_inputs, tf_labels) deploy_config = model_deploy.DeploymentConfig(num_clones=1, num_ps_tasks=1) self.assertEqual(slim.get_variables(), []) clones = model_deploy.create_clones(deploy_config, model_fn, clone_args) self.assertEqual(len(clones), 1) clone = clones[0] self.assertEqual(clone.outputs.op.name, 'BatchNormClassifier/fully_connected/Sigmoid') self.assertDeviceEqual(clone.device, '/job:worker/device:GPU:0') self.assertEqual(clone.scope, '') self.assertEqual(len(slim.get_variables()), 5) for v in slim.get_variables(): self.assertDeviceEqual(v.device, '/job:ps/task:0/CPU:0') self.assertDeviceEqual(v.device, v.value().device)
def testCreateMulticlone(self): g = tf.Graph() with g.as_default(): tf.set_random_seed(0) tf_inputs = tf.constant(self._inputs, dtype=tf.float32) tf_labels = tf.constant(self._labels, dtype=tf.float32) model_fn = BatchNormClassifier clone_args = (tf_inputs, tf_labels) num_clones = 4 deploy_config = model_deploy.DeploymentConfig( num_clones=num_clones) self.assertEqual(slim.get_variables(), []) clones = model_deploy.create_clones(deploy_config, model_fn, clone_args) self.assertEqual(len(slim.get_variables()), 5) for v in slim.get_variables(): self.assertDeviceEqual(v.device, 'CPU:0') self.assertDeviceEqual(v.value().device, 'CPU:0') self.assertEqual(len(clones), num_clones) for i, clone in enumerate(clones): self.assertEqual( clone.outputs.op.name, 'clone_%d/BatchNormClassifier/fully_connected/Sigmoid' % i) update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS, clone.scope) self.assertEqual(len(update_ops), 2) self.assertEqual(clone.scope, 'clone_%d/' % i) self.assertDeviceEqual(clone.device, 'GPU:%d' % i)
def testCreateLogisticClassifier(self): g = tf.Graph() with g.as_default(): tf.set_random_seed(0) tf_inputs = tf.constant(self._inputs, dtype=tf.float32) tf_labels = tf.constant(self._labels, dtype=tf.float32) model_fn = LogisticClassifier clone_args = (tf_inputs, tf_labels) deploy_config = model_deploy.DeploymentConfig(num_clones=1) self.assertEqual(slim.get_variables(), []) clones = model_deploy.create_clones(deploy_config, model_fn, clone_args) clone = clones[0] self.assertEqual(len(slim.get_variables()), 2) for v in slim.get_variables(): self.assertDeviceEqual(v.device, 'CPU:0') self.assertDeviceEqual(v.value().device, 'CPU:0') self.assertEqual(clone.outputs.op.name, 'LogisticClassifier/fully_connected/Sigmoid') self.assertEqual(clone.scope, '') self.assertDeviceEqual(clone.device, 'GPU:0') self.assertEqual(len(slim.losses.get_losses()), 1) update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS) self.assertEqual(update_ops, [])
def main(_): if not FLAGS.dataset_dir: raise ValueError( 'You must supply the dataset directory with --dataset_dir') tf.logging.set_verbosity(tf.logging.INFO) with tf.Graph().as_default(): ####################### # Config model_deploy # ####################### deploy_config = model_deploy.DeploymentConfig( num_clones=FLAGS.num_clones, clone_on_cpu=FLAGS.clone_on_cpu, replica_id=FLAGS.task, num_replicas=FLAGS.worker_replicas, num_ps_tasks=FLAGS.num_ps_tasks) # Create global_step with tf.device(deploy_config.variables_device()): global_step = slim.create_global_step() ###################### # Select the dataset # ###################### dataset = dataset_factory.get_dataset(FLAGS.dataset_name, FLAGS.dataset_split_name, FLAGS.dataset_dir) ###################### # Select the network # ###################### network_fn = nets_factory.get_network_fn( FLAGS.model_name, num_classes=(dataset.num_classes - FLAGS.labels_offset), weight_decay=FLAGS.weight_decay, is_training=True) ##################################### # Select the preprocessing function # ##################################### preprocessing_name = FLAGS.preprocessing_name or FLAGS.model_name image_preprocessing_fn = preprocessing_factory.get_preprocessing( preprocessing_name, is_training=True) ############################################################## # Create a dataset provider that loads data from the dataset # ############################################################## with tf.device(deploy_config.inputs_device()): provider = slim.dataset_data_provider.DatasetDataProvider( dataset, num_readers=FLAGS.num_readers, common_queue_capacity=20 * FLAGS.batch_size, common_queue_min=10 * FLAGS.batch_size) [image, label] = provider.get(['image', 'label']) label -= FLAGS.labels_offset train_image_size = FLAGS.train_image_size or network_fn.default_image_size image = image_preprocessing_fn(image, train_image_size, train_image_size) images, labels = tf.train.batch( [image, label], batch_size=FLAGS.batch_size, num_threads=FLAGS.num_preprocessing_threads, capacity=5 * FLAGS.batch_size) labels = slim.one_hot_encoding( labels, dataset.num_classes - FLAGS.labels_offset) batch_queue = slim.prefetch_queue.prefetch_queue( [images, labels], capacity=2 * deploy_config.num_clones) #################### # Define the model # #################### def clone_fn(batch_queue): """Allows data parallelism by creating multiple clones of network_fn.""" imgs, ls = batch_queue.dequeue() logits, end_points = network_fn(imgs) ############################# # Specify the loss function # ############################# if 'AuxLogits' in end_points: slim.losses.softmax_cross_entropy( end_points['AuxLogits'], ls, label_smoothing=FLAGS.label_smoothing, weights=0.4, scope='aux_loss') slim.losses.softmax_cross_entropy( logits, ls, label_smoothing=FLAGS.label_smoothing, weights=1.0) return end_points # Gather initial summaries. summaries = set(tf.get_collection(tf.GraphKeys.SUMMARIES)) clones = model_deploy.create_clones(deploy_config, clone_fn, [batch_queue]) first_clone_scope = deploy_config.clone_scope(0) # Gather update_ops from the first clone. These contain, for example, # the updates for the batch_norm variables created by network_fn. update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS, first_clone_scope) # Add summaries for end_points. end_points = clones[0].outputs for end_point in end_points: x = end_points[end_point] summaries.add(tf.summary.histogram('activations/' + end_point, x)) summaries.add( tf.summary.scalar('sparsity/' + end_point, tf.nn.zero_fraction(x))) # Add summaries for losses. for loss in tf.get_collection(tf.GraphKeys.LOSSES, first_clone_scope): summaries.add(tf.summary.scalar('losses/%s' % loss.op.name, loss)) # Add summaries for variables. for variable in slim.get_model_variables(): summaries.add(tf.summary.histogram(variable.op.name, variable)) ################################# # Configure the moving averages # ################################# if FLAGS.moving_average_decay: moving_average_variables = slim.get_model_variables() variable_averages = tf.train.ExponentialMovingAverage( FLAGS.moving_average_decay, global_step) else: moving_average_variables, variable_averages = None, None if FLAGS.quantize_delay >= 0: tf.contrib.quantize.create_training_graph( quant_delay=FLAGS.quantize_delay) ######################################### # Configure the optimization procedure. # ######################################### with tf.device(deploy_config.optimizer_device()): learning_rate = _configure_learning_rate(dataset.num_samples, global_step) optimizer = _configure_optimizer(learning_rate) summaries.add(tf.summary.scalar('learning_rate', learning_rate)) if FLAGS.sync_replicas: # If sync_replicas is enabled, the averaging will be done in the chief # queue runner. optimizer = tf.train.SyncReplicasOptimizer( opt=optimizer, replicas_to_aggregate=FLAGS.replicas_to_aggregate, total_num_replicas=FLAGS.worker_replicas, variable_averages=variable_averages, variables_to_average=moving_average_variables) elif FLAGS.moving_average_decay: # Update ops executed locally by trainer. update_ops.append( variable_averages.apply(moving_average_variables)) # Variables to train. variables_to_train = _get_variables_to_train() # and returns a train_tensor and summary_op total_loss, clones_gradients = model_deploy.optimize_clones( clones, optimizer, var_list=variables_to_train) # Add total_loss to summary. summaries.add(tf.summary.scalar('total_loss', total_loss)) # Create gradient updates. grad_updates = optimizer.apply_gradients(clones_gradients, global_step=global_step) update_ops.append(grad_updates) update_op = tf.group(*update_ops) with tf.control_dependencies([update_op]): train_tensor = tf.identity(total_loss, name='train_op') # Add the summaries from the first clone. These contain the summaries # created by model_fn and either optimize_clones() or _gather_clone_loss(). summaries |= set( tf.get_collection(tf.GraphKeys.SUMMARIES, first_clone_scope)) # Merge all summaries together. summary_op = tf.summary.merge(list(summaries), name='summary_op') ########################### # Kicks off the training. # ########################### slim.learning.train( train_tensor, logdir=FLAGS.train_dir, master=FLAGS.master, is_chief=(FLAGS.task == 0), init_fn=_get_init_fn(), summary_op=summary_op, number_of_steps=FLAGS.max_number_of_steps, log_every_n_steps=FLAGS.log_every_n_steps, save_summaries_secs=FLAGS.save_summaries_secs, save_interval_secs=FLAGS.save_interval_secs, sync_optimizer=optimizer if FLAGS.sync_replicas else None)
def train(create_tensor_dict_fn, create_model_fn, train_config, master, task, num_clones, worker_replicas, clone_on_cpu, ps_tasks, worker_job_name, is_chief, train_dir, graph_hook_fn=None): """Training function for detection models. Args: create_tensor_dict_fn: a function to create a tensor input dictionary. create_model_fn: a function that creates a DetectionModel and generates losses. train_config: a train_pb2.TrainConfig protobuf. master: BNS name of the TensorFlow master to use. task: The task id of this training instance. num_clones: The number of clones to run per machine. worker_replicas: The number of work replicas to train with. clone_on_cpu: True if clones should be forced to run on CPU. ps_tasks: Number of parameter server tasks. worker_job_name: Name of the worker job. is_chief: Whether this replica is the chief replica. train_dir: Directory to write checkpoints and training summaries to. graph_hook_fn: Optional function that is called after the inference graph is built (before optimization). This is helpful to perform additional changes to the training graph such as adding FakeQuant ops. The function should modify the default graph. Raises: ValueError: If both num_clones > 1 and train_config.sync_replicas is true. """ detection_model = create_model_fn() data_augmentation_options = [ preprocessor_builder.build(step) for step in train_config.data_augmentation_options] with tf.Graph().as_default(): # Build a configuration specifying multi-GPU and multi-replicas. deploy_config = model_deploy.DeploymentConfig( num_clones=num_clones, clone_on_cpu=clone_on_cpu, replica_id=task, num_replicas=worker_replicas, num_ps_tasks=ps_tasks, worker_job_name=worker_job_name) # Place the global step on the device storing the variables. with tf.device(deploy_config.variables_device()): global_step = slim.create_global_step() if num_clones != 1 and train_config.sync_replicas: raise ValueError('In Synchronous SGD mode num_clones must ', 'be 1. Found num_clones: {}'.format(num_clones)) batch_size = train_config.batch_size // num_clones if train_config.sync_replicas: batch_size //= train_config.replicas_to_aggregate with tf.device(deploy_config.inputs_device()): input_queue = create_input_queue( batch_size, create_tensor_dict_fn, train_config.batch_queue_capacity, train_config.num_batch_queue_threads, train_config.prefetch_queue_capacity, data_augmentation_options) # Gather initial summaries. # TODO(rathodv): See if summaries can be added/extracted from global tf # collections so that they don't have to be passed around. summaries = set(tf.get_collection(tf.GraphKeys.SUMMARIES)) global_summaries = set([]) model_fn = functools.partial(_create_losses, create_model_fn=create_model_fn, train_config=train_config) clones = model_deploy.create_clones(deploy_config, model_fn, [input_queue]) first_clone_scope = clones[0].scope if graph_hook_fn: with tf.device(deploy_config.variables_device()): graph_hook_fn() # Gather update_ops from the first clone. These contain, for example, # the updates for the batch_norm variables created by model_fn. update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS, first_clone_scope) with tf.device(deploy_config.optimizer_device()): training_optimizer, optimizer_summary_vars = optimizer_builder.build( train_config.optimizer) for var in optimizer_summary_vars: tf.summary.scalar(var.op.name, var, family='LearningRate') sync_optimizer = None if train_config.sync_replicas: training_optimizer = tf.train.SyncReplicasOptimizer( training_optimizer, replicas_to_aggregate=train_config.replicas_to_aggregate, total_num_replicas=worker_replicas) sync_optimizer = training_optimizer with tf.device(deploy_config.optimizer_device()): regularization_losses = (None if train_config.add_regularization_loss else []) total_loss, grads_and_vars = model_deploy.optimize_clones( clones, training_optimizer, regularization_losses=regularization_losses) total_loss = tf.check_numerics(total_loss, 'LossTensor is inf or nan.') # Optionally multiply bias gradients by train_config.bias_grad_multiplier. if train_config.bias_grad_multiplier: biases_regex_list = ['.*/biases'] grads_and_vars = variables_helper.multiply_gradients_matching_regex( grads_and_vars, biases_regex_list, multiplier=train_config.bias_grad_multiplier) # Optionally freeze some layers by setting their gradients to be zero. if train_config.freeze_variables: grads_and_vars = variables_helper.freeze_gradients_matching_regex( grads_and_vars, train_config.freeze_variables) # Optionally clip gradients if train_config.gradient_clipping_by_norm > 0: with tf.name_scope('clip_grads'): grads_and_vars = slim.learning.clip_gradient_norms( grads_and_vars, train_config.gradient_clipping_by_norm) # Create gradient updates. grad_updates = training_optimizer.apply_gradients(grads_and_vars, global_step=global_step) update_ops.append(grad_updates) update_op = tf.group(*update_ops, name='update_barrier') with tf.control_dependencies([update_op]): train_tensor = tf.identity(total_loss, name='train_op') # Add summaries. for model_var in slim.get_model_variables(): global_summaries.add(tf.summary.histogram('ModelVars/' + model_var.op.name, model_var)) for loss_tensor in tf.losses.get_losses(): global_summaries.add(tf.summary.scalar('Losses/' + loss_tensor.op.name, loss_tensor)) global_summaries.add( tf.summary.scalar('Losses/TotalLoss', tf.losses.get_total_loss())) # Add the summaries from the first clone. These contain the summaries # created by model_fn and either optimize_clones() or _gather_clone_loss(). summaries |= set(tf.get_collection(tf.GraphKeys.SUMMARIES, first_clone_scope)) summaries |= global_summaries # Merge all summaries together. summary_op = tf.summary.merge(list(summaries), name='summary_op') # Soft placement allows placing on CPU ops without GPU implementation. session_config = tf.ConfigProto(allow_soft_placement=True, log_device_placement=False) # Save checkpoints regularly. keep_checkpoint_every_n_hours = train_config.keep_checkpoint_every_n_hours saver = tf.train.Saver( keep_checkpoint_every_n_hours=keep_checkpoint_every_n_hours) # Create ops required to initialize the model from a given checkpoint. init_fn = None if train_config.fine_tune_checkpoint: if not train_config.fine_tune_checkpoint_type: # train_config.from_detection_checkpoint field is deprecated. For # backward compatibility, fine_tune_checkpoint_type is set based on # from_detection_checkpoint. if train_config.from_detection_checkpoint: train_config.fine_tune_checkpoint_type = 'detection' else: train_config.fine_tune_checkpoint_type = 'classification' var_map = detection_model.restore_map( fine_tune_checkpoint_type=train_config.fine_tune_checkpoint_type, load_all_detection_checkpoint_vars=( train_config.load_all_detection_checkpoint_vars)) available_var_map = (variables_helper. get_variables_available_in_checkpoint( var_map, train_config.fine_tune_checkpoint, include_global_step=False)) init_saver = tf.train.Saver(available_var_map) def initializer_fn(sess): init_saver.restore(sess, train_config.fine_tune_checkpoint) init_fn = initializer_fn slim.learning.train( train_tensor, logdir=train_dir, master=master, is_chief=is_chief, session_config=session_config, startup_delay_steps=train_config.startup_delay_steps, init_fn=init_fn, summary_op=summary_op, number_of_steps=( train_config.num_steps if train_config.num_steps else None), save_summaries_secs=120, sync_optimizer=sync_optimizer, saver=saver)
def main(unused_argv): tf.logging.set_verbosity(tf.logging.INFO) # Set up deployment (i.e., multi-GPUs and/or multi-replicas). config = model_deploy.DeploymentConfig( num_clones=FLAGS.num_clones, clone_on_cpu=FLAGS.clone_on_cpu, replica_id=FLAGS.task, num_replicas=FLAGS.num_replicas, num_ps_tasks=FLAGS.num_ps_tasks) # Split the batch across GPUs. assert FLAGS.train_batch_size % config.num_clones == 0, ( 'Training batch size not divisble by number of clones (GPUs).') clone_batch_size = FLAGS.train_batch_size // config.num_clones # Get dataset-dependent information. dataset = segmentation_dataset.get_dataset( FLAGS.dataset, FLAGS.train_split, dataset_dir=FLAGS.dataset_dir) tf.gfile.MakeDirs(FLAGS.train_logdir) tf.logging.info('Training on %s set', FLAGS.train_split) with tf.Graph().as_default() as graph: with tf.device(config.inputs_device()): samples = input_generator.get( dataset, FLAGS.train_crop_size, clone_batch_size, min_resize_value=FLAGS.min_resize_value, max_resize_value=FLAGS.max_resize_value, resize_factor=FLAGS.resize_factor, min_scale_factor=FLAGS.min_scale_factor, max_scale_factor=FLAGS.max_scale_factor, scale_factor_step_size=FLAGS.scale_factor_step_size, dataset_split=FLAGS.train_split, is_training=True, model_variant=FLAGS.model_variant) inputs_queue = prefetch_queue.prefetch_queue( samples, capacity=128 * config.num_clones) # Create the global step on the device storing the variables. with tf.device(config.variables_device()): global_step = tf.train.get_or_create_global_step() # Define the model and create clones. model_fn = _build_deeplab model_args = (inputs_queue, { common.OUTPUT_TYPE: dataset.num_classes }, dataset.ignore_label) clones = model_deploy.create_clones(config, model_fn, args=model_args) # Gather update_ops from the first clone. These contain, for example, # the updates for the batch_norm variables created by model_fn. first_clone_scope = config.clone_scope(0) update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS, first_clone_scope) # Gather initial summaries. summaries = set(tf.get_collection(tf.GraphKeys.SUMMARIES)) # Add summaries for model variables. for model_var in slim.get_model_variables(): summaries.add(tf.summary.histogram(model_var.op.name, model_var)) # Add summaries for images, labels, semantic predictions if FLAGS.save_summaries_images: summary_image = graph.get_tensor_by_name( ('%s/%s:0' % (first_clone_scope, common.IMAGE)).strip('/')) summaries.add( tf.summary.image('samples/%s' % common.IMAGE, summary_image)) first_clone_label = graph.get_tensor_by_name( ('%s/%s:0' % (first_clone_scope, common.LABEL)).strip('/')) # Scale up summary image pixel values for better visualization. pixel_scaling = max(1, 255 // dataset.num_classes) summary_label = tf.cast(first_clone_label * pixel_scaling, tf.uint8) summaries.add( tf.summary.image('samples/%s' % common.LABEL, summary_label)) first_clone_output = graph.get_tensor_by_name( ('%s/%s:0' % (first_clone_scope, common.OUTPUT_TYPE)).strip('/')) predictions = tf.expand_dims(tf.argmax(first_clone_output, 3), -1) summary_predictions = tf.cast(predictions * pixel_scaling, tf.uint8) summaries.add( tf.summary.image( 'samples/%s' % common.OUTPUT_TYPE, summary_predictions)) # Add summaries for losses. for loss in tf.get_collection(tf.GraphKeys.LOSSES, first_clone_scope): summaries.add(tf.summary.scalar('losses/%s' % loss.op.name, loss)) # Build the optimizer based on the device specification. with tf.device(config.optimizer_device()): learning_rate = train_utils.get_model_learning_rate( FLAGS.learning_policy, FLAGS.base_learning_rate, FLAGS.learning_rate_decay_step, FLAGS.learning_rate_decay_factor, FLAGS.training_number_of_steps, FLAGS.learning_power, FLAGS.slow_start_step, FLAGS.slow_start_learning_rate) optimizer = tf.train.MomentumOptimizer(learning_rate, FLAGS.momentum) summaries.add(tf.summary.scalar('learning_rate', learning_rate)) startup_delay_steps = FLAGS.task * FLAGS.startup_delay_steps for variable in slim.get_model_variables(): summaries.add(tf.summary.histogram(variable.op.name, variable)) with tf.device(config.variables_device()): total_loss, grads_and_vars = model_deploy.optimize_clones( clones, optimizer) total_loss = tf.check_numerics(total_loss, 'Loss is inf or nan.') summaries.add(tf.summary.scalar('total_loss', total_loss)) # Modify the gradients for biases and last layer variables. last_layers = model.get_extra_layer_scopes( FLAGS.last_layers_contain_logits_only) grad_mult = train_utils.get_model_gradient_multipliers( last_layers, FLAGS.last_layer_gradient_multiplier) if grad_mult: grads_and_vars = slim.learning.multiply_gradients( grads_and_vars, grad_mult) # Create gradient update op. grad_updates = optimizer.apply_gradients( grads_and_vars, global_step=global_step) update_ops.append(grad_updates) update_op = tf.group(*update_ops) with tf.control_dependencies([update_op]): train_tensor = tf.identity(total_loss, name='train_op') # Add the summaries from the first clone. These contain the summaries # created by model_fn and either optimize_clones() or _gather_clone_loss(). summaries |= set( tf.get_collection(tf.GraphKeys.SUMMARIES, first_clone_scope)) # Merge all summaries together. summary_op = tf.summary.merge(list(summaries)) # Soft placement allows placing on CPU ops without GPU implementation. session_config = tf.ConfigProto( allow_soft_placement=True, log_device_placement=False) # Start the training. slim.learning.train( train_tensor, logdir=FLAGS.train_logdir, log_every_n_steps=FLAGS.log_steps, master=FLAGS.master, number_of_steps=FLAGS.training_number_of_steps, is_chief=(FLAGS.task == 0), session_config=session_config, startup_delay_steps=startup_delay_steps, init_fn=train_utils.get_model_init_fn( FLAGS.train_logdir, FLAGS.tf_initial_checkpoint, FLAGS.initialize_last_layer, last_layers, ignore_missing_vars=True), summary_op=summary_op, save_summaries_secs=FLAGS.save_summaries_secs, save_interval_secs=FLAGS.save_interval_secs)