# 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. import os import time from collections import deque import shutil import paddle import paddle.nn.functional as F from paddlex.paddleseg.utils import TimeAverager, calculate_eta, resume, logger from paddlex.paddleseg.core.val import evaluate def check_logits_losses(logits_list, losses): len_logits = len(logits_list) len_losses = len(losses['types']) if len_logits != len_losses: raise RuntimeError( 'The length of logits_list should equal to the types of loss config: {} != {}.' .format(len_logits, len_losses)) def loss_computation(logits_list, labels, losses, edges=None): check_logits_losses(logits_list, losses) loss_list = [] for i in range(len(logits_list)): logits = logits_list[i] loss_i = losses['types'][i] # Whether to use edges as labels According to loss type. if loss_i.__class__.__name__ in ('BCELoss', ) and loss_i.edge_label: loss_list.append(losses['coef'][i] * loss_i(logits, edges)) else: loss_list.append(losses['coef'][i] * loss_i(logits, labels)) return loss_list def train(model, train_dataset, val_dataset=None, optimizer=None, save_dir='output', iters=10000, batch_size=2, resume_model=None, save_interval=1000, log_iters=10, num_workers=0, use_vdl=False, losses=None, keep_checkpoint_max=5): """ Launch training. Args: model（nn.Layer): A sementic segmentation model. train_dataset (paddle.io.Dataset): Used to read and process training datasets. val_dataset (paddle.io.Dataset, optional): Used to read and process validation datasets. optimizer (paddle.optimizer.Optimizer): The optimizer. save_dir (str, optional): The directory for saving the model snapshot. Default: 'output'. iters (int, optional): How may iters to train the model. Defualt: 10000. batch_size (int, optional): Mini batch size of one gpu or cpu. Default: 2. resume_model (str, optional): The path of resume model. save_interval (int, optional): How many iters to save a model snapshot once during training. Default: 1000. log_iters (int, optional): Display logging information at every log_iters. Default: 10. num_workers (int, optional): Num workers for data loader. Default: 0. use_vdl (bool, optional): Whether to record the data to VisualDL during training. Default: False. losses (dict): A dict including 'types' and 'coef'. The length of coef should equal to 1 or len(losses['types']). The 'types' item is a list of object of paddleseg.models.losses while the 'coef' item is a list of the relevant coefficient. keep_checkpoint_max (int, optional): Maximum number of checkpoints to save. Default: 5. """ model.train() nranks = paddle.distributed.ParallelEnv().nranks local_rank = paddle.distributed.ParallelEnv().local_rank start_iter = 0 if resume_model is not None: start_iter = resume(model, optimizer, resume_model) if not os.path.isdir(save_dir): if os.path.exists(save_dir): os.remove(save_dir) os.makedirs(save_dir) if nranks > 1: # Initialize parallel environment if not done. if not paddle.distributed.parallel.parallel_helper._is_parallel_ctx_initialized( ): paddle.distributed.init_parallel_env() ddp_model = paddle.DataParallel(model) else: ddp_model = paddle.DataParallel(model) batch_sampler = paddle.io.DistributedBatchSampler( train_dataset, batch_size=batch_size, shuffle=True, drop_last=True) loader = paddle.io.DataLoader( train_dataset, batch_sampler=batch_sampler, num_workers=num_workers, return_list=True, ) if use_vdl: from visualdl import LogWriter log_writer = LogWriter(save_dir) avg_loss = 0.0 avg_loss_list = [] iters_per_epoch = len(batch_sampler) best_mean_iou = -1.0 best_model_iter = -1 reader_cost_averager = TimeAverager() batch_cost_averager = TimeAverager() save_models = deque() batch_start = time.time() iter = start_iter while iter < iters: for data in loader: iter += 1 if iter > iters: break reader_cost_averager.record(time.time() - batch_start) images = data[0] labels = data[1].astype('int64') edges = None if len(data) == 3: edges = data[2].astype('int64') if nranks > 1: logits_list = ddp_model(images) else: logits_list = model(images) loss_list = loss_computation( logits_list=logits_list, labels=labels, losses=losses, edges=edges) loss = sum(loss_list) loss.backward() optimizer.step() lr = optimizer.get_lr() if isinstance(optimizer._learning_rate, paddle.optimizer.lr.LRScheduler): optimizer._learning_rate.step() model.clear_gradients() avg_loss += loss.numpy()[0] if not avg_loss_list: avg_loss_list = [l.numpy() for l in loss_list] else: for i in range(len(loss_list)): avg_loss_list[i] += loss_list[i].numpy() batch_cost_averager.record( time.time() - batch_start, num_samples=batch_size) if (iter) % log_iters == 0 and local_rank == 0: avg_loss /= log_iters avg_loss_list = [l[0] / log_iters for l in avg_loss_list] remain_iters = iters - iter avg_train_batch_cost = batch_cost_averager.get_average() avg_train_reader_cost = reader_cost_averager.get_average() eta = calculate_eta(remain_iters, avg_train_batch_cost) logger.info( "[TRAIN] epoch: {}, iter: {}/{}, loss: {:.4f}, lr: {:.6f}, batch_cost: {:.4f}, reader_cost: {:.5f}, ips: {:.4f} samples/sec | ETA {}" .format((iter - 1 ) // iters_per_epoch + 1, iter, iters, avg_loss, lr, avg_train_batch_cost, avg_train_reader_cost, batch_cost_averager.get_ips_average(), eta)) if use_vdl: log_writer.add_scalar('Train/loss', avg_loss, iter) # Record all losses if there are more than 2 losses. if len(avg_loss_list) > 1: avg_loss_dict = {} for i, value in enumerate(avg_loss_list): avg_loss_dict['loss_' + str(i)] = value for key, value in avg_loss_dict.items(): log_tag = 'Train/' + key log_writer.add_scalar(log_tag, value, iter) log_writer.add_scalar('Train/lr', lr, iter) log_writer.add_scalar('Train/batch_cost', avg_train_batch_cost, iter) log_writer.add_scalar('Train/reader_cost', avg_train_reader_cost, iter) avg_loss = 0.0 avg_loss_list = [] reader_cost_averager.reset() batch_cost_averager.reset() if (iter % save_interval == 0 or iter == iters) and (val_dataset is not None): num_workers = 1 if num_workers > 0 else 0 mean_iou, acc, _, _, _ = evaluate( model, val_dataset, num_workers=num_workers) model.train() if (iter % save_interval == 0 or iter == iters) and local_rank == 0: current_save_dir = os.path.join(save_dir, "iter_{}".format(iter)) if not os.path.isdir(current_save_dir): os.makedirs(current_save_dir) paddle.save(model.state_dict(), os.path.join(current_save_dir, 'model.pdparams')) paddle.save(optimizer.state_dict(), os.path.join(current_save_dir, 'model.pdopt')) save_models.append(current_save_dir) if len(save_models) > keep_checkpoint_max > 0: model_to_remove = save_models.popleft() shutil.rmtree(model_to_remove) if val_dataset is not None: if mean_iou > best_mean_iou: best_mean_iou = mean_iou best_model_iter = iter best_model_dir = os.path.join(save_dir, "best_model") paddle.save( model.state_dict(), os.path.join(best_model_dir, 'model.pdparams')) logger.info( '[EVAL] The model with the best validation mIoU ({:.4f}) was saved at iter {}.' .format(best_mean_iou, best_model_iter)) if use_vdl: log_writer.add_scalar('Evaluate/mIoU', mean_iou, iter) log_writer.add_scalar('Evaluate/Acc', acc, iter) batch_start = time.time() # Calculate flops. if local_rank == 0: def count_syncbn(m, x, y): x = x[0] nelements = x.numel() m.total_ops += int(2 * nelements) _, c, h, w = images.shape flops = paddle.flops( model, [1, c, h, w], custom_ops={paddle.nn.SyncBatchNorm: count_syncbn}) # Sleep for half a second to let dataloader release resources. time.sleep(0.5) if use_vdl: log_writer.close()