예제 #1
0
 def test_compute(self):
     head_importance, neuron_importance = compute_neuron_head_importance(
         task_name='xnli',
         model=self.model,
         data_loader=self.data_loader,
         num_layers=3,
         num_heads=12)
     assert (len(head_importance) == 3)
     assert (len(neuron_importance) == 3)
     self.reorder_neuron_head(self.model, head_importance, neuron_importance)
예제 #2
0
def do_train(args):
    paddle.set_device("gpu" if args.n_gpu else "cpu")
    if paddle.distributed.get_world_size() > 1:
        paddle.distributed.init_parallel_env()

    set_seed(args)

    args.task_name = args.task_name.lower()
    dataset_class, metric_class = TASK_CLASSES[args.task_name]
    args.model_type = args.model_type.lower()
    model_class, tokenizer_class = MODEL_CLASSES[args.model_type]

    train_ds = dataset_class.get_datasets(['train'])

    tokenizer = tokenizer_class.from_pretrained(args.model_name_or_path)
    trans_func = partial(convert_example,
                         tokenizer=tokenizer,
                         label_list=train_ds.get_labels(),
                         max_seq_length=args.max_seq_length)
    train_ds = train_ds.apply(trans_func, lazy=True)
    train_batch_sampler = paddle.io.DistributedBatchSampler(
        train_ds, batch_size=args.batch_size, shuffle=True)
    batchify_fn = lambda samples, fn=Tuple(
        Pad(axis=0, pad_val=tokenizer.pad_token_id),  # input
        Pad(axis=0, pad_val=tokenizer.pad_token_id),  # segment
        Stack(),  # length
        Stack(dtype="int64" if train_ds.get_labels() else "float32")  # label
    ): [data for i, data in enumerate(fn(samples)) if i != 2]
    train_data_loader = DataLoader(dataset=train_ds,
                                   batch_sampler=train_batch_sampler,
                                   collate_fn=batchify_fn,
                                   num_workers=0,
                                   return_list=True)
    if args.task_name == "mnli":
        dev_dataset_matched, dev_dataset_mismatched = dataset_class.get_datasets(
            ["dev_matched", "dev_mismatched"])
        dev_dataset_matched = dev_dataset_matched.apply(trans_func, lazy=True)
        dev_dataset_mismatched = dev_dataset_mismatched.apply(trans_func,
                                                              lazy=True)
        dev_batch_sampler_matched = paddle.io.BatchSampler(
            dev_dataset_matched, batch_size=args.batch_size, shuffle=False)
        dev_data_loader_matched = DataLoader(
            dataset=dev_dataset_matched,
            batch_sampler=dev_batch_sampler_matched,
            collate_fn=batchify_fn,
            num_workers=0,
            return_list=True)
        dev_batch_sampler_mismatched = paddle.io.BatchSampler(
            dev_dataset_mismatched, batch_size=args.batch_size, shuffle=False)
        dev_data_loader_mismatched = DataLoader(
            dataset=dev_dataset_mismatched,
            batch_sampler=dev_batch_sampler_mismatched,
            collate_fn=batchify_fn,
            num_workers=0,
            return_list=True)
    else:
        dev_dataset = dataset_class.get_datasets(["dev"])
        dev_dataset = dev_dataset.apply(trans_func, lazy=True)
        dev_batch_sampler = paddle.io.BatchSampler(dev_dataset,
                                                   batch_size=args.batch_size,
                                                   shuffle=False)
        dev_data_loader = DataLoader(dataset=dev_dataset,
                                     batch_sampler=dev_batch_sampler,
                                     collate_fn=batchify_fn,
                                     num_workers=0,
                                     return_list=True)

    num_labels = 1 if train_ds.get_labels() == None else len(
        train_ds.get_labels())

    model = model_class.from_pretrained(args.model_name_or_path,
                                        num_classes=num_labels)
    if paddle.distributed.get_world_size() > 1:
        model = paddle.DataParallel(model)

    # Step1: Initialize a dictionary to save the weights from the origin BERT model.
    origin_weights = {}
    for name, param in model.named_parameters():
        origin_weights[name] = param

    # Step2: Convert origin model to supernet.
    sp_config = supernet(expand_ratio=args.width_mult_list)
    model = Convert(sp_config).convert(model)
    # Use weights saved in the dictionary to initialize supernet.
    utils.set_state_dict(model, origin_weights)
    del origin_weights

    # Step3: Define teacher model.
    teacher_model = model_class.from_pretrained(args.model_name_or_path,
                                                num_classes=num_labels)

    # Step4: Config about distillation.
    mapping_layers = ['bert.embeddings']
    for idx in range(model.bert.config['num_hidden_layers']):
        mapping_layers.append('bert.encoder.layers.{}'.format(idx))

    default_distill_config = {
        'lambda_distill': 0.1,
        'teacher_model': teacher_model,
        'mapping_layers': mapping_layers,
    }
    distill_config = DistillConfig(**default_distill_config)

    # Step5: Config in supernet training.
    ofa_model = OFA(model,
                    distill_config=distill_config,
                    elastic_order=['width'])

    criterion = paddle.nn.loss.CrossEntropyLoss() if train_ds.get_labels(
    ) else paddle.nn.loss.MSELoss()

    metric = metric_class()

    if args.task_name == "mnli":
        dev_data_loader = (dev_data_loader_matched, dev_data_loader_mismatched)

    # Step6: Calculate the importance of neurons and head,
    # and then reorder them according to the importance.
    head_importance, neuron_importance = utils.compute_neuron_head_importance(
        args.task_name,
        ofa_model.model,
        dev_data_loader,
        loss_fct=criterion,
        num_layers=model.bert.config['num_hidden_layers'],
        num_heads=model.bert.config['num_attention_heads'])
    reorder_neuron_head(ofa_model.model, head_importance, neuron_importance)

    lr_scheduler = paddle.optimizer.lr.LambdaDecay(
        args.learning_rate,
        lambda current_step, num_warmup_steps=args.warmup_steps,
        num_training_steps=args.max_steps if args.max_steps > 0 else
        (len(train_data_loader) * args.num_train_epochs): float(
            current_step) / float(max(1, num_warmup_steps))
        if current_step < num_warmup_steps else max(
            0.0,
            float(num_training_steps - current_step) / float(
                max(1, num_training_steps - num_warmup_steps))))

    optimizer = paddle.optimizer.AdamW(
        learning_rate=lr_scheduler,
        epsilon=args.adam_epsilon,
        parameters=ofa_model.model.parameters(),
        weight_decay=args.weight_decay,
        apply_decay_param_fun=lambda x: x in [
            p.name for n, p in ofa_model.model.named_parameters()
            if not any(nd in n for nd in ["bias", "norm"])
        ])

    global_step = 0
    tic_train = time.time()
    for epoch in range(args.num_train_epochs):
        # Step7: Set current epoch and task.
        ofa_model.set_epoch(epoch)
        ofa_model.set_task('width')

        for step, batch in enumerate(train_data_loader):
            global_step += 1
            input_ids, segment_ids, labels = batch

            for width_mult in args.width_mult_list:
                # Step8: Broadcast supernet config from width_mult,
                # and use this config in supernet training.
                net_config = apply_config(ofa_model, width_mult)
                ofa_model.set_net_config(net_config)
                logits, teacher_logits = ofa_model(input_ids,
                                                   segment_ids,
                                                   attention_mask=[None, None])
                rep_loss = ofa_model.calc_distill_loss()
                if args.task_name == 'sts-b':
                    logit_loss = 0.0
                else:
                    logit_loss = soft_cross_entropy(logits,
                                                    teacher_logits.detach())
                loss = rep_loss + args.lambda_logit * logit_loss
                loss.backward()
            optimizer.step()
            lr_scheduler.step()
            ofa_model.model.clear_gradients()

            if global_step % args.logging_steps == 0:
                if (not args.n_gpu > 1) or paddle.distributed.get_rank() == 0:
                    logger.info(
                        "global step %d, epoch: %d, batch: %d, loss: %f, speed: %.2f step/s"
                        % (global_step, epoch, step, loss, args.logging_steps /
                           (time.time() - tic_train)))
                tic_train = time.time()

            if global_step % args.save_steps == 0:
                if args.task_name == "mnli":
                    evaluate(teacher_model,
                             criterion,
                             metric,
                             dev_data_loader_matched,
                             width_mult=100)
                    evaluate(teacher_model,
                             criterion,
                             metric,
                             dev_data_loader_mismatched,
                             width_mult=100)
                else:
                    evaluate(teacher_model,
                             criterion,
                             metric,
                             dev_data_loader,
                             width_mult=100)
                for idx, width_mult in enumerate(args.width_mult_list):
                    net_config = apply_config(ofa_model, width_mult)
                    ofa_model.set_net_config(net_config)
                    tic_eval = time.time()
                    if args.task_name == "mnli":
                        acc = evaluate(ofa_model, criterion, metric,
                                       dev_data_loader_matched, width_mult)
                        evaluate(ofa_model, criterion, metric,
                                 dev_data_loader_mismatched, width_mult)
                        print("eval done total : %s s" %
                              (time.time() - tic_eval))
                    else:
                        acc = evaluate(ofa_model, criterion, metric,
                                       dev_data_loader, width_mult)
                        print("eval done total : %s s" %
                              (time.time() - tic_eval))

                    if (not args.n_gpu > 1
                        ) or paddle.distributed.get_rank() == 0:
                        output_dir = os.path.join(args.output_dir,
                                                  "model_%d" % global_step)
                        if not os.path.exists(output_dir):
                            os.makedirs(output_dir)
                        # need better way to get inner model of DataParallel
                        model_to_save = model._layers if isinstance(
                            model, paddle.DataParallel) else model
                        model_to_save.save_pretrained(output_dir)
                        tokenizer.save_pretrained(output_dir)