Exemplo n.º 1
0
def main():
    # See all possible arguments in src/transformers/training_args.py
    # or by passing the --help flag to this script.
    # We now keep distinct sets of args, for a cleaner separation of concerns.

    parser = HfArgumentParser(
        (ModelArguments, DataTrainingArguments, TrainingArguments))
    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
        # If we pass only one argument to the script and it's the path to a json file,
        # let's parse it to get our arguments.
        model_args, data_args, training_args = parser.parse_json_file(
            json_file=os.path.abspath(sys.argv[1]))
    else:
        model_args, data_args, training_args = parser.parse_args_into_dataclasses(
        )

    # Sending telemetry. Tracking the example usage helps us better allocate resources to maintain them. The
    # information sent is the one passed as arguments along with your Python/PyTorch versions.
    send_example_telemetry("run_t5_mlm",
                           model_args,
                           data_args,
                           framework="flax")

    if (os.path.exists(training_args.output_dir)
            and os.listdir(training_args.output_dir) and training_args.do_train
            and not training_args.overwrite_output_dir):
        raise ValueError(
            f"Output directory ({training_args.output_dir}) already exists and is not empty."
            "Use --overwrite_output_dir to overcome.")

    # Setup logging
    logging.basicConfig(
        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
        level=logging.INFO,
        datefmt="[%X]",
    )

    # Log on each process the small summary:
    logger = logging.getLogger(__name__)

    # Set the verbosity to info of the Transformers logger (on main process only):
    logger.info(f"Training/evaluation parameters {training_args}")

    # Set seed before initializing model.
    set_seed(training_args.seed)

    # Handle the repository creation
    if training_args.push_to_hub:
        if training_args.hub_model_id is None:
            repo_name = get_full_repo_name(Path(
                training_args.output_dir).absolute().name,
                                           token=training_args.hub_token)
        else:
            repo_name = training_args.hub_model_id
        repo = Repository(training_args.output_dir, clone_from=repo_name)

    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
    # (the dataset will be downloaded automatically from the datasets Hub).
    #
    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
    # 'text' is found. You can easily tweak this behavior (see below).
    if data_args.dataset_name is not None:
        # Downloading and loading a dataset from the hub.
        datasets = load_dataset(
            data_args.dataset_name,
            data_args.dataset_config_name,
            cache_dir=model_args.cache_dir,
            use_auth_token=True if model_args.use_auth_token else None,
        )

        if "validation" not in datasets.keys():
            datasets["validation"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[:{data_args.validation_split_percentage}%]",
                cache_dir=model_args.cache_dir,
                use_auth_token=True if model_args.use_auth_token else None,
            )
            datasets["train"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[{data_args.validation_split_percentage}%:]",
                cache_dir=model_args.cache_dir,
                use_auth_token=True if model_args.use_auth_token else None,
            )
    else:
        data_files = {}
        if data_args.train_file is not None:
            data_files["train"] = data_args.train_file
        if data_args.validation_file is not None:
            data_files["validation"] = data_args.validation_file
        extension = data_args.train_file.split(".")[-1]
        if extension == "txt":
            extension = "text"
        datasets = load_dataset(
            extension,
            data_files=data_files,
            cache_dir=model_args.cache_dir,
            use_auth_token=True if model_args.use_auth_token else None,
        )

        if "validation" not in datasets.keys():
            datasets["validation"] = load_dataset(
                extension,
                data_files=data_files,
                split=f"train[:{data_args.validation_split_percentage}%]",
                cache_dir=model_args.cache_dir,
                use_auth_token=True if model_args.use_auth_token else None,
            )
            datasets["train"] = load_dataset(
                extension,
                data_files=data_files,
                split=f"train[{data_args.validation_split_percentage}%:]",
                cache_dir=model_args.cache_dir,
                use_auth_token=True if model_args.use_auth_token else None,
            )
    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
    # https://huggingface.co/docs/datasets/loading_datasets.html.

    # Load pretrained model and tokenizer

    if model_args.tokenizer_name:
        tokenizer = AutoTokenizer.from_pretrained(
            model_args.tokenizer_name,
            cache_dir=model_args.cache_dir,
            use_fast=model_args.use_fast_tokenizer,
            use_auth_token=True if model_args.use_auth_token else None,
        )
    elif model_args.model_name_or_path:
        tokenizer = AutoTokenizer.from_pretrained(
            model_args.model_name_or_path,
            cache_dir=model_args.cache_dir,
            use_fast=model_args.use_fast_tokenizer,
            use_auth_token=True if model_args.use_auth_token else None,
        )
    else:
        raise ValueError(
            "You are instantiating a new tokenizer from scratch. This is not supported by this script."
            "You can do it from another script, save it, and load it from here, using --tokenizer_name."
        )

    if model_args.config_name:
        config = T5Config.from_pretrained(
            model_args.config_name,
            cache_dir=model_args.cache_dir,
            vocab_size=len(tokenizer),
            use_auth_token=True if model_args.use_auth_token else None,
        )
    elif model_args.model_name_or_path:
        config = T5Config.from_pretrained(
            model_args.model_name_or_path,
            cache_dir=model_args.cache_dir,
            use_auth_token=True if model_args.use_auth_token else None,
        )
    else:
        config = CONFIG_MAPPING[model_args.model_type]()
        logger.warning(
            "You are instantiating a new config instance from scratch.")

    # Preprocessing the datasets.
    # First we tokenize all the texts.
    if training_args.do_train:
        column_names = datasets["train"].column_names
    else:
        column_names = datasets["validation"].column_names
    text_column_name = "text" if "text" in column_names else column_names[0]

    max_seq_length = min(data_args.max_seq_length, tokenizer.model_max_length)

    # Otherwise, we tokenize every text, then concatenate them together before splitting them in smaller parts.
    # Since we make sure that all sequences are of the same length, no attention_mask is needed.
    def tokenize_function(examples):
        return tokenizer(examples[text_column_name],
                         return_attention_mask=False)

    tokenized_datasets = datasets.map(
        tokenize_function,
        batched=True,
        num_proc=data_args.preprocessing_num_workers,
        remove_columns=column_names,
        load_from_cache_file=not data_args.overwrite_cache,
    )

    # T5-like span masked language modeling will fuse consecutively masked tokens to a single sentinel token.
    # To ensure that the input length is `max_seq_length`, we need to increase the maximum length
    # according to `mlm_probability` and `mean_noise_span_length`. We can also define the label length accordingly.
    expanded_inputs_length, targets_length = compute_input_and_target_lengths(
        inputs_length=max_seq_length,
        noise_density=data_args.mlm_probability,
        mean_noise_span_length=data_args.mean_noise_span_length,
    )

    # Main data processing function that will concatenate all texts from our dataset and generate chunks of expanded_inputs_length.
    def group_texts(examples):
        # Concatenate all texts.
        concatenated_examples = {
            k: list(chain(*examples[k]))
            for k in examples.keys()
        }
        total_length = len(concatenated_examples[list(examples.keys())[0]])
        # We drop the small remainder, we could add padding if the model supported it instead of this drop, you can
        # customize this part to your needs.
        if total_length >= expanded_inputs_length:
            total_length = (total_length //
                            expanded_inputs_length) * expanded_inputs_length
        # Split by chunks of max_len.
        result = {
            k: [
                t[i:i + expanded_inputs_length]
                for i in range(0, total_length, expanded_inputs_length)
            ]
            for k, t in concatenated_examples.items()
        }
        return result

    # Note that with `batched=True`, this map processes 1,000 texts together, so group_texts throws away a
    # remainder for each of those groups of 1,000 texts. You can adjust that batch_size here but a higher value
    # might be slower to preprocess.
    #
    # To speed up this part, we use multiprocessing. See the documentation of the map method for more information:
    # https://huggingface.co/docs/datasets/package_reference/main_classes.html#datasets.Dataset.map
    tokenized_datasets = tokenized_datasets.map(
        group_texts,
        batched=True,
        num_proc=data_args.preprocessing_num_workers,
        load_from_cache_file=not data_args.overwrite_cache,
    )

    # Enable tensorboard only on the master node
    has_tensorboard = is_tensorboard_available()
    if has_tensorboard and jax.process_index() == 0:
        try:
            from flax.metrics.tensorboard import SummaryWriter

            summary_writer = SummaryWriter(
                log_dir=Path(training_args.output_dir))
        except ImportError as ie:
            has_tensorboard = False
            logger.warning(
                f"Unable to display metrics through TensorBoard because some package are not installed: {ie}"
            )
    else:
        logger.warning(
            "Unable to display metrics through TensorBoard because the package is not installed: "
            "Please run pip install tensorboard to enable.")

    # Initialize our training
    rng = jax.random.PRNGKey(training_args.seed)
    dropout_rngs = jax.random.split(rng, jax.local_device_count())

    if model_args.model_name_or_path:
        model = FlaxT5ForConditionalGeneration.from_pretrained(
            model_args.model_name_or_path,
            config=config,
            seed=training_args.seed,
            dtype=getattr(jnp, model_args.dtype),
            use_auth_token=True if model_args.use_auth_token else None,
        )
    else:
        config.vocab_size = len(tokenizer)
        model = FlaxT5ForConditionalGeneration(
            config,
            seed=training_args.seed,
            dtype=getattr(jnp, model_args.dtype),
        )

    # Data collator
    # This one will take care of randomly masking the tokens.
    data_collator = FlaxDataCollatorForT5MLM(
        tokenizer=tokenizer,
        noise_density=data_args.mlm_probability,
        mean_noise_span_length=data_args.mean_noise_span_length,
        input_length=max_seq_length,
        target_length=targets_length,
        pad_token_id=model.config.pad_token_id,
        decoder_start_token_id=model.config.decoder_start_token_id,
    )

    # Store some constant
    num_epochs = int(training_args.num_train_epochs)
    train_batch_size = int(
        training_args.per_device_train_batch_size) * jax.device_count()
    per_device_eval_batch_size = int(training_args.per_device_eval_batch_size)
    eval_batch_size = per_device_eval_batch_size * jax.device_count()

    num_train_steps = len(
        tokenized_datasets["train"]) // train_batch_size * num_epochs

    num_of_hosts = jax.process_count()
    current_host_idx = jax.process_index()

    # Create learning rate schedule
    warmup_fn = optax.linear_schedule(
        init_value=0.0,
        end_value=training_args.learning_rate,
        transition_steps=training_args.warmup_steps)
    decay_fn = optax.linear_schedule(
        init_value=training_args.learning_rate,
        end_value=0,
        transition_steps=num_train_steps - training_args.warmup_steps,
    )
    linear_decay_lr_schedule_fn = optax.join_schedules(
        schedules=[warmup_fn, decay_fn],
        boundaries=[training_args.warmup_steps])

    # We use Optax's "masking" functionality to not apply weight decay
    # to bias and LayerNorm scale parameters. decay_mask_fn returns a
    # mask boolean with the same structure as the parameters.
    # The mask is True for parameters that should be decayed.
    def decay_mask_fn(params):
        flat_params = traverse_util.flatten_dict(params)
        # find out all LayerNorm parameters
        layer_norm_candidates = ["layernorm", "layer_norm", "ln"]
        layer_norm_named_params = set([
            layer[-2:] for layer_norm_name in layer_norm_candidates
            for layer in flat_params.keys()
            if layer_norm_name in "".join(layer).lower()
        ])
        flat_mask = {
            path: (path[-1] != "bias"
                   and path[-2:] not in layer_norm_named_params)
            for path in flat_params
        }
        return traverse_util.unflatten_dict(flat_mask)

    # create adam optimizer
    if training_args.adafactor:
        # We use the default parameters here to initialize adafactor,
        # For more details about the parameters please check https://github.com/deepmind/optax/blob/ed02befef9bf81cbbf236be3d2b0e032e9ed4a40/optax/_src/alias.py#L74
        optimizer = optax.adafactor(
            learning_rate=linear_decay_lr_schedule_fn, )
    else:
        optimizer = optax.adamw(
            learning_rate=linear_decay_lr_schedule_fn,
            b1=training_args.adam_beta1,
            b2=training_args.adam_beta2,
            weight_decay=training_args.weight_decay,
            mask=decay_mask_fn,
        )

    # Setup train state
    state = train_state.TrainState.create(apply_fn=model.__call__,
                                          params=model.params,
                                          tx=optimizer)

    # Define gradient update step fn
    def train_step(state, batch, dropout_rng):
        dropout_rng, new_dropout_rng = jax.random.split(dropout_rng)

        def loss_fn(params):
            labels = batch.pop("labels")

            logits = state.apply_fn(**batch,
                                    params=params,
                                    dropout_rng=dropout_rng,
                                    train=True)[0]

            # compute loss
            loss = optax.softmax_cross_entropy(
                logits, onehot(labels, logits.shape[-1])).mean()

            return loss

        grad_fn = jax.value_and_grad(loss_fn)
        loss, grad = grad_fn(state.params)
        grad = jax.lax.pmean(grad, "batch")
        new_state = state.apply_gradients(grads=grad)

        metrics = jax.lax.pmean(
            {
                "loss": loss,
                "learning_rate": linear_decay_lr_schedule_fn(state.step)
            },
            axis_name="batch")

        return new_state, metrics, new_dropout_rng

    # Create parallel version of the train step
    p_train_step = jax.pmap(train_step, "batch", donate_argnums=(0, ))

    # Define eval fn
    def eval_step(params, batch):
        labels = batch.pop("labels")

        logits = model(**batch, params=params, train=False)[0]

        # compute loss
        loss = optax.softmax_cross_entropy(logits,
                                           onehot(labels, logits.shape[-1]))

        # compute accuracy
        accuracy = jnp.equal(jnp.argmax(logits, axis=-1), labels)

        # summarize metrics
        metrics = {"loss": loss.mean(), "accuracy": accuracy.mean()}
        metrics = jax.lax.pmean(metrics, axis_name="batch")

        return metrics

    p_eval_step = jax.pmap(eval_step, "batch", donate_argnums=(0, ))

    # Replicate the train state on each device
    state = jax_utils.replicate(state)

    train_time = 0
    epochs = tqdm(range(num_epochs), desc="Epoch ... ", position=0)
    for epoch in epochs:
        # ======================== Training ================================
        train_start = time.time()
        train_metrics = []

        # Create sampling rng
        rng, input_rng = jax.random.split(rng)

        # Generate an epoch by shuffling sampling indices from the train dataset
        num_train_samples = len(tokenized_datasets["train"])
        # Avoid using jax.numpy here in case of TPU training
        train_samples_idx = np.random.permutation(np.arange(num_train_samples))
        train_batch_idx = generate_batch_splits(train_samples_idx,
                                                train_batch_size)

        # Gather the indexes for creating the batch and do a training step
        for step, batch_idx in enumerate(
                tqdm(train_batch_idx, desc="Training...", position=1)):
            samples = [
                tokenized_datasets["train"][int(idx)] for idx in batch_idx
            ]
            model_inputs = data_collator(samples)

            local_host_model_inputs = {
                key: np.split(model_inputs.data[key], num_of_hosts,
                              axis=0)[current_host_idx]
                for key, value in model_inputs.data.items()
            }

            # Model forward
            model_inputs = shard(local_host_model_inputs)
            state, train_metric, dropout_rngs = p_train_step(
                state, model_inputs, dropout_rngs)
            train_metrics.append(train_metric)

            cur_step = epoch * (num_train_samples // train_batch_size) + step

            if cur_step % training_args.logging_steps == 0 and cur_step > 0:
                # Save metrics
                train_metric = jax_utils.unreplicate(train_metric)
                train_time += time.time() - train_start
                if has_tensorboard and jax.process_index() == 0:
                    write_train_metric(summary_writer, train_metrics,
                                       train_time, cur_step)

                epochs.write(
                    f"Step... ({cur_step} | Loss: {train_metric['loss'].mean()}, Learning Rate:"
                    f" {train_metric['learning_rate'].mean()})")

                train_metrics = []

            if cur_step % training_args.eval_steps == 0 and cur_step > 0:
                # ======================== Evaluating ==============================
                num_eval_samples = len(tokenized_datasets["validation"])
                # Avoid using jax.numpy here in case of TPU training
                eval_samples_idx = np.arange(num_eval_samples)
                eval_batch_idx = generate_batch_splits(eval_samples_idx,
                                                       eval_batch_size,
                                                       drop_last=False)

                eval_metrics = []
                for i, batch_idx in enumerate(
                        tqdm(eval_batch_idx, desc="Evaluating ...",
                             position=2)):
                    samples = [
                        tokenized_datasets["validation"][int(idx)]
                        for idx in batch_idx
                    ]
                    model_inputs = data_collator(samples)

                    # Model forward
                    metrics = pad_shard_unpad(p_eval_step, static_return=True)(
                        state.params,
                        model_inputs.data,
                        min_device_batch=per_device_eval_batch_size)
                    eval_metrics.append(metrics)

                # get eval metrics
                eval_metrics = get_metrics(eval_metrics)
                eval_metrics = jax.tree_map(jnp.mean, eval_metrics)

                # Update progress bar
                epochs.write(
                    f"Step... ({cur_step} | Loss: {eval_metrics['loss']}, Acc: {eval_metrics['accuracy']})"
                )

                # Save metrics
                if has_tensorboard and jax.process_index() == 0:
                    write_eval_metric(summary_writer, eval_metrics, cur_step)

            if cur_step % training_args.save_steps == 0 and cur_step > 0:
                # save checkpoint after each epoch and push checkpoint to the hub
                if jax.process_index() == 0:
                    params = jax.device_get(
                        jax.tree_map(lambda x: x[0], state.params))
                    model.save_pretrained(training_args.output_dir,
                                          params=params)
                    tokenizer.save_pretrained(training_args.output_dir)
                    if training_args.push_to_hub:
                        repo.push_to_hub(
                            commit_message=
                            f"Saving weights and logs of step {cur_step}",
                            blocking=False)

    # Eval after training
    if training_args.do_eval:
        num_eval_samples = len(tokenized_datasets["validation"])
        # Avoid using jax.numpy here in case of TPU training
        eval_samples_idx = np.arange(num_eval_samples)
        eval_batch_idx = generate_batch_splits(eval_samples_idx,
                                               eval_batch_size,
                                               drop_last=False)

        eval_metrics = []
        for i, batch_idx in enumerate(
                tqdm(eval_batch_idx, desc="Evaluating ...", position=2)):
            samples = [
                tokenized_datasets["validation"][int(idx)] for idx in batch_idx
            ]
            model_inputs = data_collator(samples)

            # Model forward
            metrics = pad_shard_unpad(p_eval_step, static_return=True)(
                state.params,
                model_inputs.data,
                min_device_batch=per_device_eval_batch_size)
            eval_metrics.append(metrics)

        # get eval metrics
        eval_metrics = get_metrics(eval_metrics)
        eval_metrics = jax.tree_map(lambda metric: jnp.mean(metric).item(),
                                    eval_metrics)

        if jax.process_index() == 0:
            eval_metrics = {
                f"eval_{metric_name}": value
                for metric_name, value in eval_metrics.items()
            }
            path = os.path.join(training_args.output_dir, "eval_results.json")
            with open(path, "w") as f:
                json.dump(eval_metrics, f, indent=4, sort_keys=True)
Exemplo n.º 2
0
def main():
    # See all possible arguments in src/transformers/training_args.py
    # or by passing the --help flag to this script.
    # We now keep distinct sets of args, for a cleaner separation of concerns.

    parser = HfArgumentParser(
        (ModelArguments, DataTrainingArguments, TrainingArguments))
    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
        # If we pass only one argument to the script and it's the path to a json file,
        # let's parse it to get our arguments.
        model_args, data_args, training_args = parser.parse_json_file(
            json_file=os.path.abspath(sys.argv[1]))
    else:
        model_args, data_args, training_args = parser.parse_args_into_dataclasses(
        )

    if (os.path.exists(training_args.output_dir)
            and os.listdir(training_args.output_dir) and training_args.do_train
            and not training_args.overwrite_output_dir):
        raise ValueError(
            f"Output directory ({training_args.output_dir}) already exists and is not empty."
            "Use --overwrite_output_dir to overcome.")

    # Make one log on every process with the configuration for debugging.
    logging.basicConfig(
        format="%(asctime)s - %(levelname)s - %(name)s - %(message)s",
        datefmt="%m/%d/%Y %H:%M:%S",
        level=logging.INFO,
    )
    # Setup logging, we only want one process per machine to log things on the screen.
    logger.setLevel(logging.INFO if jax.process_index() ==
                    0 else logging.ERROR)
    if jax.process_index() == 0:
        datasets.utils.logging.set_verbosity_warning()
        transformers.utils.logging.set_verbosity_info()
    else:
        datasets.utils.logging.set_verbosity_error()
        transformers.utils.logging.set_verbosity_error()

    # Set the verbosity to info of the Transformers logger (on main process only):
    logger.info(f"Training/evaluation parameters {training_args}")

    # Set seed before initializing model.
    set_seed(training_args.seed)

    #  Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
    # (the dataset will be downloaded automatically from the datasets Hub).
    #
    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
    # 'text' is found. You can easily tweak this behavior (see below).
    #
    # In distributed training, the load_dataset function guarantees that only one local process can concurrently
    # download the dataset.
    if data_args.dataset_name is not None:
        # Downloading and loading a dataset from the hub.
        dataset = load_dataset(data_args.dataset_name,
                               data_args.dataset_config_name,
                               cache_dir=model_args.cache_dir,
                               keep_in_memory=False)

        if "validation" not in dataset.keys():
            dataset["validation"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[:{data_args.validation_split_percentage}%]",
                cache_dir=model_args.cache_dir,
            )
            dataset["train"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[{data_args.validation_split_percentage}%:]",
                cache_dir=model_args.cache_dir,
            )
    else:
        data_files = {}
        if data_args.train_file is not None:
            data_files["train"] = data_args.train_file
        if data_args.validation_file is not None:
            data_files["validation"] = data_args.validation_file
        extension = data_args.train_file.split(".")[-1]
        if extension == "txt":
            extension = "text"
        dataset = load_dataset(extension,
                               data_files=data_files,
                               cache_dir=model_args.cache_dir)

        if "validation" not in dataset.keys():
            dataset["validation"] = load_dataset(
                extension,
                data_files=data_files,
                split=f"train[:{data_args.validation_split_percentage}%]",
                cache_dir=model_args.cache_dir,
            )
            dataset["train"] = load_dataset(
                extension,
                data_files=data_files,
                split=f"train[{data_args.validation_split_percentage}%:]",
                cache_dir=model_args.cache_dir,
            )
    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
    # https://huggingface.co/docs/datasets/loading_datasets.html.

    # Load pretrained model and tokenizer

    # Distributed training:
    # The .from_pretrained methods guarantee that only one local process can concurrently
    # download model & vocab.
    if model_args.config_name:
        config = AutoConfig.from_pretrained(model_args.config_name,
                                            cache_dir=model_args.cache_dir)
    elif model_args.model_name_or_path:
        config = AutoConfig.from_pretrained(model_args.model_name_or_path,
                                            cache_dir=model_args.cache_dir)
    else:
        config = CONFIG_MAPPING[model_args.model_type]()
        logger.warning(
            "You are instantiating a new config instance from scratch.")

    if model_args.tokenizer_name:
        tokenizer = AutoTokenizer.from_pretrained(
            model_args.tokenizer_name,
            cache_dir=model_args.cache_dir,
            use_fast=model_args.use_fast_tokenizer)
    elif model_args.model_name_or_path:
        tokenizer = AutoTokenizer.from_pretrained(
            model_args.model_name_or_path,
            cache_dir=model_args.cache_dir,
            use_fast=model_args.use_fast_tokenizer)
    else:
        raise ValueError(
            "You are instantiating a new tokenizer from scratch. This is not supported by this script."
            "You can do it from another script, save it, and load it from here, using --tokenizer_name."
        )

    if model_args.model_name_or_path:
        model = FlaxAutoModelForCausalLM.from_pretrained(
            model_args.model_name_or_path,
            config=config,
            seed=training_args.seed,
            dtype=getattr(jnp, model_args.dtype))
    else:
        model = FlaxAutoModelForCausalLM.from_config(config,
                                                     seed=training_args.seed,
                                                     dtype=getattr(
                                                         jnp,
                                                         model_args.dtype))

    # Preprocessing the datasets.
    # First we tokenize all the texts.
    if training_args.do_train:
        column_names = dataset["train"].column_names
    else:
        column_names = dataset["validation"].column_names
    text_column_name = "text" if "text" in column_names else column_names[0]

    # since this will be pickled to avoid _LazyModule error in Hasher force logger loading before tokenize_function
    tok_logger = transformers.utils.logging.get_logger(
        "transformers.tokenization_utils_base")

    def tokenize_function(examples):
        with CaptureLogger(tok_logger) as cl:
            output = tokenizer(examples[text_column_name])
        # clm input could be much much longer than block_size
        if "Token indices sequence length is longer than the" in cl.out:
            tok_logger.warning(
                "^^^^^^^^^^^^^^^^ Please ignore the warning above - this long input will be chunked into smaller bits before being passed to the model."
            )
        return output

    tokenized_datasets = dataset.map(
        tokenize_function,
        batched=True,
        num_proc=data_args.preprocessing_num_workers,
        remove_columns=column_names,
        load_from_cache_file=not data_args.overwrite_cache,
    )

    if data_args.block_size is None:
        block_size = tokenizer.model_max_length
        if block_size > config.max_position_embeddings:
            logger.warning(
                f"The tokenizer picked seems to have a very large `model_max_length` ({tokenizer.model_max_length}). "
                "Picking 1024 instead. You can change that default value by passing --block_size xxx."
            )
            block_size = 1024
    else:
        if data_args.block_size > tokenizer.model_max_length:
            logger.warning(
                f"The block_size passed ({data_args.block_size}) is larger than the maximum length for the model"
                f"({tokenizer.model_max_length}). Using block_size={tokenizer.model_max_length}."
            )
        block_size = min(data_args.block_size, tokenizer.model_max_length)

    # Main data processing function that will concatenate all texts from our dataset and generate chunks of block_size.
    def group_texts(examples):
        # Concatenate all texts.
        concatenated_examples = {
            k: sum(examples[k], [])
            for k in examples.keys()
        }
        total_length = len(concatenated_examples[list(examples.keys())[0]])
        # We drop the small remainder, we could add padding if the model supported it instead of this drop, you can
        # customize this part to your needs.
        if total_length >= block_size:
            total_length = (total_length // block_size) * block_size
        # Split by chunks of max_len.
        result = {
            k:
            [t[i:i + block_size] for i in range(0, total_length, block_size)]
            for k, t in concatenated_examples.items()
        }
        result["labels"] = result["input_ids"].copy()
        return result

    # Note that with `batched=True`, this map processes 1,000 texts together, so group_texts throws away a remainder
    # for each of those groups of 1,000 texts. You can adjust that batch_size here but a higher value might be slower
    # to preprocess.
    #
    # To speed up this part, we use multiprocessing. See the documentation of the map method for more information:
    # https://huggingface.co/docs/datasets/package_reference/main_classes.html#datasets.Dataset.map

    lm_datasets = tokenized_datasets.map(
        group_texts,
        batched=True,
        num_proc=data_args.preprocessing_num_workers,
        load_from_cache_file=not data_args.overwrite_cache,
    )

    if training_args.do_train:
        if "train" not in tokenized_datasets:
            raise ValueError("--do_train requires a train dataset")
        train_dataset = lm_datasets["train"]
        if data_args.max_train_samples is not None:
            train_dataset = train_dataset.select(
                range(data_args.max_train_samples))

    if training_args.do_eval:
        if "validation" not in tokenized_datasets:
            raise ValueError("--do_eval requires a validation dataset")
        eval_dataset = lm_datasets["validation"]
        if data_args.max_eval_samples is not None:
            eval_dataset = eval_dataset.select(
                range(data_args.max_eval_samples))

    # Enable tensorboard only on the master node
    has_tensorboard = is_tensorboard_available()
    if has_tensorboard and jax.process_index() == 0:
        try:
            from flax.metrics.tensorboard import SummaryWriter

            summary_writer = SummaryWriter(
                log_dir=Path(training_args.output_dir))
        except ImportError as ie:
            has_tensorboard = False
            logger.warning(
                f"Unable to display metrics through TensorBoard because some package are not installed: {ie}"
            )
    else:
        logger.warning(
            "Unable to display metrics through TensorBoard because the package is not installed: "
            "Please run pip install tensorboard to enable.")

    # Initialize our training
    rng = jax.random.PRNGKey(training_args.seed)
    rng, dropout_rng = jax.random.split(rng)

    # Store some constant
    num_epochs = int(training_args.num_train_epochs)
    train_batch_size = int(
        training_args.per_device_train_batch_size) * jax.device_count()
    eval_batch_size = int(
        training_args.per_device_eval_batch_size) * jax.device_count()
    steps_per_epoch = len(train_dataset) // train_batch_size
    total_train_steps = steps_per_epoch * num_epochs

    # Create learning rate schedule
    linear_decay_lr_schedule_fn = create_learning_rate_fn(
        len(train_dataset),
        train_batch_size,
        training_args.num_train_epochs,
        training_args.warmup_steps,
        training_args.learning_rate,
    )

    # We use Optax's "masking" functionality to not apply weight decay
    # to bias and LayerNorm scale parameters. decay_mask_fn returns a
    # mask boolean with the same structure as the parameters.
    # The mask is True for parameters that should be decayed.
    # Note that this mask is specifically adapted for FlaxGPT2.
    # For other models, one should correct the layer norm parameter naming
    # accordingly.
    def decay_mask_fn(params):
        flat_params = traverse_util.flatten_dict(params)
        flat_mask = {
            path: (path[-1] != "bias" and path[-2:] not in [("ln_1", "scale"),
                                                            ("ln_2", "scale"),
                                                            ("ln_f", "scale")])
            for path in flat_params
        }
        return traverse_util.unflatten_dict(flat_mask)

    # create adam optimizer
    if training_args.adafactor:
        # We use the default parameters here to initialize adafactor,
        # For more details about the parameters please check https://github.com/deepmind/optax/blob/ed02befef9bf81cbbf236be3d2b0e032e9ed4a40/optax/_src/alias.py#L74
        optimizer = optax.adafactor(
            learning_rate=linear_decay_lr_schedule_fn, )
    else:
        optimizer = optax.adamw(
            learning_rate=linear_decay_lr_schedule_fn,
            b1=training_args.adam_beta1,
            b2=training_args.adam_beta2,
            eps=training_args.adam_epsilon,
            weight_decay=training_args.weight_decay,
            mask=decay_mask_fn,
        )

    # Setup train state
    state = TrainState.create(apply_fn=model.__call__,
                              params=model.params,
                              tx=optimizer,
                              dropout_rng=dropout_rng)

    def loss_fn(logits, labels):
        shift_logits = logits[..., :-1, :]
        shift_labels = labels[..., 1:]
        loss = optax.softmax_cross_entropy(
            shift_logits, onehot(shift_labels, shift_logits.shape[-1]))
        return loss.mean()

    # Define gradient update step fn
    def train_step(state, batch):
        dropout_rng, new_dropout_rng = jax.random.split(state.dropout_rng)

        def compute_loss(params):
            labels = batch.pop("labels")
            logits = state.apply_fn(**batch,
                                    params=params,
                                    dropout_rng=dropout_rng,
                                    train=True)[0]
            loss = loss_fn(logits, labels)
            return loss

        grad_fn = jax.value_and_grad(compute_loss)
        loss, grad = grad_fn(state.params)
        grad = jax.lax.pmean(grad, "batch")

        new_state = state.apply_gradients(grads=grad,
                                          dropout_rng=new_dropout_rng)

        metrics = {
            "loss": loss,
            "learning_rate": linear_decay_lr_schedule_fn(state.step)
        }
        metrics = jax.lax.pmean(metrics, axis_name="batch")

        return new_state, metrics

    # Define eval fn
    def eval_step(params, batch):
        labels = batch.pop("labels")
        logits = model(**batch, params=params, train=False)[0]
        loss = loss_fn(logits, labels)

        # summarize metrics
        metrics = {"loss": loss}
        metrics = jax.lax.pmean(metrics, axis_name="batch")
        return metrics

    # Create parallel version of the train and eval step
    p_train_step = jax.pmap(train_step, "batch", donate_argnums=(0, ))
    p_eval_step = jax.pmap(eval_step, "batch")

    # Replicate the train state on each device
    state = state.replicate()

    logger.info("***** Running training *****")
    logger.info(f"  Num examples = {len(train_dataset)}")
    logger.info(f"  Num Epochs = {num_epochs}")
    logger.info(
        f"  Instantaneous batch size per device = {training_args.per_device_train_batch_size}"
    )
    logger.info(
        f"  Total train batch size (w. parallel & distributed) = {train_batch_size}"
    )
    logger.info(f"  Total optimization steps = {total_train_steps}")

    train_time = 0
    train_metrics = []
    epochs = tqdm(range(num_epochs), desc="Epoch ... ", position=0)
    for epoch in epochs:
        # ======================== Training ================================
        train_start = time.time()

        # Create sampling rng
        rng, input_rng = jax.random.split(rng)

        # Generate an epoch by shuffling sampling indices from the train dataset
        train_loader = data_loader(input_rng,
                                   train_dataset,
                                   train_batch_size,
                                   shuffle=True)
        steps_per_epoch = len(train_dataset) // train_batch_size
        # train
        for step in tqdm(range(steps_per_epoch),
                         desc="Training...",
                         position=1,
                         leave=False):
            batch = next(train_loader)
            batch = shard(batch)
            state, train_metric = p_train_step(state, batch)
            train_metrics.append(train_metric)

            cur_step = epoch * (len(train_dataset) // train_batch_size) + step

            if cur_step % training_args.logging_steps == 0 and cur_step > 0:
                # Save metrics
                train_metric = unreplicate(train_metric)
                train_time += time.time() - train_start
                if has_tensorboard and jax.process_index() == 0:
                    write_train_metric(summary_writer, train_metrics,
                                       train_time, cur_step)

                epochs.write(
                    f"Step... ({cur_step} | Loss: {train_metric['loss'].mean()}, Learning Rate: {train_metric['learning_rate'].mean()})"
                )

                train_metrics = []

            if cur_step % training_args.eval_steps == 0 and cur_step > 0:
                # ======================== Evaluating ==============================
                eval_metrics = []
                eval_loader = data_loader(input_rng, eval_dataset,
                                          eval_batch_size)
                eval_steps = len(eval_dataset) // eval_batch_size
                for _ in tqdm(range(eval_steps),
                              desc="Evaluating...",
                              position=2,
                              leave=False):
                    # Model forward
                    batch = next(eval_loader)
                    batch = shard(batch)
                    metrics = p_eval_step(state.params, batch)
                    eval_metrics.append(metrics)

                # normalize eval metrics
                eval_metrics = get_metrics(eval_metrics)
                eval_metrics = jax.tree_map(jnp.mean, eval_metrics)

                try:
                    eval_metrics["perplexity"] = math.exp(eval_metrics["loss"])
                except OverflowError:
                    eval_metrics["perplexity"] = float("inf")

                # Print metrics and update progress bar
                desc = f"Step... ({cur_step} | Eval Loss: {eval_metrics['loss']} | Eval Perplexity: {eval_metrics['perplexity']})"
                epochs.write(desc)
                epochs.desc = desc

                # Save metrics
                if has_tensorboard and jax.process_index() == 0:
                    write_eval_metric(summary_writer, eval_metrics, cur_step)

            if cur_step % training_args.save_steps == 0 and cur_step > 0:
                # save checkpoint after each epoch and push checkpoint to the hub
                if jax.process_index() == 0:
                    params = jax.device_get(unreplicate(state.params))
                    model.save_pretrained(
                        training_args.output_dir,
                        params=params,
                        push_to_hub=training_args.push_to_hub,
                        commit_message=
                        f"Saving weights and logs of step {cur_step}",
                    )
Exemplo n.º 3
0
    # mask boolean with the same structure as the parameters.
    # The mask is True for parameters that should be decayed.
    # Note that this mask is specifically adapted for FlaxBERT-like models.
    # For other models, one should correct the layer norm parameter naming
    # accordingly.
    def decay_mask_fn(params):
        flat_params = traverse_util.flatten_dict(params)
        flat_mask = {path: (path[-1] != "bias" and path[-2:] != ("LayerNorm", "scale")) for path in flat_params}
        return traverse_util.unflatten_dict(flat_mask)

    # create adam optimizer
    if training_args.adafactor:
        # We use the default parameters here to initialize adafactor,
        # For more details about the parameters please check https://github.com/deepmind/optax/blob/ed02befef9bf81cbbf236be3d2b0e032e9ed4a40/optax/_src/alias.py#L74
        optimizer = optax.adafactor(
            learning_rate=linear_decay_lr_schedule_fn,
        )
    else:
        optimizer = optax.adamw(
            learning_rate=linear_decay_lr_schedule_fn,
            b1=training_args.adam_beta1,
            b2=training_args.adam_beta2,
            eps=training_args.adam_epsilon,
            weight_decay=training_args.weight_decay,
            mask=decay_mask_fn,
        )

    # Setup train state
    state = train_state.TrainState.create(apply_fn=model.__call__, params=model.params, tx=optimizer)

    # Define gradient update step fn
Exemplo n.º 4
0
 def update(
         self, gradient: Weights, state: GenericGradientState,
         parameters: Optional[Weights]
 ) -> Tuple[Weights, GenericGradientState]:
     return GenericGradientState.wrap(*adafactor(
         **asdict(self)).update(gradient, state.data, parameters))
Exemplo n.º 5
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 def init(self, parameters: Weights) -> GenericGradientState:
     return GenericGradientState(adafactor(**asdict(self)).init(parameters))
Exemplo n.º 6
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def vb_gauss_lowrank(key,
                     logjoint_fn,
                     data,
                     nfeatures,
                     initial_mean=None,
                     initial_std=0.1,
                     initial_scale=1.,
                     nsamples=20,
                     niters=200,
                     optimizer=optax.adafactor(1e-3),
                     threshold=2500,
                     window_size=None):
    '''
    Parameters
    ----------
    key : jax.random.PRNGKey

    logjoint_fn : Callable
        Log joint function

    data : Tuple
        The data to which the model is fitted, specified as a table or matrix.

    nfeatures :
        Number of features

    initial_mean :

    initial_std :
        Standard deviation of normal distribution for initialization

    initial_scale : float
        The constant factor  to scale the initial values.

    num_samples : int
        Monte Carlo samples to estimate the lower bound

    niters : int
        Maximum number of iterations

    optimizer : optax.optimizers

    threshold : float
        Gradient clipping threshold

    window_size : int
        Rolling window size to smooth the lower bound.
        Default value of window size is None,  which indicates that lower bounds won't be smoothed.

    Returns
    -------
    Tuple: Consists of
            1. mu : Estimation of variational mean
            2. b : The vector factor loading vector component of the variational covariance matrix
            3. c : The diagonal matrix component of the variational covariance matrix

    Array : Estimation of the lower bound over iterations

    '''
    if initial_mean is None:
        mu_key, key = split(key, 2)
        mu = initial_std * normal(mu_key, shape=(nfeatures, 1))
    else:
        mu = initial_mean

    b_key, key = split(key, 2)
    b = initial_std * normal(b_key, shape=(nfeatures, 1))
    c = initial_scale * jnp.ones((nfeatures, 1))

    # Variational parameters vector
    variational_params = (mu, b, c)

    # Initial state of the optimizer
    opt_state = optimizer.init(variational_params)

    def sample_fn(variational_params, U_normal):
        mu, b, c = variational_params

        # Parameters in Normal distribution
        epsilon1 = U_normal[0]
        epsilon2 = U_normal[1:].reshape((-1, 1))

        theta = mu + b * epsilon1 + c * epsilon2
        h_theta, grad_h_theta = value_and_grad(logjoint_fn)(theta, data)

        # Gradient of log variational distribution
        grad_log_q = grad_log_q_function(b, c, theta, mu)

        # Gradient of h(theta) and lower bound
        grad_theta = grad_h_theta - grad_log_q

        return grad_theta, epsilon1 * grad_theta, epsilon2 * grad_theta, h_theta

    def iter_fn(all_params, key):
        # Main VB iteration

        variational_params, opt_state = all_params
        mu, b, c = variational_params
        samples = normal(key, shape=(nsamples, nfeatures + 1))

        *grad_lb_iter, lb_first_term = vmap(sample_fn,
                                            in_axes=(None,
                                                     0))(variational_params,
                                                         samples)

        # Estimation of lowerbound
        logdet = jnp.log(jnp.linalg.det(1 + (b / c**2).T @ b)) + jnp.sum(
            jnp.log(c**2))

        # Mean of log-q -> mean(log q(theta))
        lb_log_q = -0.5 * nfeatures * jnp.log(
            2 * jnp.pi) - 0.5 * logdet - nfeatures / 2
        lower_bound = jnp.mean(lb_first_term) - lb_log_q

        # Gradient of log variational distribution
        grad_lb = tree_map(lambda x: x.mean(axis=0), grad_lb_iter)
        grads = compute_natural_gradients(b, c, grad_lb)

        # Gradient clipping
        grads = clip(grads, threshold=threshold)

        updates, opt_state = optimizer.update(grads, opt_state,
                                              variational_params)
        variational_params = optax.apply_updates(variational_params, updates)
        return (variational_params, opt_state), (variational_params,
                                                 lower_bound)

    keys = split(key, niters)
    (best_params, _), (variational_params, lower_bounds) = lax.scan(
        iter_fn, (variational_params, opt_state), keys)

    if window_size is not None:

        def simple_moving_average(cur_sum, i):
            diff = (lower_bounds[i] -
                    lower_bounds[i - window_size]) / window_size
            cur_sum += diff
            return cur_sum, cur_sum

        indices = jnp.arange(window_size, niters)
        cur_sum = jnp.sum(lower_bounds[:window_size]) / window_size
        _, lower_bounds = lax.scan(simple_moving_average, cur_sum, indices)
        lower_bounds = jnp.append(jnp.array([cur_sum]), lower_bounds)

        i = jnp.argmax(lower_bounds) + window_size - 1
        best_params = tree_map(lambda x: x[i], variational_params)

    return best_params, lower_bounds
Exemplo n.º 7
0
                                                   niters=800)
w_ffvb = w_ffvb['params']['Dense_0']['kernel'].squeeze()
lower_triangular = lower_triangular['params']['Dense_0']['kernel']
cov_ffvb = lower_triangular @ lower_triangular.T

# Variational Bayes Low Rank Approximation
(w_lowrank, b, c), lower_bounds = nagvac.vb_gauss_lowrank(
    key,
    partial_logjoint, (Phi, y),
    nfeatures,
    nsamples=20,
    niters=800,
    initial_std=0.1,
    initial_scale=0.3,
    initial_mean=-0.8 + 0.1 * random.normal(key, (nfeatures, 1)),
    optimizer=optax.adafactor(1e-4))

w_lowrank = w_lowrank.squeeze()
cov_lowrank = b @ b.T + jnp.diag(c**2)

# *** Ploting surface predictive distribution ***
colors = ["black" if el else "white" for el in y]
key = random.PRNGKey(31415)
nsamples = 5000

# FFVB surface predictive distribution
ffvb_samples = random.multivariate_normal(key, w_ffvb, cov_ffvb, (nsamples, ))
Z_ffvb = nn.sigmoid(jnp.einsum("mij,sm->sij", Phispace, ffvb_samples))
Z_ffvb = Z_ffvb.mean(axis=0)

# Variational Bayes Low Rank surface predictive distribution
Exemplo n.º 8
0
    return schedule


if __name__ == '__main__':
    # Load the data
    url = 'https://raw.githubusercontent.com/probml/probml-data/main/data/vb_data_labour_force.csv'
    response = requests.get(url)
    rawdata = BytesIO(response.content)
    df = pd.read_csv(rawdata)
    data = df.to_numpy()

    X, y = jnp.array(data[:, :-1]), jnp.array(data[:, -1])

    learning_rate, momentum = 0.001, 0.9
    learning_rate_fn = learning_rate_schedule(learning_rate, 2500)
    optimizer = optax.adafactor(learning_rate_fn, momentum=momentum)

    # prior sigma for mu
    std_init = 0.01

    # Shape of mu, model params
    nfeatures = X.shape[-1]

    # initial scale
    init_scale = 0.1

    niters = 20
    window_size = 50
    num_samples = 200
    threshold = 200