Fine-tuning a model with the 🤗 TLC Trainer API

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This notebook demonstrates how to use our hugging face TLC Trainer API and finetuning a model called bert-base-uncased

PROJECT_NAME = "bert-base-uncased"
RUN_NAME = "finetuning-run"
DESCRIPTION = "Fine-tuning BERT on MRPC"
TRAIN_DATASET_NAME = "hugging-face-train"
VAL_DATASET_NAME = "hugging-face-val"
CHECKPOINT = "bert-base-uncased"
DEVICE = None
TRAIN_BATCH_SIZE = 64
EVAL_BATCH_SIZE = 256
EPOCHS = 4
OPTIMIZER = "adamw_torch"
TRANSIENT_DATA_PATH = "../transient_data"
TLC_PUBLIC_EXAMPLES_DEVELOPER_MODE = True
INSTALL_DEPENDENCIES = False

%%capture
if INSTALL_DEPENDENCIES:
    %pip --quiet install torch --index-url https://download.pytorch.org/whl/cu118
    %pip --quiet install torchvision --index-url https://download.pytorch.org/whl/cu118
    %pip --quiet install accelerate
    %pip --quiet install scikit-learn
    %pip --quiet install 3lc[huggingface]

import os

import datasets
import evaluate
import numpy as np
import torch
from transformers import AutoModelForSequenceClassification, AutoTokenizer, DataCollatorWithPadding, TrainingArguments

import tlc

os.environ["TRANSFORMERS_NO_ADVISORY_WARNINGS"] = "true"  # Removing BertTokenizerFast tokenizer warning

datasets.utils.logging.disable_progress_bar()

if DEVICE is None:
    if torch.cuda.is_available():
        DEVICE = "cuda"
    elif torch.backends.mps.is_available():
        DEVICE = "mps"
    else:
        DEVICE = "cpu"

Initialize a 3LC Run

We initialize a Run with a call to tlc.init, and add the configuration to the Run object.

run = tlc.init(
    project_name=PROJECT_NAME,
    run_name=RUN_NAME,
    description=DESCRIPTION,
    if_exists="overwrite",
)

With the 3LC integration, you can use tlc.Table.from_hugging_face() as a drop-in replacement for datasets.load_dataset() to create a tlc.Table. Notice .latest(), which gets the latest version of the 3LC dataset.

tlc_train_dataset = tlc.Table.from_hugging_face(
    "glue",
    "mrpc",
    split="train",
    project_name=PROJECT_NAME,
    dataset_name=TRAIN_DATASET_NAME,
    if_exists="overwrite",
).latest()

tlc_val_dataset = tlc.Table.from_hugging_face(
    "glue",
    "mrpc",
    split="validation",
    project_name=PROJECT_NAME,
    dataset_name=VAL_DATASET_NAME,
    if_exists="overwrite",
).latest()

Table provides a method map to apply both preprocessing and on-the-fly transforms to your data before it is sent to the model.

It is different from huggingface where it generates a new reference of the data directly including the example

tokenizer = AutoTokenizer.from_pretrained(CHECKPOINT)


def tokenize_function_tlc(example):
    return {**example, **tokenizer(example["sentence1"], example["sentence2"], truncation=True)}


tlc_tokenized_dataset_train = tlc_train_dataset.map(tokenize_function_tlc)
tlc_tokenized_dataset_val = tlc_val_dataset.map(tokenize_function_tlc)

data_collator = DataCollatorWithPadding(tokenizer=tokenizer)

Here we define our model with two labels

# For demonstration purposes, we use the bert-base-uncased model with a different set of labels than
# it was trained on. As a result, there will be a warning about the inconsistency of the classifier and
# pre_classifier weights. This is expected and can be ignored.
model = AutoModelForSequenceClassification.from_pretrained(CHECKPOINT, num_labels=2)

Setup Metrics Collection

Computing metrics is done by implementing a function which returns per-sample metrics you would like to see in the 3LC Dashboard.

This is different from the original compute_metrics of Huggingface which compute per batch the metrics. Here we want to find results with a granularity of per sample basis.

def compute_tlc_metrics(logits, labels):
    probabilities = torch.nn.functional.softmax(logits, dim=-1)

    predictions = logits.argmax(dim=-1)
    loss = torch.nn.functional.cross_entropy(logits, labels, reduction="none")
    confidence = probabilities.gather(dim=-1, index=predictions.unsqueeze(-1)).squeeze()

    return {
        "predicted": predictions,
        "loss": loss,
        "confidence": confidence,
    }


id2label = {0: "not_equivalent", 1: "equivalent"}
schemas = {
    "predicted": tlc.CategoricalLabelSchema(
        display_name="Predicted Label", class_names=id2label.values(), display_importance=4005
    ),
    "loss": tlc.Schema(display_name="Loss", writable=False, value=tlc.Float32Value()),
    "confidence": tlc.Schema(display_name="Confidence", writable=False, value=tlc.Float32Value()),
}
compute_tlc_metrics.column_schemas = schemas

# Add references to the input datasets used by the Run.
run.add_input_table(tlc_train_dataset)
run.add_input_table(tlc_val_dataset)

Train the model with TLCTrainer

To perform model training, we replace the usual Trainer with TLCTrainer and provide the per-sample metrics collection function.

In this example, we still compute the glue MRPC per batch thanks to the compute_hf_metrics method (compute_metrics is changed to compute_hf_metrics to avoid confusion).

We also compute our special per sample tlc metrics thanks to the compute_tlc_metrics method.

With this latter, we can choose when to start to collect the metrics, here at epoch 2 (indexed from 0 with tlc_metrics_collection_start) with a frequency of 1 epoch (with tlc_metrics_collection_epoch_frequency).

You also can switch the strategy to compute the metrics to “steps” in the eval_strategy and specify the frequency with eval_steps. At this stage, if you use tlc_metrics_collection_start, it should be a multiple of eval_steps. Note that tlc_metrics_collection_epoch_frequency is disable in this case because we use the original eval_steps variable.

We also specify that we would like to collect metrics prior to training with compute_tlc_metrics_on_train_begin.

from tlc.integration.hugging_face import TLCTrainer


def compute_metrics(eval_preds):
    metric = evaluate.load("glue", "mrpc")
    logits, labels = eval_preds
    predictions = np.argmax(logits, axis=-1)
    return metric.compute(predictions=predictions, references=labels)


training_args = TrainingArguments(
    output_dir=TRANSIENT_DATA_PATH,
    per_device_train_batch_size=TRAIN_BATCH_SIZE,
    per_device_eval_batch_size=EVAL_BATCH_SIZE,
    optim=OPTIMIZER,
    num_train_epochs=EPOCHS,
    report_to="none",  # Disable wandb logging
    use_cpu=DEVICE == "cpu",
    eval_strategy="epoch",
    disable_tqdm=True,
    # eval_strategy="steps",  # For running metrics on steps
    # eval_steps=20,  # For running metrics on steps
)

trainer = TLCTrainer(
    model=model,
    args=training_args,
    train_dataset=tlc_tokenized_dataset_train,
    eval_dataset=tlc_tokenized_dataset_val,
    tokenizer=tokenizer,
    data_collator=data_collator,
    compute_hf_metrics=compute_metrics,
    compute_tlc_metrics=compute_tlc_metrics,
    compute_tlc_metrics_on_train_begin=True,
    compute_tlc_metrics_on_train_end=False,
    tlc_metrics_collection_start=2,
    tlc_metrics_collection_epoch_frequency=1,
)

trainer.train()