Run text classification with Amazon SageMaker JumpStart using TensorFlow Hub and Hugging Face models

In December 2020, AWS announced the general availability of Amazon SageMaker JumpStart, a capability of Amazon SageMaker that helps you quickly and easily get started with machine learning (ML). JumpStart provides one-click fine-tuning and deployment of a wide variety of pre-trained models across popular ML tasks, as well as a selection of end-to-end solutions that solve common business problems. These features remove the heavy lifting from each step of the ML process, making it easier to develop high-quality models and reducing time to deployment.

All JumpStart content was previously available only through Amazon SageMaker Studio, which provides a user-friendly graphical interface to interact with the feature. Recently, we also announced the launch of easy-to-use JumpStart APIs as an extension of the SageMaker Python SDK, allowing you to programmatically deploy and fine-tune a vast selection of JumpStart-supported pre-trained models on your own datasets. This launch unlocks the usage of JumpStart capabilities in your code workflows, MLOps pipelines, and anywhere else you are interacting with SageMaker via SDK.

This post is the second in a series on using JumpStart for specific tasks. In the first post, we showed how you can run image classification use cases on JumpStart. In this post, we provide a step-by-step walkthrough on how to fine-tune and deploy a text classification model, using trained models from TensorFlow Hub. We explore two ways of obtaining the same result: via JumpStart’s graphical interface on Studio, and programmatically through JumpStart APIs. While not used in this blog post, Amazon Comprehend is a natural language processing (NLP) service that uses machine learning (ML) to find insights and relationships like people, places, sentiments, and topics in text. In a fully-managed experience, customers can use Comprehend’s custom classification API to train a custom classification model to recognize the classes that are of interest and then use that model to classify documents into your own categories.

If you want to jump straight into the JumpStart API code we explain in this post, you can refer to the following sample Jupyter notebooks:

• Introduction to JumpStart – Text Classification
• Introduction to JumpStart – Sentence Pair Classification

JumpStart overview

JumpStart is a multi-faceted product that includes different capabilities to help get you quickly started with ML on SageMaker. At the time of writing, JumpStart enables you to do the following:

• Deploy pre-trained models for common ML tasks – JumpStart enables you to address common ML tasks with no development effort by providing easy deployment of models pre-trained on large, publicly available datasets. The ML research community has put a large amount of effort into making a majority of recently developed models publicly available for use. JumpStart hosts a collection of over 300 models, spanning the 15 most popular ML tasks such as object detection, text classification, and text generation, making it easy for beginners to use them. These models are drawn from popular model hubs such as TensorFlow, PyTorch, Hugging Face, and MXNet Hub.
• Fine-tune pre-trained models – JumpStart allows you to fine-tune pre-trained models with no need to write your own training algorithm. In ML, the ability to transfer the knowledge learned in one domain to another domain is called transfer learning. You can use transfer learning to produce accurate models on your smaller datasets, with much lower training costs than the ones involved in training the original model. JumpStart also includes popular training algorithms based on LightGBM, CatBoost, XGBoost, and Scikit-learn, which you can train from scratch for tabular regression and classification.
• Use pre-built solutions – JumpStart provides a set of 17 solutions for common ML use cases, such as demand forecasting and industrial and financial applications, which you can deploy with just a few clicks. Solutions are end-to-end ML applications that string together various AWS services to solve a particular business use case. They use AWS CloudFormation templates and reference architectures for quick deployment, which means they’re fully customizable.
• Refer to notebook examples for SageMaker algorithms – SageMaker provides a suite of built-in algorithms to help data scientists and ML practitioners get started with training and deploying ML models quickly. JumpStart provides sample notebooks that you can use to quickly use these algorithms.
• Review training videos and blogs – JumpStart also provides numerous blog posts and videos that teach you how to use different functionalities within SageMaker.

JumpStart accepts custom VPC settings and AWS Key Management Service (AWS KMS) encryption keys, so you can use the available models and solutions securely within your enterprise environment. You can pass your security settings to JumpStart within Studio or through the SageMaker Python SDK.

Transformer models and the importance of fine-tuning

The attention-based Transformer architecture has become the de-facto standard for the state-of-the-art natural language processing (NLP) models. In 2018, the famous BERT model was born from an adapted Transformer encoder, pre-trained on GBs of unlabeled English text from Wikipedia and other public resources. BERT was incredibly useful for creating contextualized text representations, which you could then use in many downstream tasks by fine-tuning the model. Since then, many variants of the BERT model have been developed by way of architecture, pre-training schema, or pre-training dataset changes.

Fine-tuning means to use a model that has been pre-trained on a given task and train it again, this time for a specific task that is different but related (and on your specific data). This practice is also typically referred to as transfer learning—literally meaning to transfer knowledge gained on one task to another. Typically, Transformer-based models are pre-trained on massive amounts of unlabeled data, and comparatively much smaller labeled datasets are then used for fine-tuning. Being able to leverage the large computational investments made to pre-train such models for downstream tasks (commonly made open-source) has been one of the most important factors in the growth of NLP as a field in previous years. However, as new models get larger and more complex, so does the development effort required to fine-tune and deploy them efficiently. In this post, we show you how to use JumpStart to fine-tune a BERT model with little to no development effort involved.

Text classification

Sentiment analysis is one of the many tasks under the umbrella of text classification. It consists of predicting what sentiment should be assigned to a specific passage of text, with varying degrees of granularity. Typical applications include social media monitoring, customer support management, and analyzing customer feedback.

The input is a directory containing a data.csv file. The first column is the label (an integer between 0 and the number of classes in the dataset), and the second column is the corresponding passage of text. This means that you could even use a dataset with more degrees of sentiment than the original—for example, very negative (0), negative (1), neutral (2), positive (3), very positive (4). The following is an example of a data.csv file corresponding to the SST2 (Stanford Sentiment Treebank) dataset, and shows values in its first two columns. Note that the file shouldn’t have any header.

The SST2^1,2 dataset is downloaded from TensorFlow. Apache 2.0 License. Dataset Homepage.

Sentence pair classification

Sentence pair classification consists of predicting a class for a pair of sentences, which forces the model to learn semantic dependencies between sentence pairs. Among these are typically textual entailment (does the first sentence come before the second originally?), paraphrasing (are both sentences just differently worded versions of one another?), and others.

The input is a directory containing a data.csv file. The first column in the file should have integer class labels between 0 and the number of classes. The second and third columns should contain the first and second sentence corresponding to that row. The following is an example of a data.csv file for the QNLI dataset, and shows values in its first three columns. Note that the file shouldn’t have any header.

The QNLI^3.4 dataset is downloaded from TensorFlow. Apache 2.0 License. Dataset Homepage. CC BY-SA 4.0 License.

Solution overview

The following sections provide a step-by-step demo to perform sentiment analysis with JumpStart, both via the Studio UI and via JumpStart APIs. The workflow for sentence pair classification is almost identical, and we describe the changes required for that task.

We walk through the following steps:

1. Access JumpStart through the Studio UI:
   1. Fine-tune the pre-trained model.
   2. Deploy the fine-tuned model.
2. Use JumpStart programmatically with the SageMaker Python SDK:
   1. Fine-tune the pre-trained model.
   2. Deploy the fine-tuned model.

Access JumpStart through the Studio UI

In this section, we demonstrate how to train and deploy JumpStart models through the Studio UI.

Fine-tune the pre-trained model

The following video shows you how to find a pre-trained text classification model on JumpStart and fine-tune it on the task of sentiment analysis. The model page contains valuable information about the model, how to use it, expected data format, and some fine-tuning details.

For demonstration purposes, we fine-tune the model using the dataset provided by default, which is the Stanford Sentiment Treebank v2 (SST2) dataset. Fine-tuning on your own dataset involves taking the correct formatting of data (as explained on the model page), uploading it to Amazon Simple Storage Service (Amazon S3), and specifying its location in the data source configuration.

We use the sane hyperparameter values set by default (number of epochs, learning rate, and batch size). We also use a GPU-backed ml.p3.2xlarge as our SageMaker training instance.

You can monitor your training job running directly on the Studio console, and are notified upon its completion.

For sentence pair classification, instead of searching for text classification models in the JumpStart search bar, search for sentence pair classification. For example, choose Bert Base Uncased from the resulting model selection. Apart from the dataset format, the rest of the workflow is identical between text classification and sentence pair classification.

Deploy the fine-tuned model

After training is complete, you can deploy the fine-tuned model from the same page that holds the training job details. To deploy our model, we pick a different instance type, ml.g4dn.xlarge. It still provides the GPU acceleration needed for low inference latency, but at a lower price point. After you configure the SageMaker hosting instance, choose Deploy. It may take 5–10 minutes until your persistent endpoint is up and running.

After a few minutes, your endpoint is operational and ready to respond to inference requests!

To accelerate your time to inference, JumpStart provides a sample notebook that shows you how to run inference on your freshly deployed endpoint. Choose Open Notebook under Use Endpoint from Studio.

Use JumpStart programmatically with the SageMaker SDK

In the preceding sections, we showed how you can use the JumpStart UI to fine-tune and deploy a model interactively, in a matter of a few clicks. However, you can also use JumpStart’s models and easy fine-tuning programmatically by using APIs that are integrated into the SageMaker SDK. We now go over a quick example of how you can replicate the preceding process. All the steps in this demo are available in the accompanying notebooks Introduction to JumpStart – Text Classification and Introduction to JumpStart – Sentence Pair Classification.

Fine-tune the pre-trained model

To fine-tune a selected model, we need to get that model’s URI, as well as that of the training script and the container image used for training. Thankfully, these three inputs depend solely on the model name, version (for a list of the available models, see JumpStart Available Model Table), and the type of instance you want to train on. This is demonstrated in the following code snippet:

from sagemaker import image_uris, model_uris, script_uris

model_id, model_version = "tensorflow-tc-bert-en-uncased-L-12-H-768-A-12-2", "1.0.0"
training_instance_type = "ml.p3.2xlarge"

# Retrieve the docker image
train_image_uri = image_uris.retrieve(
    region=None,
    framework=None,
    model_id=model_id,
    model_version=model_version,
    image_scope="training",
    instance_type=training_instance_type,
)
# Retrieve the training script

train_source_uri = script_uris.retrieve(model_id=model_id, model_version=model_version, script_scope="training")

# Retrieve the pre-trained model tarball to further fine-tune

train_model_uri = model_uris.retrieve(model_id=model_id, model_version=model_version, model_scope="training")

We retrieve the model_id corresponding to the same model we used previously (dimensions are characteristic to the base version of BERT). The tc in the identifier corresponds to text classification.

For sentence pair classification, we can set model_id to huggingface-spc-bert-base-uncased. The spc in the identifier corresponds to sentence pair classification.

You can now fine-tune this JumpStart model on your own custom dataset using the SageMaker SDK. We use a dataset that is publicly hosted on Amazon S3, conveniently focused on sentiment analysis. The dataset should be structured for fine-tuning as explained in the previous section. See the following example code:

# URI of your training dataset
training_dataset_s3_path = "s3://jumpstart-cache-prod-us-west-2/training-datasets/tc/data.csv"
training_job_name = name_from_base(f"jumpstart-example-{model_id}-transfer-learning")

# Create SageMaker Estimator instance
tc_estimator = Estimator(
    role=aws_role,
    image_uri=train_image_uri,
    source_dir=train_source_uri,
    model_uri=train_model_uri,
    entry_point="transfer_learning.py",
    instance_count=1,
    instance_type=training_instance_type,
    max_run=360000,
    hyperparameters=hyperparameters,
    output_path=s3_output_location,
)

# Launch a SageMaker Training job by passing s3 path of the training data
tc_estimator.fit({"training": training_dataset_s3_path}, logs=True)

We obtain the same default hyperparameters for our selected model as the ones we saw in the previous section, using sagemaker.hyperparameters.retrieve_default(). We then instantiate a SageMaker estimator, and call the .fit method to start fine-tuning our model, passing it the Amazon S3 URI for our training data. As you can see, the entry_point script provided is named transfer_learning.py (the same for other tasks and models), and the input data channel passed to .fit must be named training.

Deploy the fine-tuned model

When training is complete, you can deploy your fine-tuned model. To do so, all we need to obtain is the inference script URI (the code that determines how the model is used for inference once deployed) and the inference container image URI, which includes an appropriate model server to host the model we chose. See the following code:

# Retrieve the inference docker container uri
deploy_image_uri = image_uris.retrieve(
    region=None,
    framework=None,
    image_scope="inference",
    model_id=model_id,
    model_version=model_version,
    instance_type=inference_instance_type,
)
# Retrieve the inference script uri
deploy_source_uri = script_uris.retrieve(
    model_id=model_id, model_version=model_version, script_scope="inference"
)

endpoint_name = name_from_base(f"jumpstart-example-FT-{model_id}-")

# Use the estimator from the previous step to deploy to a SageMaker endpoint
finetuned_predictor = tc_estimator.deploy(
    initial_instance_count=1,
    instance_type=inference_instance_type,
    entry_point="inference.py",
    image_uri=deploy_image_uri,
    source_dir=deploy_source_uri,
    endpoint_name=endpoint_name,
)

After a few minutes, our model is deployed and we can get predictions from it in real time!

Next, we invoke the endpoint to predict the sentiment of the example text. We use the query_endpoint and parse_response helper functions, which are defined in the accompanying notebook:

text = "simply stupid , irrelevant and deeply , truly , bottomlessly cynical "
query_response = query_endpoint(text.encode("utf-8"))
probabilities, labels, predicted_label = parse_response(query_response)

Conclusion

JumpStart is a capability in SageMaker that allows you to quickly get started with ML. JumpStart uses open-source pre-trained models to solve common ML problems like image classification, object detection, text classification, sentence pair classification, and question answering.

In this post, we showed you how to fine-tune and deploy a pre-trained text classification model for sentiment analysis. We also mentioned the changes required to adapt the demo for sentence pair classification. With JumpStart, you can easily do this process with no need to code. Try out the solution on your own and let us know how it goes in the comments. To learn more about JumpStart, check out the AWS re:Invent 2020 video Get started with ML in minutes with Amazon SageMaker JumpStart.

References

1. Socher et al., 2013
2. Wang et al., 2018a
3. Rajpurkar et al., 2016
4. Wang et al., 2018a

About the Authors

João Moura is an AI/ML Specialist Solutions Architect at Amazon Web Services. He is mostly focused on NLP use cases and helping customers optimize Deep Learning model training and deployment. He is also an active proponent of low-code ML solutions and ML-specialized hardware.

Dr. Vivek Madan is an Applied Scientist with Amazon SageMaker JumpStart team. He got his PhD from University of Illinois at Urbana-Champaign and was a Post Doctoral Researcher at Georgia Tech. He is an active researcher in machine learning and algorithm design and has published papers in EMNLP, ICLR, COLT, FOCS and SODA conferences.

Dr. Ashish Khetan is a Senior Applied Scientist with Amazon SageMaker JumpStart and Amazon SageMaker built-in algorithms and helps develop machine learning algorithms. He is an active researcher in machine learning and statistical inference and has published many papers in NeurIPS, ICML, ICLR, JMLR, ACL, and EMNLP conferences.

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