Tune: A Scalable Hyperparameter Tuning Library


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Tune is a Python library for hyperparameter tuning at any scale. Core features:

For more information, check out:

  • Code: GitHub repository for Tune.
  • User Guide: A comprehensive overview on how to use Tune’s features.
  • Tutorial Notebooks: Our tutorial notebooks of using Tune with Keras or PyTorch.

Try out a tutorial notebook on Colab:

Tune Tutorial

Quick Start

To run this example, you will need to install the following:

$ pip install ray[tune] torch torchvision filelock

This example runs a small grid search to train a CNN using PyTorch and Tune.

import torch.optim as optim
from ray import tune
from ray.tune.examples.mnist_pytorch import get_data_loaders, ConvNet, train, test

def train_mnist(config):
    train_loader, test_loader = get_data_loaders()
    model = ConvNet()
    optimizer = optim.SGD(model.parameters(), lr=config["lr"])
    for i in range(10):
        train(model, optimizer, train_loader)
        acc = test(model, test_loader)

analysis = tune.run(
    train_mnist, config={"lr": tune.grid_search([0.001, 0.01, 0.1])})

print("Best config: ", analysis.get_best_config(metric="mean_accuracy"))

# Get a dataframe for analyzing trial results.
df = analysis.dataframe()

If TensorBoard is installed, automatically visualize all trial results:

tensorboard --logdir ~/ray_results

If using TF2 and TensorBoard, Tune will also automatically generate TensorBoard HParams output:


Take a look at the Distributed Experiments documentation for:

  1. Setting up distributed experiments on your local cluster
  2. Using AWS and GCP
  3. Spot instance usage/pre-emptible instances, and more.

Open Source Projects using Tune

Here are some of the popular open source repositories and research projects that leverage Tune. Feel free to submit a pull-request adding (or requesting a removal!) of a listed project.

  • Softlearning: Softlearning is a reinforcement learning framework for training maximum entropy policies in continuous domains. Includes the official implementation of the Soft Actor-Critic algorithm.
  • Flambe: An ML framework to accelerate research and its path to production. See flambe.ai.
  • Population Based Augmentation: Population Based Augmentation (PBA) is a algorithm that quickly and efficiently learns data augmentation functions for neural network training. PBA matches state-of-the-art results on CIFAR with one thousand times less compute.
  • Fast AutoAugment by Kakao: Fast AutoAugment (Accepted at NeurIPS 2019) learns augmentation policies using a more efficient search strategy based on density matching.
  • Allentune: Hyperparameter Search for AllenNLP from AllenAI.

Citing Tune

If Tune helps you in your academic research, you are encouraged to cite our paper. Here is an example bibtex:

    title={Tune: A Research Platform for Distributed Model Selection and Training},
    author={Liaw, Richard and Liang, Eric and Nishihara, Robert
            and Moritz, Philipp and Gonzalez, Joseph E and Stoica, Ion},
    journal={arXiv preprint arXiv:1807.05118},