Upgrade hyperparameter tuning to SDK v2
In SDK v2, tuning hyperparameters are consolidated into jobs.
A job has a type. Most jobs are command jobs that run a command, like python main.py. What runs in a job is agnostic to any programming language, so you can run bash scripts, invoke python interpreters, run a bunch of curl commands, or anything else.
A sweep job is another type of job, which defines sweep settings and can be initiated by calling the sweep method of command.
To upgrade, you'll need to change your code for defining and submitting your hyperparameter tuning experiment to SDK v2. What you run within the job doesn't need to be upgraded to SDK v2. However, it's recommended to remove any code specific to Azure Machine Learning from your model training scripts. This separation allows for an easier transition between local and cloud and is considered best practice for mature MLOps. In practice, this means removing azureml.* lines of code. Model logging and tracking code should be replaced with MLflow. For more information, see how to use MLflow in v2.
This article gives a comparison of scenario(s) in SDK v1 and SDK v2.
Run hyperparameter tuning in an experiment
SDK v1
from azureml.core import ScriptRunConfig, Experiment, Workspace from azureml.train.hyperdrive import RandomParameterSampling, BanditPolicy, HyperDriveConfig, PrimaryMetricGoal from azureml.train.hyperdrive import choice, loguniform dataset = Dataset.get_by_name(ws, 'mnist-dataset') # list the files referenced by mnist dataset dataset.to_path() #define the search space for your hyperparameters param_sampling = RandomParameterSampling( { '--batch-size': choice(25, 50, 100), '--first-layer-neurons': choice(10, 50, 200, 300, 500), '--second-layer-neurons': choice(10, 50, 200, 500), '--learning-rate': loguniform(-6, -1) } ) args = ['--data-folder', dataset.as_named_input('mnist').as_mount()] #Set up your script run src = ScriptRunConfig(source_directory=script_folder, script='keras_mnist.py', arguments=args, compute_target=compute_target, environment=keras_env) # Set early stopping on this one early_termination_policy = BanditPolicy(evaluation_interval=2, slack_factor=0.1) # Define the configurations for your hyperparameter tuning experiment hyperdrive_config = HyperDriveConfig(run_config=src, hyperparameter_sampling=param_sampling, policy=early_termination_policy, primary_metric_name='Accuracy', primary_metric_goal=PrimaryMetricGoal.MAXIMIZE, max_total_runs=20, max_concurrent_runs=4) # Specify your experiment details experiment = Experiment(workspace, experiment_name) hyperdrive_run = experiment.submit(hyperdrive_config) #Find the best model best_run = hyperdrive_run.get_best_run_by_primary_metric()SDK v2
from azure.ai.ml import MLClient from azure.ai.ml import command, Input from azure.ai.ml.sweep import Choice, Uniform, MedianStoppingPolicy from azure.identity import DefaultAzureCredential # Create your command command_job_for_sweep = command( code="./src", command="python main.py --iris-csv ${{inputs.iris_csv}} --learning-rate ${{inputs.learning_rate}} --boosting ${{inputs.boosting}}", environment="AzureML-lightgbm-3.2-ubuntu18.04-py37-cpu@latest", inputs={ "iris_csv": Input( type="uri_file", path="https://azuremlexamples.blob.core.windows.net/datasets/iris.csv", ), #define the search space for your hyperparameters "learning_rate": Uniform(min_value=0.01, max_value=0.9), "boosting": Choice(values=["gbdt", "dart"]), }, compute="cpu-cluster", ) # Call sweep() on your command job to sweep over your parameter expressions sweep_job = command_job_for_sweep.sweep( compute="cpu-cluster", sampling_algorithm="random", primary_metric="test-multi_logloss", goal="Minimize", ) # Define the limits for this sweep sweep_job.set_limits(max_total_trials=20, max_concurrent_trials=10, timeout=7200) # Set early stopping on this one sweep_job.early_termination = MedianStoppingPolicy(delay_evaluation=5, evaluation_interval=2) # Specify your experiment details sweep_job.display_name = "lightgbm-iris-sweep-example" sweep_job.experiment_name = "lightgbm-iris-sweep-example" sweep_job.description = "Run a hyperparameter sweep job for LightGBM on Iris dataset." # submit the sweep returned_sweep_job = ml_client.create_or_update(sweep_job) # get a URL for the status of the job returned_sweep_job.services["Studio"].endpoint # Download best trial model output ml_client.jobs.download(returned_sweep_job.name, output_name="model")
Run hyperparameter tuning in a pipeline
SDK v1
tf_env = Environment.get(ws, name='AzureML-TensorFlow-2.0-GPU') data_folder = dataset.as_mount() src = ScriptRunConfig(source_directory=script_folder, script='tf_mnist.py', arguments=['--data-folder', data_folder], compute_target=compute_target, environment=tf_env) #Define HyperDrive configs ps = RandomParameterSampling( { '--batch-size': choice(25, 50, 100), '--first-layer-neurons': choice(10, 50, 200, 300, 500), '--second-layer-neurons': choice(10, 50, 200, 500), '--learning-rate': loguniform(-6, -1) } ) early_termination_policy = BanditPolicy(evaluation_interval=2, slack_factor=0.1) hd_config = HyperDriveConfig(run_config=src, hyperparameter_sampling=ps, policy=early_termination_policy, primary_metric_name='validation_acc', primary_metric_goal=PrimaryMetricGoal.MAXIMIZE, max_total_runs=4, max_concurrent_runs=4) metrics_output_name = 'metrics_output' metrics_data = PipelineData(name='metrics_data', datastore=datastore, pipeline_output_name=metrics_output_name, training_output=TrainingOutput("Metrics")) model_output_name = 'model_output' saved_model = PipelineData(name='saved_model', datastore=datastore, pipeline_output_name=model_output_name, training_output=TrainingOutput("Model", model_file="outputs/model/saved_model.pb")) #Create HyperDriveStep hd_step_name='hd_step01' hd_step = HyperDriveStep( name=hd_step_name, hyperdrive_config=hd_config, inputs=[data_folder], outputs=[metrics_data, saved_model]) #Find and register best model conda_dep = CondaDependencies() conda_dep.add_pip_package("azureml-sdk") rcfg = RunConfiguration(conda_dependencies=conda_dep) register_model_step = PythonScriptStep(script_name='register_model.py', name="register_model_step01", inputs=[saved_model], compute_target=cpu_cluster, arguments=["--saved-model", saved_model], allow_reuse=True, runconfig=rcfg) register_model_step.run_after(hd_step) #Run the pipeline pipeline = Pipeline(workspace=ws, steps=[hd_step, register_model_step]) pipeline_run = exp.submit(pipeline)SDK v2
train_component_func = load_component(path="./train.yml") score_component_func = load_component(path="./predict.yml") # define a pipeline @pipeline() def pipeline_with_hyperparameter_sweep(): """Tune hyperparameters using sample components.""" train_model = train_component_func( data=Input( type="uri_file", path="wasbs://datasets@azuremlexamples.blob.core.windows.net/iris.csv", ), c_value=Uniform(min_value=0.5, max_value=0.9), kernel=Choice(["rbf", "linear", "poly"]), coef0=Uniform(min_value=0.1, max_value=1), degree=3, gamma="scale", shrinking=False, probability=False, tol=0.001, cache_size=1024, verbose=False, max_iter=-1, decision_function_shape="ovr", break_ties=False, random_state=42, ) sweep_step = train_model.sweep( primary_metric="training_f1_score", goal="minimize", sampling_algorithm="random", compute="cpu-cluster", ) sweep_step.set_limits(max_total_trials=20, max_concurrent_trials=10, timeout=7200) score_data = score_component_func( model=sweep_step.outputs.model_output, test_data=sweep_step.outputs.test_data ) pipeline_job = pipeline_with_hyperparameter_sweep() # set pipeline level compute pipeline_job.settings.default_compute = "cpu-cluster" # submit job to workspace pipeline_job = ml_client.jobs.create_or_update( pipeline_job, experiment_name="pipeline_samples" ) pipeline_job
Mapping of key functionality in SDK v1 and SDK v2
| Functionality in SDK v1 | Rough mapping in SDK v2 |
|---|---|
| HyperDriveRunConfig() | SweepJob() |
| hyperdrive Package | sweep Package |
Next steps
For more information, see: