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In this tutorial, you will go over the model lifecycle -- from training to serving -- in the following steps:

  • Training a model using the sklearn example script
  • Serving the model using ClearML Serving
  • Spinning the inference container

The tutorial will also go over these additional options that you can use with clearml-serving:

  • Automatic model deployment
  • Canary endpoints
  • Model performance monitoring


Before executing the steps below, make sure you have completed clearml-serving's initial setup.


Step 1: Train Model

Train a model. Work from your local clearml-serving repository's root.

  • Create a python virtual environment
  • Install the script requirements pip3 install -r examples/sklearn/requirements.txt
  • Execute the training scriptpython3 examples/sklearn/

During execution, ClearML automatically registers the sklearn model and uploads it into the model repository. For information about explicit model registration, see Registering and Deploying New Models Manually.

Step 2: Register Model

Register the new Model on the Serving Service.

clearml-serving --id <service_id> model add --engine sklearn --endpoint "test_model_sklearn" --preprocess "examples/sklearn/" --name "train sklearn model - sklearn-model" --project "serving examples"
Service ID

Make sure that you have executed clearml-serving's initial setup, in which you create a Serving Service. The Serving Service's ID is required to register a model, and to execute clearml-serving's metrics and config commands


The preprocessing python code is packaged and uploaded to the Serving Service, to be used by any inference container, and downloaded in realtime when updated

Step 3: Spin Inference Container

Spin the Inference Container

  • Customize container Dockerfile if needed
  • Build container `
    docker build --tag clearml-serving-inference:latest -f clearml_serving/serving/Dockerfile .
  • Spin the inference container:
    docker run -v ~/clearml.conf:/root/clearml.conf -p 8080:8080 -e CLEARML_SERVING_TASK_ID=<service_id> -e CLEARML_SERVING_POLL_FREQ=5 clearml-serving-inference:latest

Now, test the new model inference endpoint:

curl -X POST "" -H "accept: application/json" -H "Content-Type: application/json" -d '{"x0": 1, "x1": 2}'

Now that you have an inference container running, you can add new model inference endpoints directly with the CLI. The inference container will automatically sync once every 5 minutes. On the first few requests the inference container needs to download the model file and preprocessing python code, this means the request might take a little longer, once everything is cached, it will return almost immediately.


Review the model repository in the ClearML web UI, under the "serving examples" Project on your ClearML account/server (free hosted or self-deployed).

Inference services status, console outputs and machine metrics are available in the ClearML UI in the Serving Service project (default: "DevOps" project)

Registering and Deploying New Models Manually

Uploading an existing model file into the model repository can be done via the clearml RestAPI, the python interface, or with the clearml-serving CLI.

  1. Upload the model file to the clearml-server file storage and register it. The --path parameter is used to input the path to a local model file (local model created in step 1 located in ./sklearn-model.pkl).

    clearml-serving --id <service_id> model upload --name "manual sklearn model" --project "serving examples" --framework "scikitlearn" --path ./sklearn-model.pkl

    You now have a new Model named manual sklearn model in the serving examples project. The CLI output prints the UID of the new model, which you will use to register a new endpoint.

    In the ClearML web UI, the new model is listed under the Models tab of its project. You can also download the model file itself directly from the web UI.

  2. Register a new endpoint with the new model

    clearml-serving --id <service_id> model add --engine sklearn --endpoint "test_model_sklearn" --preprocess "examples/sklearn/" --model-id <newly_created_model_id_here>
Model Storage

You can also provide a different storage destination for the model, such as S3/GS/Azure, by passing --destination="s3://bucket/folder", gs://bucket/folder, azure://bucket/folder. There is no need to provide a unique path to the destination argument, the location of the model will be a unique path based on the serving service ID and the model name

Additional Options

Automatic Model Deployment

The ClearML Serving Service supports automatic model deployment and upgrades, which is connected with the model repository and API. When the model auto-deploy is configured, new model versions will be automatically deployed when you publish or tag a new model in the ClearML model repository. This automation interface allows for simpler CI/CD model deployment process, as a single API automatically deploys (or removes) a model from the Serving Service.

Automatic Model Deployment Example

  1. Configure the model auto-update on the Serving Service

    clearml-serving --id <service_id> model auto-update --engine sklearn --endpoint "test_model_sklearn_auto" --preprocess "" --name "train sklearn model" --project "serving examples" --max-versions 2`
  2. Deploy the Inference container (if not already deployed)

  3. Publish a new model the model repository in one of the following ways:

    • Go to the "serving examples" project in the ClearML web UI, click on the Models Tab, search for "train sklearn model" right-click and select "Publish"
    • Use the RestAPI (see details)
    • Use Python interface:
    from clearml import Model
  4. The new model is available on a new endpoint version (1), test with:

    curl -X POST "" -H "accept: application/json" -H "Content-Type: application/json" -d '{"x0": 1, "x1": 2}'

Canary Endpoint Setup

Canary endpoint deployment adds a new endpoint where the actual request is sent to a preconfigured set of endpoints with pre-provided distribution. For example, let's create a new endpoint "test_model_sklearn_canary", you can provide a list of endpoints and probabilities (weights).

clearml-serving --id <service_id> model canary --endpoint "test_model_sklearn_canary" --weights 0.1 0.9 --input-endpoints test_model_sklearn/2 test_model_sklearn/1

This means that any request coming to /test_model_sklearn_canary/ will be routed with probability of 90% to /test_model_sklearn/1/ and with probability of 10% to /test_model_sklearn/2/.


As with any other Serving Service configuration, you can configure the Canary endpoint while the Inference containers are already running and deployed, they will get updated in their next update cycle (default: once every 5 minutes)

You can also prepare a "fixed" canary endpoint, always splitting the load between the last two deployed models:

clearml-serving --id <service_id> model canary --endpoint "test_model_sklearn_canary" --weights 0.1 0.9 --input-endpoints-prefix test_model_sklearn/

This means that you have two model inference endpoints: /test_model_sklearn/1/ and /test_model_sklearn/2/. The 10% probability (weight 0.1) will match the last (order by version number) endpoint, i.e. /test_model_sklearn/2/, and the 90% will match /test_model_sklearn/2/. When you add a new model endpoint version, e.g. /test_model_sklearn/3/, the canary distribution will automatically match the 90% probability to /test_model_sklearn/2/ and the 10% to the new endpoint /test_model_sklearn/3/.


  1. Add two endpoints:

    clearml-serving --id <service_id> model add --engine sklearn --endpoint "test_model_sklearn" --preprocess "examples/sklearn/" --name "train sklearn model" --version 1 --project "serving examples"
    clearml-serving --id <service_id> model add --engine sklearn --endpoint "test_model_sklearn" --preprocess "examples/sklearn/" --name "train sklearn model" --version 2 --project "serving examples"
  2. Add Canary endpoint:

    clearml-serving --id <service_id> model canary --endpoint "test_model_sklearn_canary" --weights 0.1 0.9 --input-endpoints test_model_sklearn/2 test_model_sklearn/1
  3. Test Canary endpoint:

    curl -X POST "" -H "accept: application/json" -H "Content-Type: application/json" -d '{"x0": 1, "x1": 2}'` 

Model Monitoring and Performance Metrics

Grafana Screenshot

ClearML serving instances send serving statistics (count/latency) automatically to Prometheus and Grafana can be used to visualize and create live dashboards.

The default docker-compose installation is preconfigured with Prometheus and Grafana. Notice that by default data/ate of both containers is not persistent. To add persistence, adding a volume mount is recommended.

You can also add many custom metrics on the input/predictions of your models. Once a model endpoint is registered, adding custom metrics can be done using the CLI.

For example, assume the mock scikit-learn model is deployed on endpoint test_model_sklearn, you can log the requests inputs and outputs (see examples/sklearn/ example):

clearml-serving --id <serving_service_id_here> metrics add --endpoint test_model_sklearn --variable-scalar
x0=0,0.1,0.5,1,10 x1=0,0.1,0.5,1,10 y=0,0.1,0.5,0.75,1

This will create a distribution histogram (buckets specified via a list of less-equal values after = sign), that you will be able to visualize on Grafana.

time-series values

You can also log time-series values with --variable-value x2 or discrete results (e.g. classifications strings) with --variable-enum animal=cat,dog,sheep. Additional custom variables can be added in the preprocess and postprocess with a call to collect_custom_statistics_fn({'new_var': 1.337}). See

With the new metrics logged, you can create a visualization dashboard over the latency of the calls, and the output distribution.

Grafana Model Performance Example

  1. Browse to http://localhost:3000
  2. Login with: admin/admin
  3. Create a new dashboard
  4. Select Prometheus as data source
  5. Add a query: 100 * increase(test_model_sklearn:_latency_bucket[1m]) / increase(test_model_sklearn:_latency_sum[1m])
  6. Change type to heatmap, and select on the right hand-side under "Data Format" select "Time series buckets". You now have the latency distribution, over time.
  7. Repeat the same process for x0, the query would be 100 * increase(test_model_sklearn:x0_bucket[1m]) / increase(test_model_sklearn:x0_sum[1m])

If not specified all serving requests will be logged, which can be changed with the CLEARML_DEFAULT_METRIC_LOG_FREQ environment variable. For example CLEARML_DEFAULT_METRIC_LOG_FREQ=0.2 means only 20% of all requests will be logged. You can also specify per-endpoint log frequency with the clearml-serving CLI. See clearml-serving metrics

Further Examples

See examples of ClearML Serving with other supported frameworks: