Overriding compute resources

For background on compute resources, see Compute Resources in Tekton.

Konflux tasks have default resource requests and limits. Some set them explicitly in the Task definition, others inherit them from the LimitRange in your namespace.

If the default resources do not meet your needs, you can take advantage of Tekton’s taskRunSpecs to override them. You can configure taskRunSpecs in the PipelineRun files in your .tekton directory. For example:

kind: PipelineRun
spec:
  taskRunSpecs:
    - pipelineTaskName: build-container
      stepSpecs:
        - name: build
          computeResources:
            requests:
              memory: 10Gi
            limits:
              memory: 10Gi

    - pipelineTaskName: prefetch-dependencies
      computeResources:
        requests:
          cpu: '1'
          memory: 2Gi
        limits:
          memory: 2Gi

  pipelineSpec:
    tasks:
      # ...
      - name: prefetch-dependencies
        taskRef: ...
      # ...
      - name: build-container
        taskRef:
          resolver: bundles
          params:
            - name: kind
              value: task
            - name: name
              value: buildah
            - name: bundle
              value: quay.io/konflux-ci/tekton-catalog/task-buildah:0.2

This PipelineRun:

Overrides the resources for the build step in the build-container task. Other steps in the build-container task are not affected.
Sets the overall resources for the prefetch-dependencies task. Tekton divides the resources equally among all the steps in the task. If the prefetch task has two steps, each will receive 500m cpu and 1Gi memory.

When overriding the resources for a specific step, you need to know the name of the step. You can find the names of all steps in the Task definition. If your Pipeline references the task as a bundle (like the example above), you can use the tkn tool to see the Task definition:

tkn bundle list -o yaml quay.io/konflux-ci/tekton-catalog/task-buildah:0.2

To set the overall resources, we use task-level computeResources. To set the resources for a specific step, we use stepSpecs.

As of Tekton Pipelines v0.61.0, task-level computeResources are a Beta feature and stepSpecs are an Alpha feature. These features may not be enabled for your Tekton installation, confirm with your cluster administrator. See the Tekton documentation on Beta Features and Alpha Features.