Cluster Loader is a tool that deploys large numbers of various objects to a cluster, which creates user-defined cluster objects. Build, configure, and run Cluster Loader to measure performance metrics of your OpenShift Container Platform deployment at various cluster states.

Installing Cluster Loader

Cluster Loader is included in the origin-tests container image.

Procedure
  1. To pull the origin-tests container image, run:

    $ sudo podman pull quay.io/openshift/origin-tests:4.2

Running Cluster Loader

Procedure
  1. Execute Cluster Loader using the built-in test configuration, which deploys five template builds and waits for them to complete:

    $ sudo podman run -v ${LOCAL_KUBECONFIG}:/root/.kube/config:z -i \
    quay.io/openshift/origin-tests:4.2 /bin/bash -c 'export KUBECONFIG=/root/.kube/config && \
    openshift-tests run-test "[Feature:Performance][Serial][Slow] Load cluster should load the \
    cluster [Suite:openshift]"'

    Alternatively, execute Cluster Loader with a user-defined configuration by setting the environment variable for VIPERCONFIG:

    $ sudo podman run -v ${LOCAL_KUBECONFIG}:/root/.kube/config:z \
    -v ${LOCAL_CONFIG_FILE_PATH}:/root/configs/:z \
    -i quay.io/openshift/origin-tests:4.2 \
    /bin/bash -c 'KUBECONFIG=/root/.kube/config VIPERCONFIG=/root/configs/test.yaml \
    openshift-tests run-test "[Feature:Performance][Serial][Slow] Load cluster should \
    load the cluster [Suite:openshift]"'

    In this example, ${LOCAL_KUBECONFIG} refers to the path to the kubeconfig on your local file system. Also, there is a directory called ${LOCAL_CONFIG_FILE_PATH}, which is mounted into the container that contains a configuration file called test.yaml. Additionally, if the test.yaml references any external template files or podspec files, they should also be mounted into the container.

Configuring Cluster Loader

The tool creates multiple namespaces (projects), which contain multiple templates or Pods.

Example Cluster Loader configuration file

Cluster Loader’s configuration file is a basic YAML file:

provider: local (1)
ClusterLoader:
  cleanup: true
  projects:
    - num: 1
      basename: clusterloader-cakephp-mysql
      tuning: default
      ifexists: reuse
      templates:
        - num: 1
          file: cakephp-mysql.json

    - num: 1
      basename: clusterloader-dancer-mysql
      tuning: default
      ifexists: reuse
      templates:
        - num: 1
          file: dancer-mysql.json

    - num: 1
      basename: clusterloader-django-postgresql
      tuning: default
      ifexists: reuse
      templates:
        - num: 1
          file: django-postgresql.json

    - num: 1
      basename: clusterloader-nodejs-mongodb
      tuning: default
      ifexists: reuse
      templates:
        - num: 1
          file: quickstarts/nodejs-mongodb.json

    - num: 1
      basename: clusterloader-rails-postgresql
      tuning: default
      templates:
        - num: 1
          file: rails-postgresql.json

  tuningsets: (2)
    - name: default
      pods:
        stepping: (3)
          stepsize: 5
          pause: 0 s
        rate_limit: (4)
          delay: 0 ms
1 Optional setting for end-to-end tests. Set to local to avoid extra log messages.
2 The tuning sets allow rate limiting and stepping, the ability to create several batches of Pods while pausing in between sets. Cluster Loader monitors completion of the previous step before continuing.
3 Stepping will pause for M seconds after each N objects are created.
4 Rate limiting will wait M milliseconds between the creation of objects.

This example assumes that references to any external template files or podspec files are also mounted into the container.

Configuration fields

Table 1. Top-level Cluster Loader Fields
Field Description

cleanup

Set to true or false. One definition per configuration. If set to true, cleanup deletes all namespaces (projects) created by Cluster Loader at the end of the test.

projects

A sub-object with one or many definition(s). Under projects, each namespace to create is defined and projects has several mandatory subheadings.

tuningsets

A sub-object with one definition per configuration. tuningsets allows the user to define a tuning set to add configurable timing to project or object creation (Pods, templates, and so on).

sync

An optional sub-object with one definition per configuration. Adds synchronization possibilities during object creation.

Table 2. Fields under projects
Field Description

num

An integer. One definition of the count of how many projects to create.

basename

A string. One definition of the base name for the project. The count of identical namespaces will be appended to Basename to prevent collisions.

tuning

A string. One definition of what tuning set you want to apply to the objects, which you deploy inside this namespace.

ifexists

A string containing either reuse or delete. Defines what the tool does if it finds a project or namespace that has the same name of the project or namespace it creates during execution.

configmaps

A list of key-value pairs. The key is the ConfigMap name and the value is a path to a file from which you create the ConfigMap.

secrets

A list of key-value pairs. The key is the secret name and the value is a path to a file from which you create the secret.

pods

A sub-object with one or many definition(s) of Pods to deploy.

templates

A sub-object with one or many definition(s) of templates to deploy.

Table 3. Fields under pods and templates
Field Description

num

An integer. The number of Pods or templates to deploy.

image

A string. The docker image URL to a repository where it can be pulled.

basename

A string. One definition of the base name for the template (or pod) that you want to create.

file

A string. The path to a local file, which is either a PodSpec or template to be created.

parameters

Key-value pairs. Under parameters, you can specify a list of values to override in the pod or template.

Table 4. Fields under tuningsets
Field Description

name

A string. The name of the tuning set which will match the name specified when defining a tuning in a project.

pods

A sub-object identifying the tuningsets that will apply to Pods.

templates

A sub-object identifying the tuningsets that will apply to templates.

Table 5. Fields under tuningsets pods or tuningsets templates
Field Description

stepping

A sub-object. A stepping configuration used if you want to create an object in a step creation pattern.

rate_limit

A sub-object. A rate-limiting tuning set configuration to limit the object creation rate.

Table 6. Fields under tuningsets pods or tuningsets templates, stepping
Field Description

stepsize

An integer. How many objects to create before pausing object creation.

pause

An integer. How many seconds to pause after creating the number of objects defined in stepsize.

timeout

An integer. How many seconds to wait before failure if the object creation is not successful.

delay

An integer. How many milliseconds (ms) to wait between creation requests.

Table 7. Fields under sync
Field Description

server

A sub-object with enabled and port fields. The boolean enabled defines whether to start an HTTP server for pod synchronization. The integer port defines the HTTP server port to listen on (9090 by default).

running

A boolean. Wait for Pods with labels matching selectors to go into Running state.

succeeded

A boolean. Wait for Pods with labels matching selectors to go into Completed state.

selectors

A list of selectors to match Pods in Running or Completed states.

timeout

A string. The synchronization timeout period to wait for Pods in Running or Completed states. For values that are not 0, use units: [ns|us|ms|s|m|h].

Known issues

  • Cluster Loader fails when called without configuration. (BZ#1761925)

  • If the IDENTIFIER parameter is not defined in user templates, template creation fails with error: unknown parameter name "IDENTIFIER". If you deploy templates, add this parameter to your template to avoid this error:

    {
      "name": "IDENTIFIER",
      "description": "Number to append to the name of resources",
      "value": "1"
    }

    If you deploy Pods, adding the parameter is unnecessary.