What Cluster Loader Does

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 Origin deployment at various cluster states.

Installing Cluster Loader

Cluster Loader is included in the atomic-openshift-tests package. To install it, run:

$ yum install atomic-openshift-tests

After installation, the test executable extended.test is located in /usr/libexec/atomic-openshift/extended.test.

Running Cluster Loader

  1. Set the KUBECONFIG variable to the location of the administrator kubeconfig:

    $ export KUBECONFIG=${KUBECONFIG-$HOME/.kube/config}
  2. Execute Cluster Loader using the built-in test configuration, which deploys five template builds and waits for them to complete:

    $ cd /usr/libexec/atomic-openshift/
    ./extended.test --ginkgo.focus="Load cluster"

    Alternatively, execute Cluster Loader with a user-defined configuration by adding the flag for --viper-config:

    $ ./extended.test --ginkgo.focus="Load cluster" --viper-config=config/test (1)
    1 In this example, there is a subdirectory called config/ with a configuration file called test.yml. In the command line, exclude the extension of the configuration file, as the tool will automatically determine the file type and extension.

Configuring Cluster Loader

Create multiple namespaces (projects), which contain multiple templates or pods.

Locate the configuration files for Cluster Loader in the config/ subdirectory. The pod files and template files referenced in these configuration examples are found in the content/ subdirectory.

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 will delete 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.

tuningSet

A sub-object with one definition per configuration. TuningSet allows the user to define a tuning set to add configurable timing to project or object creation (pods, templates, etc).

Table 2. Fields under projects
Field Description

number

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.

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

total

This field is not used.

number

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 tuningset
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 tuningset that will apply to pods.

templates

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

Table 5. Fields under tuningset pods or tuningset 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 tuningset pods or tuningset 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

Example Cluster Loader Configuration File

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

provider: local
ClusterLoader:
  cleanup: true
  projects:
    - num: 1
      basename: clusterloader-cakephp-mysql
      tuning: default
      templates:
        - num: 1
          file: ./examples/quickstarts/cakephp-mysql.json

    - num: 1
      basename: clusterloader-dancer-mysql
      tuning: default
      templates:
        - num: 1
          file: ./examples/quickstarts/dancer-mysql.json

    - num: 1
      basename: clusterloader-django-postgresql
      tuning: default
      templates:
        - num: 1
          file: ./examples/quickstarts/django-postgresql.json

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

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

  tuningset: (1)
    - name: default
      pods:
        stepping: (2)
          stepsize: 5
          pause: 0 s
        rate_limit: (3)
          delay: 0 ms
1 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.
2 Stepping will pause for M seconds after each N objects are created.
3 Rate limiting will wait M milliseconds between the creation of objects.