Explaining the first job in detail

Download / view the complete first job YAML.

As the first job, this is a simple emulated test which does not need any extra hardware, it does not use protocols and runs as a single job. The elements of the first job are described in detail below.

Note

This kind of test is generally termed singlenode.

Top level elements of a test job

  • comments - One of the reasons why V2 uses YAML for job submission is because YAML supports comments. Please use comments liberally. Comments are preserved in the job definition which can be viewed and downloaded from the instance. Comments are not passed to the dispatcher.

  • device_type - a label which must match the type of device declared on the instance to which you want to submit this job. Each device type can have one or more devices available. In this case, qemu.

  • job_name - your own free text name for this job. This name is used in the server side tables but has no further relevance for the dispatcher. There is no need to make this into a single long word, any valid YAML string is allowed, so commas, capitalisation and whitespace are fine. Long job names, in particular, need to include whitespace. Avoid the temptation to use a build URL as the job name, use Metadata instead.

  • timeouts - a range of things can go wrong inside a LAVA test job, so the test writer needs to indicate how long parts of the job should take. This allows LAVA to fail jobs which have hung and return the device to scheduling for the next test job. Timeouts at the top level include the job, the default timeout per action and can include the default timeout for the device to respond using a connection.

    See also

    Timeouts

  • priority - supports values if high, medium or low. The scheduler considers the job priority when ordering the queue to consider which job should run next. Do not abuse priority.

  • visibility - supports values of public, personal and group and controls who is allowed to view the job and the results generated by the job. This includes whether the results are available to queries and to charts.

  • context - Not all testjobs will use a job context, it is available to override some of the server-side device configuration templates. In this case, arch: amd64 sets the template to use the qemu-system-x86_64 executable when starting the emulation.

  • metadata - Once the test job becomes part of an automated submission or a CI loop, metadata needs to be used to identify each submission, provide information on exactly what changed from the last test job and information on how other users can modify the test job artifacts to extend or debug the results.

General details of the test job are specified in the top level elements, such as in this snippet from the first job:

device_type: qemu
job_name: QEMU pipeline, first job

timeouts:
  job:
    minutes: 15
  action:
    minutes: 5
  connection:
    minutes: 2
priority: medium
visibility: public

Actions within the test job

Each test job needs a list of actions, comprising of deploy, boot and test.

  • deploy - download files required to boot the device and prepare an overlay of files to run in the test action.
  • boot - specify the method to boot the device and the prompts which will dictate whether the device is considered to have been booted correctly.
  • test - specify the repositories to clone which will provide the scripts which will run the test you want to execute for this job.

Deploy action for QEMU

Deployment methods are identified by the to parameter, for QEMU the supported deployment method is to tmpfs. The image to deploy is specified as an image dictionary which supports the formatting of the options to QEMU and the compression algorithm to use to decompress the download prior to passing to QEMU.

Arguments to QEMU need to include the filename, often embedded within a specific option string. To achieve this, LAVA supports a label for the image which will be substituted into the option.

actions:
- deploy:
    timeout:
      minutes: 5
    to: tmpfs
    images:
      rootfs:
        image_arg: -drive format=raw,file={rootfs}
        url: https://images.validation.linaro.org/kvm/standard/stretch-2.img.gz
        compression: gz
    os: debian

The other role of a deploy action is to prepare the overlay which will contain the test shell scripts and repositories. These will be added to the booted image and then executed automatically, generating the results for the test job.

Certain aspects of executing tests on a booted device require knowledge about which OS will be running after the device has booted. This is particularly relevant when the test scripts may require additional dependencies to be installed in the running system. The test scripts need to know whether to use apt or yum or something else to do the installation work. Some other OS deployments may change other elements within the test, so the test job submission will fail if the os parameter is not set or is set to an unrecognised string.

Supported operating systems include debian, ubuntu, oe (for OpenEmbedded) and fedora.

Example of deploy label substitution

https://images.validation.linaro.org/kvm/standard/stretch-2.img.gz is downloaded and then decompressed using the gz algorithm to create a file called stretch-2.img in a tmpfs location. This location is then substituted into the image_arg:

-drive format=raw,file=/tmp/tmp.23FDsf/stretch-2.img

Boot action for QEMU

One of the primary roles of the boot action parameters is to ensure that the correct pipeline is constructed for this test job. The specified method is used to match against the available boot methods. In this case, the boot method is to call QEMU. The qemu boot method also needs the media parameter set to tmpfs to distinguish this from other boot methods. The first job uses a test shell and needs to specify the list of prompts which LAVA can recognise to start the operation of the test shell.

    timeout:
      minutes: 2
    method: qemu
    media: tmpfs
    prompts: ["root@debian:"]
    auto_login:
      login_prompt: "login:"
      username: root

Note

prompts - it is essential that the test writer records the information on what prompt will be presented when the system boots into that image successfully. If this information is not available from the location from which you downloaded the image, you will need to ask for that information or boot the image yourself and identify the prompt.

Test action for QEMU

The test action block in the first job contains two sets of definition parameters, each consisting of:

  • repository - the URL to pass to git or bzr to clone the repository
  • from - the method of obtaining the repository.
  • path - the YAML file inside the repository which contains the Lava Test Shell Definition to be used for this test.
  • name - the name to use when executing this test.

The test action block in the first job also includes a timeout as an example of how to specify a timeout for a particular section of the job.

- test:
    timeout:
      minutes: 5
    definitions:
    - repository: git://git.linaro.org/qa/test-definitions.git
      from: git
      path: ubuntu/smoke-tests-basic.yaml
      name: smoke-tests
    - repository: https://git.linaro.org/lava-team/lava-functional-tests.git
      from: git
      path: lava-test-shell/single-node/singlenode03.yaml
      name: singlenode-advanced

See also

Back to your first job Job Submission.