Continuous Integration (CI) Testing


  • All CI checks must pass before a pull request can be merged.

  • The status (running and pass/fail) for all checks can be viewed by clicking the appropriate link in the checks section of a GitHub pull request.

The RAJA project uses two CI tools to run tests:

  • Azure Pipelines runs builds and tests for Linux, Windows, and MacOS environments using compilers in container images maintained in the RSE Ops Project. While we do some GPU builds on Azure, RAJA tests are only run for CPU-only builds. The current set of builds run on Azure can be seen by looking at the RAJA/azure-pipelines.yml and RAJA/Dockerfile files.

  • GitLab instance in the Collaboration Zone (CZ) of the Livermore Computing (LC) Center runs builds and tests on LC platforms using software stacks (compilers, etc.) important to many RAJA user applications. GitLab build configurations are more complex than Azure; they will be described in detail in GitLab CI.

These tools integrate with the RAJA GitHub project and automatically run RAJA builds and tests when a PR is created and when changes are pushed to a PR branch or one of our protected branches main and develop.

The following sections describe basic elements of the operation of the CI tools.

GitLab CI

The GitLab CI instance used by the RAJA project lives in the Livermore Computing (LC) Collaboration Zone (CZ). It runs builds and tests using machine and compiler environments important to RAJA user applications at LLNL.


LC security policies constrain how projects can run GitLab CI on LC platforms. Specifically, policies require that all members of a GitHub project be members of the LLNL GitHub organization and have two-factor authentication enabled on their GitHub accounts. When these requirements are satisfied, GitLab on the LC CZ can mirror a GitHub project and trigger GitLab CI when changes are made to the GitHub repo. If the requirements are not met, LC GitLab CI checks will not run. This implies, for example, that GitLab CI will not run an LLNL organization project for a PR made from a fork of the project repo by someone not in the LLNL organization.

For a compliant LLNL GitHub project like RAJA, auto-mirroring of the GitHub repo to LC GitLab is done every 30 minutes or so, triggering builds and tests on new changes pushed to the RAJA GitHub project. If you have access to LC platforms, you can learn more about LC GitLab mirroring.


GitLab CI will not run for a PR branch on a fork of the RAJA repo. The RAJA project manually manages contributions made on forks of the RAJA repo using the procedure described in Contributing to RAJA.

GitLab CI (LC) Testing Workflow

The figure below shows the sequence of steps in the RAJA GitLab CI testing process. More details about these steps will appear in the in later sections:

  1. A mirror of the RAJA GitHub repo is updated in the RAJA LC CZ GitLab project automatically (approximately every 30 minutes).


    There may be a delay in the mirroring, since it is not synchronous with changes to the RAJA GitHub project.

  2. GitLab launches CI test pipelines for any new changes made to the develop or main branches or any non-fork PR branch. While running, the execution and pass/fail status may be viewed and monitored in the GitLab CI GUI or in the RAJA GitHub project checks section of a PR.

  3. For each platform and compiler combination, Spack builds RAJA dependencies and generates a configuration in the form of a CMake cache file, or host-config file.

  4. A host-config file is passed to CMake, which configures a RAJA build space. Then, RAJA and its tests are compiled.

  5. Next, the RAJA tests are run.

  6. When test pipelines complete, results are reported to GitLab.

  7. Lastly, GitLab reports to GitHub indicating the the status of checks there.


The main steps in the RAJA GitLab CI testing workflow are shown in the figure. This process is triggered when a developer makes a PR on the GitHub project or whenever changes are pushed to the source branch of a PR.

Next, we describe the roles that external projects and files in the RAJA repo play in the RAJA GitLab CI workflow.

GitLab CI Testing Dependencies (specific to LC CZ)

RAJA GitLab CI testing depends on several other projects that we develop collaboratively with other projects. These include

  • RADIUSS Shared CI, a centralized framework for software testing with GitLab CI on LC machines. The project is developed on GitHub and is mirrored to the LC CZ GitLab instance.

  • Spack, a multi-platform package manager that builds and installs HPC software stacks.

  • Uberenv, a Python script that helps to simplify the workflow of Spack and other tools for building third-party dependencies. Uberenv is a submodule in RAJA that lives in RAJA/scripts/uberenv/.

  • RADIUSS Spack Configs, a collection of Spack compiler and package configurations used by Spack to generate build configurations. The build configurations are specific to LLNL LC platforms. Spack packages for multiple projects are maintained in this project. Shared RADIUSS CI jobs are also hosted by this project as they relate to the Spack configuration. RADIUSS Spack Configs is a submodule in RAJA that lives in RAJA/scripts/radiuss-spack-configs/.

The relationships among these dependencies in a project that uses them is described in the RADIUSS Shared CI User Guide along with information about how the framework works and how to set up a project to use it.


The RAJA Spack package is maintained in the RADIUSS Spack Configs project. After packages are updated there, they are pushed to the Spack repo on GitHub via a pull request.

The remainder of this section describes files in the RAJA repo that are used to configure and customize the shared CI framework specifically for the RAJA project.

GitLab CI Testing Files (specific to LC CZ)

The following figure shows directories and files in the RAJA project that support LC GitLab CI testing.


The figure shows directories and files in the RAJA repo that support GitLab CI testing. Files in blue are specific to the CI while those in red relates to the build (Spack) environment description. The scripts stands at the interface between CI and Spack. uberenv and radiuss-spack-configs are both Git submodules that are shared and maintained with other projects.

Briefly, these files play the following roles in GitLab CI testing:

  • The RAJA/.gitlab-ci.yml file is the top-level file for GitLab CI configuration. It defines variables used throughout the CI configuration such as GitHub project name and organization, service user account name, version information for RADIUSS Shared CI project we are using, and top-level information for triggering build-and-test sub-pipelines.

  • The RAJA/.uberenv_config.json file defines information about Spack such as Spack version we are using, location of Spack packages, etc.

  • The RAJA/.gitlab directory contains several files that connect RAJA GitLab pipelines to shared pipelines defined in the RADIUSS Shared CI project, as well as RAJA-specific jobs and global job customizations that we use, such as job time limits, etc. These files are modified from templates provided by the RADIUSS Shared CI project.

  • In particular, RAJA/.gitlab/jobs directory contains the files defining RAJA specific jobs per machine. This file is appended to the list of shared CI jobs provided by RADIUSS Spack Configs. Each job ultimately consists in one Spack spec.

  • The RAJA/scripts/gitlab/ contains commands that are run during the RAJA build and test process. It is set in the CI using the JOB_CMD variable.

In the following sections, we discuss how these files are used in the steps of the RAJA GitLab CI testing process summarized above.

Launching CI pipelines (step 2)

In step 2 of the diagram above, GitLab launches RAJA test pipelines starting with the content of the RAJA/.gitlab-ci.yml file described above. Most importantly, this file identifies the location of two files RAJA/.gitlab/subscribed-pipelines.yml and RAJA/.gitlab/custom-jobs-and-variables.yml. The subscribed-pipelines.yml file connects the RAJA GitLab environment to the platform and pipelines defined in the RADIUSS Shared CI project. The custom-jobs-and-variables.yml file defines how resources are allocated to run test jobs on various LC platforms and common build configuration variants for those platforms

Each job that is run is defined by a Spack spec in one of two places, depending on whether it is shared with other projects or it is specific to RAJA. The shared jobs are defined in files located in gitlab/radiuss-jobs/<MACHINE>.yml in the RADIUSS Spack Configs Project. Overrides (modifications) of those jobs and other RAJA-specific jobs are defined in RAJA/.gitlab/jobs/<MACHINE>.yml files.

Each shared job will be run as-is unless it is overridden in the RAJA local jobs file for the corresponding machine. For example, a shared job for the LC ruby machine may appear in the RADIUSS Spack Configs file gitlab/radiuss-jobs/ruby.yml as:

  extends: .job_on_ruby

and then may be overridden in the RAJA/.gitlab/jobs/ruby.yml file as:

    RUBY_JOB_ALLOC: "--time=60 --nodes=1"
  extends: .job_on_ruby

In this example, the Spack build spec is the same, but the job is configured with a specific timeout limit and number of nodes appropriate for RAJA testing.


A shared job override must use the same job label as the shared job defined in the RADIUSS Shared CI project.

RAJA-specific jobs whose configurations are not shared with other projects are also defined in the RAJA/.gitlab/jobs/<MACHINE>.yml files. For example:

    SPEC: " ~shared +openmp +tests +desul %clang@10.0.1 cxxflags=--gcc-toolchain=/usr/tce/packages/gcc/gcc-8.3.1 cflags=--gcc-toolchain=/usr/tce/packages/gcc/gcc-8.3.1"
  extends: .job_on_ruby

defines a RAJA job with desul atomics enabled to be run on the ruby machine.


Each base compiler configuration that is used in GitLab CI testing must have a Spack spec defined for it in the appropriate file for the machine that it will be tested on in the RADIUSS Spack Configs project.

Running a CI build and test pipeline (steps 3, 4, 5, 6)

The RAJA/scripts/gitlab/ file defines the steps executed for each build and test pipeline as well as information that will appear in the log output for each step. The script “echoes” information to the test logs indicating what it is doing. Following the echo commands in the file may help one understand the workflow.

The details of the various steps in the process may change from time to time. However, the basic sequence is:

  1. Perform some basic (platform-independent) setup.

  2. Invoke the RAJA/scripts/uberenv/ Python script that drives Spack to generate a host-config file from a given spec (step 3).

  3. Run CMake to configure a build space passing the host-config file to it which contains all CMake variable settings for the configuration.

  4. Build RAJA and tests (step 4).

  5. Run RAJA tests via ctest (step 5).

  6. Export XML test reports for reporting in GitLab (step 6), which is done by the RADIUSS Shared CI Framework.

  7. Perform clean up tasks.

Recall that RAJA project specific settings defining the Spack version to use, locations of Spack packages, etc. are located in the RAJA/.uberenv_config.json file.

Also, recall that to generate a host-config file, Spack uses packages and specs in the RADIUSS Spack Configs project (a RAJA submodule), plus RAJA-specific specs defined in files in the RAJA/.gitlab/jobs directory, as described earlier.

Azure Pipelines CI

We use Azure Pipelines to run builds and tests for Linux, Windows, and MacOS environments. While we do builds for CUDA, HIP, and SYCL RAJA GPU back-ends in the Azure Linux environment, RAJA tests are only run for CPU-only pipelines.

Azure Pipelines Testing Workflow

The Azure Pipelines testing workflow for RAJA is much simpler than the GitLab testing process described earlier.

The test jobs we run for each OS environment are specified in the RAJA/azure-pipelines.yml file. This file defines the job steps, commands, compilers, etc. for each OS environment in the associated - job: section. A summary of the configurations we build are:

  • Windows. The - job: Windows Windows section contains information for the Windows test builds. For example, we build and test RAJA as a static and shared library. This is indicated in the Windows strategy section:


    We use the Windows/compiler image provided by the Azure application indicated the pool section; for example:

      vmImage: 'windows-2019'

    MacOS. The - job: Mac section contains information for Mac test builds. For example, we build RAJA using the the MacOS/compiler image provided by the Azure application indicated in the pool section; for example:

      vmImage: 'macOS-latest'

    Linux. The - job: Docker section contains information for Linux test builds. We build and test RAJA using Docker container images generated with recent versions of various compilers. The RAJA project shares these images with other open-source LLNL RADIUSS projects and they are maintained in the RES-Ops Docker project on GitHub. The builds we do at any point in time are located in the strategy block:

          docker_target: ...
          docker_target: ...
          docker_target: ...

    The Linux OS the docker images are run on is indicated in the pool section; for example:

      vmImage: 'ubuntu-latest'

Docker Builds

For each Linux/Docker pipeline, the base container images, CMake, build, and test commands are located in RAJA/Dockerfile.

The base container images are built and maintained through the RSE-Ops Docker project. A table of the most up-to-date containers can be found here. These images are rebuilt regularly ensuring that we have the most up to date builds of each container and compiler.


Please see Reproducing Docker Builds Locally for more information about reproducing Docker builds locally for debugging purposes.