Configuring runners

Tier: Free, Premium, Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

This document describes how to configure runners in the GitLab UI.

If you need to configure runners on the machine where you installed GitLab Runner, see the GitLab Runner documentation.

Set the maximum job timeout

You can specify a maximum job timeout for each runner to prevent projects with longer job timeouts from using the runner. The maximum job timeout is used if it is shorter than the job timeout defined in the project.

To set a runner’s maximum timeout, set the maximum_timeout parameter in the REST API endpoint PUT /runners/:id.

For an instance runner

Prerequisites:

  • You must be an administrator.

You can override the job timeout for instance runners on self-managed GitLab installations only.

On GitLab.com, you cannot override the job timeout for GitLab hosted instance runners and must use the project defined timeout instead.

To set the maximum job timeout:

  1. On the left sidebar, at the bottom, select Admin.
  2. Select CI/CD > Runners.
  3. To the right of the runner, you want to edit, select Edit ().
  4. In the Maximum job timeout field, enter a value in seconds. The minimum value is 600 seconds (10 minutes).
  5. Select Save changes.

For a group runner

Prerequisites:

  • You must have the Owner role for the group.

To set the maximum job timeout:

  1. On the left sidebar, select Search or go to and find your group.
  2. Select Build > Runners.
  3. To the right of the runner you want to edit, select Edit ().
  4. In the Maximum job timeout field, enter a value in seconds. The minimum value is 600 seconds (10 minutes).
  5. Select Save changes.

For a project runner

Prerequisites:

  • You must have the Owner role for the project.

To set the maximum job timeout:

  1. On the left sidebar, select Search or go to and find your project.
  2. Select Settings > CI/CD.
  3. Expand Runners.
  4. To the right of the runner you want to edit, select Edit ().
  5. In the Maximum job timeout field, enter a value in seconds. The minimum value is 600 seconds (10 minutes). If not defined, the job timeout for the project is used instead.
  6. Select Save changes.

How maximum job timeout works

Example 1 - Runner timeout bigger than project timeout

  1. You set the maximum job timeout for a runner to 24 hours.
  2. You set the CI/CD Timeout for a project to 2 hours.
  3. You start a job.
  4. The job, if running longer, times out after 2 hours.

Example 2 - Runner timeout not configured

  1. You remove the maximum job timeout configuration from a runner.
  2. You set the CI/CD Timeout for a project to 2 hours.
  3. You start a job.
  4. The job, if running longer, times out after 2 hours.

Example 3 - Runner timeout smaller than project timeout

  1. You set the maximum job timeout for a runner to 30 minutes.
  2. You set the CI/CD Timeout for a project to 2 hours.
  3. You start a job.
  4. The job, if running longer, times out after 30 minutes.

Set script and after_script timeouts

History

To control the amount of time script and after_script runs before it terminates, specify a timeout value in the .gitlab-ci.yml file.

For example, you can specify a timeout to terminate a long-running script early, so that artifacts and caches can still be uploaded before the job timeout is exceeded.

  • To set a timeout for script, use the job variable RUNNER_SCRIPT_TIMEOUT.
  • To set a timeout for after_script, and override the default of 5 minutes, use the job variable RUNNER_AFTER_SCRIPT_TIMEOUT.

Both of these variables accept Go’s duration format (for example, 40s, 1h20m, 2h 4h30m30s).

For example: 

job-with-script-timeouts:
  variables:
    RUNNER_SCRIPT_TIMEOUT: 15m
    RUNNER_AFTER_SCRIPT_TIMEOUT: 10m
  script:
    - "I am allowed to run for min(15m, remaining job timeout)."
  after_script:
    - "I am allowed to run for min(10m, remaining job timeout)."

job-artifact-upload-on-timeout:
  timeout: 1h                           # set job timeout to 1 hour
  variables:
     RUNNER_SCRIPT_TIMEOUT: 50m         # only allow script to run for 50 minutes
  script:
    - long-running-process > output.txt # will be terminated after 50m

  artifacts: # artifacts will have roughly ~10m to upload
    paths:
      - output.txt
    when: on_failure # on_failure because script termination after a timeout is treated as a failure

Protecting sensitive information

The security risks are greater when using instance runners as they are available by default to all groups and projects in a GitLab instance. Depending on the runner executor used and the file system, the code that the runner executes and the runner authentication token might get exposed to all users who have access to the runner host environment. For example, users with access to the runner authentication token can use it to create a clone of a runner and submit false jobs in a vector attack. For more information, see Security Considerations.

Configuring long polling

To reduce job queueing times and load on your GitLab server, configure long polling.

Using instance runners in forked projects

When a project is forked, the job settings related to jobs are copied. If you have instance runners configured for a project and a user forks that project, the instance runners serve jobs of this project.

Due to a known issue, if the runner settings of the forked project does not match the new project namespace, the following message displays: An error occurred while forking the project. Please try again..

To work around this issue, ensure that the instance runner settings are consistent in the forked project and the new namespace.

  • If instance runners are enabled on the forked project, then this should also be enabled on the new namespace.
  • If instance runners are disabled on the forked project, then this should also be disabled on the new namespace.

Reset the runner registration token for a project (deprecated)

caution
The ability to pass a runner registration token, and support for certain configuration arguments was deprecated in GitLab 15.6 and will be removed in GitLab 18.0. Authentication tokens should be used instead. For more information, see Migrating to the new runner registration workflow.

If you think that a registration token for a project was revealed, you should reset it. A registration token can be used to register another runner for the project. That new runner may then be used to obtain the values of secret variables or to clone project code.

To reset the registration token:

  1. On the left sidebar, select Search or go to and find your project.
  2. Select Settings > CI/CD.
  3. Expand Runners.
  4. To the right of New project runner, select the vertical ellipsis ().
  5. Select Reset registration token.
  6. Select Reset token.

After you reset the registration token, it is no longer valid and does not register any new runners to the project. You should also update the registration token in tools you use to provision and register new values.

Authentication token security

History

Each runner uses a runner authentication token to connect to and authenticate with a GitLab instance.

To help prevent the token from being compromised, you can have the token rotate automatically at specified intervals. When the tokens are rotated, they are updated for each runner, regardless of the runner’s status (online or offline).

No manual intervention should be required, and no running jobs should be affected. For more information about token rotation, see Runner authentication token does not update when rotated.

If you need to manually update the runner authentication token, you can run a command to reset the token.

Reset the runner configuration authentication token

If a runner’s authentication token is exposed, an attacker could use it to clone the runner.

To reset the runner configuration authentication token:

  1. Delete the runner:
  2. Create a new runner so that it is assigned a new runner authentication token:
  3. Optional. To verify that the previous runner authentication token has been revoked, use the Runners API.

Automatically rotate runner authentication tokens

You can specify an interval to rotate runner authentication tokens. Regularly rotating runner authentication tokens helps minimize the risk of unauthorized access to your GitLab instance through compromised tokens.

Prerequisites:

To automatically rotate runner authentication tokens:

  1. On the left sidebar, at the bottom, select Admin.
  2. Select Settings > CI/CD.
  3. Expand Continuous Integration and Deployment.
  4. Set a Runners expiration time for runners, leave empty for no expiration.
  5. Select Save changes.

Before the interval expires, runners automatically request a new runner authentication token. For more information about token rotation, see Runner authentication token does not update when rotated.

Prevent runners from revealing sensitive information

To ensure runners don’t reveal sensitive information, you can configure them to only run jobs on protected branches, or jobs that have protected tags.

Runners configured to run jobs on protected branches cannot run jobs in merge request pipelines.

For an instance runner

Prerequisites:

  • You must be an administrator.
  1. On the left sidebar, at the bottom, select Admin.
  2. Select CI/CD > Runners.
  3. To the right of the runner you want to protect, select Edit ().
  4. Select the Protected checkbox.
  5. Select Save changes.

For a group runner

Prerequisites:

  • You must have the Owner role for the group.
  1. On the left sidebar, select Search or go to and find your group.
  2. Select Build > Runners.
  3. To the right of the runner you want to protect, select Edit ().
  4. Select the Protected checkbox.
  5. Select Save changes.

For a project runner

Prerequisites:

  • You must have the Owner role for the project.
  1. On the left sidebar, select Search or go to and find your project.
  2. Select Settings > CI/CD.
  3. Expand Runners.
  4. To the right of the runner you want to protect, select Edit ().
  5. Select the Protected checkbox.
  6. Select Save changes.

Control jobs that a runner can run

You can use tags to control the jobs a runner can run. For example, you can specify the rails tag for runners that have the dependencies to run Rails test suites.

GitLab CI/CD tags are different to Git tags. GitLab CI/CD tags are associated with runners. Git tags are associated with commits.

For an instance runner

Prerequisites:

  • You must be an administrator.

To control the jobs that an instance runner can run:

  1. On the left sidebar, at the bottom, select Admin.
  2. Select CI/CD > Runners.
  3. To the right of the runner you want to edit, select Edit ().
  4. Set the runner to run tagged or untagged jobs:
    • To run tagged jobs, in the Tags field, enter the job tags separated with a comma. For example, macos, rails.
    • To run untagged jobs, select the Run untagged jobs checkbox.
  5. Select Save changes.

For a group runner

Prerequisites:

  • You must have the Owner role for the group.

To control the jobs that a group runner can run:

  1. On the left sidebar, select Search or go to and find your group.
  2. Select Build > Runners.
  3. To the right of the runner you want to edit, select Edit ().
  4. Set the runner to run tagged or untagged jobs:
    • To run tagged jobs, in the Tags field, enter the job tags separated with a comma. For example, macos, ruby.
    • To run untagged jobs, select the Run untagged jobs checkbox.
  5. Select Save changes.

For a project runner

Prerequisites:

  • You must have the Owner role for the project.

To control the jobs that a project runner can run:

  1. On the left sidebar, select Search or go to and find your project.
  2. Select Settings > CI/CD.
  3. Expand Runners.
  4. To the right of the runner you want to edit, select Edit ().
  5. Set the runner to run tagged or untagged jobs:
    • To run tagged jobs, in the Tags field, enter the job tags separated with a comma. For example, macos, ruby.
    • To run untagged jobs, select the Run untagged jobs checkbox.
  6. Select Save changes.

How the runner uses tags

Runner runs only tagged jobs

The following examples illustrate the potential impact of the runner being set to run only tagged jobs.

Example 1:

  1. The runner is configured to run only tagged jobs and has the docker tag.
  2. A job that has a hello tag is executed and stuck.

Example 2:

  1. The runner is configured to run only tagged jobs and has the docker tag.
  2. A job that has a docker tag is executed and run.

Example 3:

  1. The runner is configured to run only tagged jobs and has the docker tag.
  2. A job that has no tags defined is executed and stuck.

Runner is allowed to run untagged jobs

The following examples illustrate the potential impact of the runner being set to run tagged and untagged jobs.

Example 1:

  1. The runner is configured to run untagged jobs and has the docker tag.
  2. A job that has no tags defined is executed and run.
  3. A second job that has a docker tag defined is executed and run.

Example 2:

  1. The runner is configured to run untagged jobs and has no tags defined.
  2. A job that has no tags defined is executed and run.
  3. A second job that has a docker tag defined is stuck.

A runner and a job have multiple tags

The selection logic that matches the job and runner is based on the list of tags defined in the job.

The following examples illustrate the impact of a runner and a job having multiple tags. For a runner to be selected to run a job, it must have all of the tags defined in the job script block.

Example 1:

  1. The runner is configured with the tags [docker, shell, gpu].
  2. The job has the tags [docker, shell, gpu] and is executed and run.

Example 2:

  1. The runner is configured with the tags [docker, shell, gpu].
  2. The job has the tags [docker, shell,] and is executed and run.

Example 3:

  1. The runner is configured with the tags [docker, shell].
  2. The job has the tags [docker, shell, gpu] and is not executed.

Use tags to run jobs on different platforms

You can use tags to run different jobs on different platforms. For example, if you have an OS X runner with tag osx and a Windows runner with tag windows, you can run a job on each platform.

Update the tags field in the .gitlab-ci.yml: 

windows job:
  stage: build
  tags:
    - windows
  script:
    - echo Hello, %USERNAME%!

osx job:
  stage: build
  tags:
    - osx
  script:
    - echo "Hello, $USER!"

Use CI/CD variables in tags

In the .gitlab-ci.yml file, use CI/CD variables with tags for dynamic runner selection: 

variables:
  KUBERNETES_RUNNER: kubernetes

  job:
    tags:
      - docker
      - $KUBERNETES_RUNNER
    script:
      - echo "Hello runner selector feature"

Configure runner behavior with variables

You can use CI/CD variables to configure runner Git behavior globally or for individual jobs:

You can also use variables to configure how many times a runner attempts certain stages of job execution.

When using the Kubernetes executor, you can use variables to override Kubernetes CPU and memory allocations for requests and limits.

Git strategy

The GIT_STRATEGY variable configures how the build directory is prepared and repository content is fetched. You can set this variable globally or per job in the variables section. 

variables:
  GIT_STRATEGY: clone

Possible values are clone, fetch, none, and empty. If you do not specify a value, jobs use the project’s pipeline setting.

clone is the slowest option. It clones the repository from scratch for every job, ensuring that the local working copy is always pristine. If an existing worktree is found, it is removed before cloning.

fetch is faster as it re-uses the local working copy (falling back to clone if it does not exist). git clean is used to undo any changes made by the last job, and git fetch is used to retrieve commits made after the last job ran.

However, fetch does require access to the previous worktree. This works well when using the shell or docker executor because these try to preserve worktrees and try to re-use them by default.

This has limitations when using the Docker Machine executor.

A Git strategy of none also re-uses the local working copy, but skips all Git operations usually done by GitLab. GitLab Runner pre-clone scripts are also skipped, if present. This strategy could mean you need to add fetch and checkout commands to your .gitlab-ci.yml script.

It can be used for jobs that operate exclusively on artifacts, like a deployment job. Git repository data may be present, but it’s likely out of date. You should only rely on files brought into the local working copy from cache or artifacts, and be aware that cache and artifact files from previous pipelines might still be present.

Unlike none, the empty Git strategy deletes and then re-creates a dedicated build directory before downloading cache or artifact files. With this strategy, the GitLab Runner hook scripts are still run (if provided) to allow for further behavior customization. Use the empty Git strategy when:

  • You do not need the repository data to be present.
  • You want a clean, controlled, or customized starting state every time a job runs.

Git submodule strategy

The GIT_SUBMODULE_STRATEGY variable is used to control if / how Git submodules are included when fetching the code before a build. You can set them globally or per-job in the variables section.

There are three possible values: none, normal, and recursive:

  • none means that submodules are not included when fetching the project code. This is the default, which matches the pre-v1.10 behavior.

  • normal means that only the top-level submodules are included. It’s equivalent to: 

    git submodule sync
git submodule update --init

  • recursive means that all submodules (including submodules of submodules) are included. This feature needs Git v1.8.1 and later. When using a GitLab Runner with an executor not based on Docker, make sure the Git version meets that requirement. It’s equivalent to: 

    git submodule sync --recursive
git submodule update --init --recursive

For this feature to work correctly, the submodules must be configured (in .gitmodules) with either:

  • the HTTP(S) URL of a publicly-accessible repository, or
  • a relative path to another repository on the same GitLab server. See the Git submodules documentation.

You can provide additional flags to control advanced behavior using GIT_SUBMODULE_UPDATE_FLAGS.

Git checkout

The GIT_CHECKOUT variable can be used when the GIT_STRATEGY is set to either clone or fetch to specify whether a git checkout should be run. If not specified, it defaults to true. You can set them globally or per-job in the variables section.

If set to false, the runner:

  • when doing fetch - updates the repository and leaves the working copy on the current revision,
  • when doing clone - clones the repository and leaves the working copy on the default branch.

If GIT_CHECKOUT is set to true, both clone and fetch work the same way. The runner checks out the working copy of a revision related to the CI pipeline: 

variables:
  GIT_STRATEGY: clone
  GIT_CHECKOUT: "false"
script:
  - git checkout -B master origin/master
  - git merge $CI_COMMIT_SHA

Git clean flags

The GIT_CLEAN_FLAGS variable is used to control the default behavior of git clean after checking out the sources. You can set it globally or per-job in the variables section.

GIT_CLEAN_FLAGS accepts all possible options of the git clean command.

git clean is disabled if GIT_CHECKOUT: "false" is specified.

If GIT_CLEAN_FLAGS is:

  • Not specified, git clean flags default to -ffdx.
  • Given the value none, git clean is not executed.

For example: 

variables:
  GIT_CLEAN_FLAGS: -ffdx -e cache/
script:
  - ls -al cache/

Git fetch extra flags

Use the GIT_FETCH_EXTRA_FLAGS variable to control the behavior of git fetch. You can set it globally or per-job in the variables section.

GIT_FETCH_EXTRA_FLAGS accepts all options of the git fetch command. However, GIT_FETCH_EXTRA_FLAGS flags are appended after the default flags that can’t be modified.

The default flags are:

If GIT_FETCH_EXTRA_FLAGS is:

  • Not specified, git fetch flags default to --prune --quiet along with the default flags.
  • Given the value none, git fetch is executed only with the default flags.

For example, the default flags are --prune --quiet, so you can make git fetch more verbose by overriding this with just --prune: 

variables:
  GIT_FETCH_EXTRA_FLAGS: --prune
script:
  - ls -al cache/

The configuration above results in git fetch being called this way: 

git fetch origin $REFSPECS --depth 50  --prune

Where $REFSPECS is a value provided to the runner internally by GitLab.

Sync or exclude specific submodules from CI jobs

History

Use the GIT_SUBMODULE_PATHS variable to control which submodules have to be synced or updated. You can set it globally or per-job in the variables section.

The path syntax is the same as git submodule:

  • To sync and update specific paths: 

    variables:
   GIT_SUBMODULE_PATHS: submoduleA submoduleB

  • To exclude specific paths: 

    variables:
   GIT_SUBMODULE_PATHS: :(exclude)submoduleA :(exclude)submoduleB
caution
Git ignores nested paths. To ignore a nested submodule, exclude the parent submodule and then manually clone it in the job’s scripts. For example, git clone <repo> --recurse-submodules=':(exclude)nested-submodule'. Make sure to wrap the string in single quotes so the YAML can be parsed successfully.

Git submodule update flags

Use the GIT_SUBMODULE_UPDATE_FLAGS variable to control the behavior of git submodule update when GIT_SUBMODULE_STRATEGY is set to either normal or recursive. You can set it globally or per-job in the variables section.

GIT_SUBMODULE_UPDATE_FLAGS accepts all options of the git submodule update subcommand. However, GIT_SUBMODULE_UPDATE_FLAGS flags are appended after a few default flags:

Git honors the last occurrence of a flag in the list of arguments, so manually providing them in GIT_SUBMODULE_UPDATE_FLAGS overrides these default flags.

You can use this variable to fetch the latest remote HEAD instead of the commit tracked, in the repository, or to speed up the checkout by fetching submodules in multiple parallel jobs: 

variables:
  GIT_SUBMODULE_STRATEGY: recursive
  GIT_SUBMODULE_UPDATE_FLAGS: --remote --jobs 4
script:
  - ls -al .git/modules/

The configuration above results in git submodule update being called this way: 

git submodule update --init --depth 50 --recursive --remote --jobs 4
caution
You should be aware of the implications for the security, stability, and reproducibility of your builds when using the --remote flag. In most cases, it is better to explicitly track submodule commits as designed, and update them using an auto-remediation/dependency bot.

Rewrite submodule URLs to HTTPS

History

Use the GIT_SUBMODULE_FORCE_HTTPS variable to force a rewrite of all Git and SSH submodule URLs to HTTPS. This allows you to clone submodules on the same GitLab instance that use absolute URLs, even if they were configured with a Git or SSH protocol. 

variables:
  GIT_SUBMODULE_STRATEGY: recursive
  GIT_SUBMODULE_FORCE_HTTPS: "true"

When enabled, GitLab Runner uses a CI/CD job token to clone the submodules with the permissions of the user executing the job, and does not require SSH credentials.

Shallow cloning

You can specify the depth of fetching and cloning using GIT_DEPTH. GIT_DEPTH does a shallow clone of the repository and can significantly speed up cloning. It can be helpful for repositories with a large number of commits or old, large binaries. The value is passed to git fetch and git clone.

Newly-created projects automatically have a default git depth value of 50.

If you use a depth of 1 and have a queue of jobs or retry jobs, jobs may fail.

Git fetching and cloning is based on a ref, such as a branch name, so runners can’t clone a specific commit SHA. If multiple jobs are in the queue, or you’re retrying an old job, the commit to be tested must be within the Git history that is cloned. Setting too small a value for GIT_DEPTH can make it impossible to run these old commits and unresolved reference is displayed in job logs. You should then reconsider changing GIT_DEPTH to a higher value.

Jobs that rely on git describe may not work correctly when GIT_DEPTH is set since only part of the Git history is present.

To fetch or clone only the last 3 commits: 

variables:
  GIT_DEPTH: "3"

You can set it globally or per-job in the variables section.

Git submodule depth

History

Use the GIT_SUBMODULE_DEPTH variable to specify the depth of fetching and cloning submodules when GIT_SUBMODULE_STRATEGY is set to either normal or recursive. You can set it globally or for a specific job in the variables section.

When you set the GIT_SUBMODULE_DEPTH variable, it overwrites the GIT_DEPTH setting for the submodules only.

To fetch or clone only the last 3 commits: 

variables:
  GIT_SUBMODULE_DEPTH: 3

Custom build directories

By default, GitLab Runner clones the repository in a unique subpath of the $CI_BUILDS_DIR directory. However, your project might require the code in a specific directory (Go projects, for example). In that case, you can specify the GIT_CLONE_PATH variable to tell the runner the directory to clone the repository in: 

variables:
  GIT_CLONE_PATH: $CI_BUILDS_DIR/project-name

test:
  script:
    - pwd

The GIT_CLONE_PATH must always be within $CI_BUILDS_DIR. The directory set in $CI_BUILDS_DIR is dependent on executor and configuration of runners.builds_dir setting.

This can only be used when custom_build_dir is enabled in the runner’s configuration.

Handling concurrency

An executor that uses a concurrency greater than 1 might lead to failures. Multiple jobs might be working on the same directory if the builds_dir is shared between jobs.

The runner does not try to prevent this situation. It’s up to the administrator and developers to comply with the requirements of runner configuration.

To avoid this scenario, you can use a unique path within $CI_BUILDS_DIR, because runner exposes two additional variables that provide a unique ID of concurrency:

  • $CI_CONCURRENT_ID: Unique ID for all jobs running within the given executor.
  • $CI_CONCURRENT_PROJECT_ID: Unique ID for all jobs running within the given executor and project.

The most stable configuration that should work well in any scenario and on any executor is to use $CI_CONCURRENT_ID in the GIT_CLONE_PATH. For example: 

variables:
  GIT_CLONE_PATH: $CI_BUILDS_DIR/$CI_CONCURRENT_ID/project-name

test:
  script:
    - pwd -P

The $CI_CONCURRENT_PROJECT_ID should be used in conjunction with $CI_PROJECT_PATH as the $CI_PROJECT_PATH provides a path of a repository. That is, group/subgroup/project. For example: 

variables:
  GIT_CLONE_PATH: $CI_BUILDS_DIR/$CI_CONCURRENT_ID/$CI_PROJECT_PATH

test:
  script:
    - pwd -P

Nested paths

The value of GIT_CLONE_PATH is expanded once and nesting variables within is not supported.

For example, you define both the variables below in your .gitlab-ci.yml file: 

variables:
  GOPATH: $CI_BUILDS_DIR/go
  GIT_CLONE_PATH: $GOPATH/src/namespace/project

The value of GIT_CLONE_PATH is expanded once into $CI_BUILDS_DIR/go/src/namespace/project, and results in failure because $CI_BUILDS_DIR is not expanded.

Ignore errors in after_script

You can use after_script in a job to define an array of commands that should run after the job’s before_script and script sections. The after_script commands run regardless of the script termination status (failure or success).

By default, GitLab Runner ignores any errors that happen when after_script runs. To set the job to fail immediately on errors when after_script runs, set the AFTER_SCRIPT_IGNORE_ERRORS CI/CD variable to false. For example: 

variables:
  AFTER_SCRIPT_IGNORE_ERRORS: false

Job stages attempts

You can set the number of attempts that the running job tries to execute the following stages:

Variable Description
ARTIFACT_DOWNLOAD_ATTEMPTS Number of attempts to download artifacts running a job
EXECUTOR_JOB_SECTION_ATTEMPTS The number of attempts to run a section in a job after a No Such Container error (Docker executor only).
GET_SOURCES_ATTEMPTS Number of attempts to fetch sources running a job
RESTORE_CACHE_ATTEMPTS Number of attempts to restore the cache running a job

The default is one single attempt.

Example: 

variables:
  GET_SOURCES_ATTEMPTS: 3

You can set them globally or per-job in the variables section.

System calls not available on GitLab.com instance runners

GitLab.com instance runners run on CoreOS. This means that you cannot use some system calls, like getlogin, from the C standard library.

Artifact and cache settings

Artifact and cache settings control the compression ratio of artifacts and caches. Use these settings to specify the size of the archive produced by a job.

  • On a slow network, uploads might be faster for smaller archives.
  • On a fast network where bandwidth and storage are not a concern, uploads might be faster using the fastest compression ratio, despite the archive produced being larger.

For GitLab Pages to serve HTTP Range requests, artifacts should use the ARTIFACT_COMPRESSION_LEVEL: fastest setting, as only uncompressed zip archives support this feature.

A meter can be enabled to provide the rate of transfer for uploads and downloads.

You can set a maximum time for cache upload and download with the CACHE_REQUEST_TIMEOUT setting. This setting can be useful when slow cache uploads substantially increase the duration of your job. 

variables:
  # output upload and download progress every 2 seconds
  TRANSFER_METER_FREQUENCY: "2s"

  # Use fast compression for artifacts, resulting in larger archives
  ARTIFACT_COMPRESSION_LEVEL: "fast"

  # Use no compression for caches
  CACHE_COMPRESSION_LEVEL: "fastest"

  # Set maximum duration of cache upload and download
  CACHE_REQUEST_TIMEOUT: 5
Variable Description
TRANSFER_METER_FREQUENCY Specify how often to print the meter’s transfer rate. It can be set to a duration (for example, 1s or 1m30s). A duration of 0 disables the meter (default). When a value is set, the pipeline shows a progress meter for artifact and cache uploads and downloads.
ARTIFACT_COMPRESSION_LEVEL To adjust compression ratio, set to fastest, fast, default, slow, or slowest. This setting works with the Fastzip archiver only, so the GitLab Runner feature flag FF_USE_FASTZIP must also be enabled.
CACHE_COMPRESSION_LEVEL To adjust compression ratio, set to fastest, fast, default, slow, or slowest. This setting works with the Fastzip archiver only, so the GitLab Runner feature flag FF_USE_FASTZIP must also be enabled.
CACHE_REQUEST_TIMEOUT Configure the maximum duration of cache upload and download operations for a single job in minutes. Default is 10 minutes.

Artifact provenance metadata

History

Runners can generate and produce provenance metadata for all build artifacts.

To enable artifact provenance data, set the RUNNER_GENERATE_ARTIFACTS_METADATA environment variable to true. You can set the variable as global or for individual jobs: 

variables:
  RUNNER_GENERATE_ARTIFACTS_METADATA: "true"

job1:
  variables:
    RUNNER_GENERATE_ARTIFACTS_METADATA: "true"

The metadata renders in a plain text .json file stored with the artifact. The filename is {ARTIFACT_NAME}-metadata.json. ARTIFACT_NAME is the name for the artifact defined in the .gitlab-ci.yml file. If the name is not defined, the default filename is artifacts-metadata.json.

Provenance metadata format

The provenance metadata is generated in the in-toto attestation format for spec version 1.0.

To use an SLSA v1.0 statement, set the SLSA_PROVENANCE_SCHEMA_VERSION=v1 variable in the .gitlab-ci.yml file.

The following fields are populated by default:

Field Value
_type https://in-toto.io/Statement/v0.1
subject.name The filename of the artifact.
subject.digest.sha256 The artifact’s sha256 checksum.
predicateType https://slsa.dev/provenance/v0.2
predicate.buildType https://gitlab.com/gitlab-org/gitlab-runner/-/blob/{GITLAB_RUNNER_VERSION}/PROVENANCE.md. For example v15.0.0
predicate.builder.id A URI pointing to the runner details page, for example https://gitlab.com/gitlab-com/www-gitlab-com/-/runners/3785264.
predicate.invocation.configSource.uri https://gitlab.example.com/.../{PROJECT_NAME}
predicate.invocation.configSource.digest.sha256 The repository’s sha256 checksum.
predicate.invocation.configSource.entryPoint The name of the CI job that triggered the build.
predicate.invocation.environment.name The name of the runner.
predicate.invocation.environment.executor The runner executor.
predicate.invocation.environment.architecture The architecture on which the CI job is run.
predicate.invocation.parameters The names of any CI/CD or environment variables that were present when the build command was run. The value is always represented as an empty string to avoid leaking any secrets.
metadata.buildStartedOn The time when the build was started. RFC3339 formatted.
metadata.buildEndedOn The time when the build ended. Since metadata generation happens during the build this moment in time is slightly earlier than the one reported in GitLab. RFC3339 formatted.
metadata.reproducible Whether the build is reproducible by gathering all the generated metadata. Always false.
metadata.completeness.parameters Whether the parameters are supplied. Always true.
metadata.completeness.environment Whether the builder’s environment is reported. Always true.
metadata.completeness.materials Whether the build materials are reported. Always false.

An example of provenance metadata that the GitLab Runner might generate is as follows: 

{
 "_type": "https://in-toto.io/Statement/v0.1",
 "predicateType": "https://slsa.dev/provenance/v1",
 "subject": [
  {
   "name": "build/pico_w/wifi/blink/picow_blink.uf2",
   "digest": {
    "sha256": "f5a381a3fdf095a88fb928094f0e38cf269d226b07414369e8906d749634c090"
   }
  },
  {
   "name": "build/pico_w/wifi/blink/picow_blink.0.1.148-2-new-feature49.cosign.bundle",
   "digest": {
    "sha256": "f8762bf0b3ea1b88550b755323bf04417c2bbe9e50010cfcefc1fa877e2b52a6"
   }
  },
  {
   "name": "build/pico_w/wifi/blink/pico-examples-3a.0.1.148-2-new-feature49.tar.gz",
   "digest": {
    "sha256": "104674887da894443ab55918d81b0151dc7abb2472e5dafcdd78e7be71098af1"
   }
  },
  {
   "name": "build/pico_w/wifi/blink/pico-examples-3a.0.1.148-2-new-feature49.tar.gz.cosign.bundle",
   "digest": {
    "sha256": "33f3f7a19779a2d189dc03b420eb0be199a38404e8c1a24b2c8731bdfa3a30fb"
   }
  }
 ],
 "predicate": {
  "buildDefinition": {
   "buildType": "https://gitlab.com/gitlab-org/gitlab-runner/-/blob/761ae5dd/PROVENANCE.md",
   // All other CI variable names are listed here. Values are always represented as empty strings to avoid leaking secrets and to comply with SLSA.
   "externalParameters": {
    "CI": "",
    "CI_API_GRAPHQL_URL": "",
    "CI_API_V4_URL": "",
    "CI_COMMIT_AUTHOR": "",
    "CI_COMMIT_BEFORE_SHA": "",
    "CI_COMMIT_BRANCH": "",
    "CI_COMMIT_DESCRIPTION": "",
    "CI_COMMIT_MESSAGE": "",
    "CI_COMMIT_REF_NAME": "",
    "CI_COMMIT_REF_PROTECTED": "",
    "CI_COMMIT_REF_SLUG": "",
    "CI_COMMIT_SHA": "",
    "CI_COMMIT_SHORT_SHA": "",
    "CI_COMMIT_TIMESTAMP": "",
    "CI_COMMIT_TITLE": "",
    "CI_CONFIG_PATH": "",
    "CI_DEFAULT_BRANCH": "",
    "CI_DEPENDENCY_PROXY_DIRECT_GROUP_IMAGE_PREFIX": "",
    "CI_DEPENDENCY_PROXY_GROUP_IMAGE_PREFIX": "",
    "CI_DEPENDENCY_PROXY_PASSWORD": "",
    "CI_DEPENDENCY_PROXY_SERVER": "",
    "CI_DEPENDENCY_PROXY_USER": "",
    "CI_JOB_ID": "",
    "CI_JOB_NAME": "",
    "CI_JOB_NAME_SLUG": "",
    "CI_JOB_STAGE": "",
    "CI_JOB_STARTED_AT": "",
    "CI_JOB_TOKEN": "",
    "CI_JOB_URL": "",
    "CI_NODE_TOTAL": "",
    "CI_OPEN_MERGE_REQUESTS": "",
    "CI_PAGES_DOMAIN": "",
    "CI_PAGES_URL": "",
    "CI_PIPELINE_CREATED_AT": "",
    "CI_PIPELINE_ID": "",
    "CI_PIPELINE_IID": "",
    "CI_PIPELINE_NAME": "",
    "CI_PIPELINE_SOURCE": "",
    "CI_PIPELINE_URL": "",
    "CI_PROJECT_CLASSIFICATION_LABEL": "",
    "CI_PROJECT_DESCRIPTION": "",
    "CI_PROJECT_ID": "",
    "CI_PROJECT_NAME": "",
    "CI_PROJECT_NAMESPACE": "",
    "CI_PROJECT_NAMESPACE_ID": "",
    "CI_PROJECT_PATH": "",
    "CI_PROJECT_PATH_SLUG": "",
    "CI_PROJECT_REPOSITORY_LANGUAGES": "",
    "CI_PROJECT_ROOT_NAMESPACE": "",
    "CI_PROJECT_TITLE": "",
    "CI_PROJECT_URL": "",
    "CI_PROJECT_VISIBILITY": "",
    "CI_REGISTRY": "",
    "CI_REGISTRY_IMAGE": "",
    "CI_REGISTRY_PASSWORD": "",
    "CI_REGISTRY_USER": "",
    "CI_REPOSITORY_URL": "",
    "CI_RUNNER_DESCRIPTION": "",
    "CI_RUNNER_ID": "",
    "CI_RUNNER_TAGS": "",
    "CI_SERVER_FQDN": "",
    "CI_SERVER_HOST": "",
    "CI_SERVER_NAME": "",
    "CI_SERVER_PORT": "",
    "CI_SERVER_PROTOCOL": "",
    "CI_SERVER_REVISION": "",
    "CI_SERVER_SHELL_SSH_HOST": "",
    "CI_SERVER_SHELL_SSH_PORT": "",
    "CI_SERVER_URL": "",
    "CI_SERVER_VERSION": "",
    "CI_SERVER_VERSION_MAJOR": "",
    "CI_SERVER_VERSION_MINOR": "",
    "CI_SERVER_VERSION_PATCH": "",
    "CI_TEMPLATE_REGISTRY_HOST": "",
    "COSIGN_YES": "",
    "DS_EXCLUDED_ANALYZERS": "",
    "DS_EXCLUDED_PATHS": "",
    "DS_MAJOR_VERSION": "",
    "DS_SCHEMA_MODEL": "",
    "GITLAB_CI": "",
    "GITLAB_FEATURES": "",
    "GITLAB_USER_EMAIL": "",
    "GITLAB_USER_ID": "",
    "GITLAB_USER_LOGIN": "",
    "GITLAB_USER_NAME": "",
    "GitVersion_FullSemVer": "",
    "GitVersion_LegacySemVer": "",
    "GitVersion_Major": "",
    "GitVersion_MajorMinorPatch": "",
    "GitVersion_Minor": "",
    "GitVersion_Patch": "",
    "GitVersion_SemVer": "",
    "RUNNER_GENERATE_ARTIFACTS_METADATA": "",
    "SAST_EXCLUDED_ANALYZERS": "",
    "SAST_EXCLUDED_PATHS": "",
    "SAST_IMAGE_SUFFIX": "",
    "SCAN_KUBERNETES_MANIFESTS": "",
    "SECRETS_ANALYZER_VERSION": "",
    "SECRET_DETECTION_EXCLUDED_PATHS": "",
    "SECRET_DETECTION_IMAGE_SUFFIX": "",
    "SECURE_ANALYZERS_PREFIX": "",
    "SIGSTORE_ID_TOKEN": "",
    "entryPoint": "create_generic_package",
    "source": "https://gitlab.com/dsanoy-demo/experiments/pico-examples-3a"
   },
   "internalParameters": {
    "architecture": "amd64",
    "executor": "docker+machine",
    "job": "7211908025",
    "name": "green-6.saas-linux-small-amd64.runners-manager.gitlab.com/default"
   },
   "resolvedDependencies": [
    {
     "uri": "https://gitlab.com/dsanoy-demo/experiments/pico-examples-3a",
     "digest": {
      "sha256": "7e1aeac4e6c07138769b638d4926f429692d0124"
     }
    }
   ]
  },
  "runDetails": {
   "builder": {
    "id": "https://gitlab.com/dsanoy-demo/experiments/pico-examples-3a/-/runners/32976645",
    "version": {
     "gitlab-runner": "761ae5dd"
    }
   },
   "metadata": {
    "invocationID": "7211908025",
    "startedOn": "2024-06-28T09:56:44Z",
    "finishedOn": "2024-06-28T09:56:58Z"
   }
  }
 }
}

To verify compliance with the in-toto specification, see the in-toto statement.

Staging directory

History

If you do not want to archive cache and artifacts in the system’s default temporary directory, you can specify a different directory.

You might need to change the directory if your system’s default temporary path has constraints. If you use a fast disk for the directory location, it can also improve performance.

To change the directory, set ARCHIVER_STAGING_DIR as a variable in your CI job, or use a runner variable when you register the runner (gitlab register --env ARCHIVER_STAGING_DIR=<dir>).

The directory you specify is used as the location for downloading artifacts prior to extraction. If the fastzip archiver is used, this location is also used as scratch space when archiving.

Configure fastzip to improve performance

History

To tune fastzip, ensure the FF_USE_FASTZIP flag is enabled. Then use any of the following environment variables.

Variable Description
FASTZIP_ARCHIVER_CONCURRENCY The number of files to be concurrently compressed. Default is the number of CPUs available.
FASTZIP_ARCHIVER_BUFFER_SIZE The buffer size allocated per concurrency for each file. Data exceeding this number moves to scratch space. Default is 2 MiB.
FASTZIP_EXTRACTOR_CONCURRENCY The number of files to be concurrency decompressed. Default is the number of CPUs available.

Files in a zip archive are appended sequentially. This makes concurrent compression challenging. fastzip works around this limitation by compressing files concurrently to disk first, and then copying the result back to zip archive sequentially.

To avoid writing to disk and reading the contents back for smaller files, a small buffer per concurrency is used. This setting can be controlled with FASTZIP_ARCHIVER_BUFFER_SIZE. The default size for this buffer is 2 MiB, therefore, a concurrency of 16 allocates 32 MiB. Data that exceeds the buffer size is written to and read back from disk. Therefore, using no buffer, FASTZIP_ARCHIVER_BUFFER_SIZE: 0, and only scratch space is a valid option.

FASTZIP_ARCHIVER_CONCURRENCY controls how many files are compressed concurrency. As mentioned above, this setting therefore can increase how much memory is being used, but also how much temporary data is written to the scratch space. The default is the number of CPUs available, but given the memory ramifications, this may not always be the best setting.

FASTZIP_EXTRACTOR_CONCURRENCY controls how many files are decompressed at once. Files from a zip archive can natively be read from concurrency, so no additional memory is allocated in addition to what the decompressor requires. This defaults to the number of CPUs available.