- My multibranch pipeline clones the entire repository on the master to obtain the Jenkinsfile
- My multibranch pipeline shows a timeout error when cloning the repository to obtain the Jenkinsfile:
Branch indexing 23:43:32 Connecting to https://api.github.com using my-credentials/****** (my-credentials GitHub personal access token) Checking out git https://github.com/org/repo.git into /var/jenkins_home/workspace/_repo_PR-123-P7DALB4WUZUT3GSAR3HPW2RCNJME43BF5FNLWOCKUK55BAHQV6SA@script to read Jenkinsfile Cloning the remote Git repository Cloning with configured refspecs honoured and without tags Cloning repository https://github.com/org/repo.git > git init /var/jenkins_home/workspace/_repo_PR-123-P7DALB4WUZUT3GSAR3HPW2RCNJME43BF5FNLWOCKUK55BAHQV6SA@script # timeout=10 Fetching upstream changes from https://github.com/org/repo.git > git --version # timeout=10 using GIT_ASKPASS to set credentials my-credentials GitHub personal access token > git fetch --no-tags --progress https://github.com/org/repo.git +refs/pull/123/head:refs/remotes/origin/PR-123 +refs/heads/master:refs/remotes/origin/master ERROR: Timeout after 10 minutes [...]
- CloudBees Jenkins Enterprise - Managed Master (CJEMM)
- CloudBees Jenkins Team (CJT)
- CloudBees Jenkins Platform - Client Master (CJPCM)
- Jenkins LTS
- Pipeline as Code
- Pipeline Multibranch Plugin
- JENKINS-33273: Optimize Jenkinsfile loading and branch detection
- JENKINS-43194: Lightweight checkout for PR merge jobs
- JENKINS-42518: Provide lightweight checkout capability for bitbucket to avoid repository clone for multi-branch pipeline jobs
Pipeline from SCM used to perform several checkout as explained in JENKINS-33273. Since version 2.13 of Pipeline Multibranch Plugin and the resolution of JENKINS-33273, Pipeline from SCM offers the ability to perform a lightweight checkout - if the SCM supports it - to retrieve the Jenkinsfile. With a lightweight checkout, no clone is needed to retrieve the Jenkinsfile anymore. The Jenkinsfile is instead retrieved using an API.
The following plugin provide support for lightweight checkout:
- Git Plugin since version 3.0.2
- Gitea Plugin
- GitHub Branch Source Plugin since version 2.0.0
- Bitbucket Branch Source Plugin since version 2.2.6
However in the case of merge Pull Requests only those versions of the plugins support a lightweight checkout:
In unsupported versions, plugin falls back to the previous behavior - a heavyweight checkout - which mean that a full clone is performed to retrieve the Jenkinsfile.
For such cases, there are workarounds that can be used until further support for a lightweight checkout is provided.
This workaround requires SCM API v2.2.0: Prior to that version, only the behavior of the
checkout step can be adjusted - see [How to Customize Checkout for Pipeline Multibranch? - but not the behavior of the checkout carried out to obtain the Jenkinsfile.
A reference repository is a general tip to speed up the checkout/cloning of large Git repository. You can set up a reference repository on the master that will serve as a cache for your repository. It also saves disk space and reduce the traffic between Jenkins and the Git server.
First, have a look at the article Using a Git reference repository to understand how to set up a reference repository.
Then, in the configuration of the organization / multibranch project, add an SCM Trait of type Advanced Clone Behaviors and specify the path to the reference repository:
If affected by the timeout error, it is possible to increase the Git timeout.
You can increase the timeout globally by setting the system property
-Dorg.jenkinsci.plugins.gitclient.Git.timeOut=<number of minutes> on startup. Upon restart, you can check that the timeout is properly set by running the groovy script
return org.jenkinsci.plugins.gitclient.CliGitAPIImpl.TIMEOUT under Manage Jenkins > Script Console.
SCM API v2.2.0 and later
You can set the timeout per organization / multibranch. In the configuration of organization / multibranch project, add the SCM Traits of type Advanced Clone Behaviors and Advanced Checkout Behaviors and set a suitable value for the timeout (in minutes):
Since version 2.2.0 of the SCM API Plugin, it is now possible to add SCM Traits - like the git additional behaviors - at the organization / multibranch level. These traits apply to:
- the checkout performed to retrieve the Jenkinsfile
SCM API v2.2+ along with GitHub Branch Source 2.2+ and Bitbucket Branch Source 2.2+ are available under the CloudBees Assurance Program since CJE 18.104.22.168.
Multibranch Pipelines support lightweight checkout since JENKINS-33273.
It is activated by default.
There is a kill switch to deactivate it.
org.jenkinsci.plugins.workflow.multibranch.USE_HEAVYWEIGHT_CHECKOUT=true to Jenkins arguments (please refer to How to add Java arguments to Jenkins?).
Why is my Pipeline job cloning the entire repository on the master even when I select a lightweight checkout?
In order to work the lightweight checkout needs a cache repository.
This cache repository is created the first time on the master.
Like for a standard Pipeline job, lightweight checkout needs a cache repository.
This is used for instance by the branch indexing feature.