• Prerequisites
• Server configuration
  • Configure Azure Blob storage
  • Configure Google Cloud storage
  • Configure S3 storage
    • Configure S3-compatible servers
• Generating bundles
• Bundle URI example
• Securing bundles

Bundle URIs

Gitaly supports Git bundle URIs. Bundle URIs are locations where Git can download one or more bundles to bootstrap the object database before fetching the remaining objects from a remote. Bundle URIs are built in to the Git protocol.

Using Bundle URIs can:

• Speed up clones and fetches for users with a poor network connection to the GitLab server. The bundles can be stored on a CDN, making them available around the world.
• Reduce the load on servers that run CI/CD jobs. If CI/CD jobs can pre-load bundles from somewhere else, the remaining work to incrementally fetch missing objects and references creates a lot less load on the server.

Prerequisites

• The Git configuration transfer.bundleURI must be enabled on Git clients.
• GitLab Runner 16.6 or later.
• In CI/CD pipeline configuration, the default Git strategy set to git clone.

Server configuration

You must configure where the bundles are stored. Gitaly supports the following storage services:

• Google Cloud Storage
• AWS S3 (or compatible)
• Azure Blob Storage
• Local file storage (not recommended)

Configure Azure Blob storage

How you configure Azure Blob storage for Bundle URI depends on the type of installation you have. For self-compiled installations, you must set the AZURE_STORAGE_ACCOUNT and AZURE_STORAGE_KEY environment variables outside of GitLab.

gitaly['env'] = {
    'AZURE_STORAGE_ACCOUNT' => 'azure_storage_account',
    'AZURE_STORAGE_KEY' => 'azure_storage_key' # or 'AZURE_STORAGE_SAS_TOKEN'
}
gitaly['configuration'] = {
    bundle_uri: {
        go_cloud_url: 'azblob://<bucket>'
    }
}

[bundle_uri]
go_cloud_url = "azblob://<bucket>"

Configure Google Cloud storage

Google Cloud storage (GCP) authenticates using Application Default Credentials. Set up Application Default Credentials on each Gitaly server using either:

• The gcloud auth application-default login command.
• The GOOGLE_APPLICATION_CREDENTIALS environment variable. For self-compiled installations, set the environment variable outside of GitLab.

For more information, see Application Default Credentials.

The destination bucket is configured using the go_cloud_url option.

gitaly['env'] = {
    'GOOGLE_APPLICATION_CREDENTIALS' => '/path/to/service.json'
}
gitaly['configuration'] = {
    bundle_uri: {
        go_cloud_url: 'gs://<bucket>'
    }
}

[bundle_uri]
go_cloud_url = "gs://<bucket>"

Configure S3 storage

To configure S3 storage authentication:

• If you authenticate with the AWS CLI, you can use the default AWS session.
• Otherwise, you can use the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables. For self-compiled installations, set the environment variables outside of GitLab.

For more information, see AWS Session documentation.

The destination bucket and region are configured using the go_cloud_url option.

gitaly['env'] = {
    'AWS_ACCESS_KEY_ID' => 'aws_access_key_id',
    'AWS_SECRET_ACCESS_KEY' => 'aws_secret_access_key'
}
gitaly['configuration'] = {
    bundle_uri: {
        go_cloud_url: 's3://<bucket>?region=us-west-1'
    }
}

[bundle_uri]
go_cloud_url = "s3://<bucket>?region=us-west-1"

Configure S3-compatible servers

S3-compatible servers such as MinIO are configured similarly to S3 with the addition of the endpoint parameter.

The following parameters are supported:

• region: The AWS region.
• endpoint: The endpoint URL.
• disabledSSL: A value of true disables SSL.
• s3ForcePathStyle: A value of true forces path-style addressing.

gitaly['env'] = {
    'AWS_ACCESS_KEY_ID' => 'minio_access_key_id',
    'AWS_SECRET_ACCESS_KEY' => 'minio_secret_access_key'
}
gitaly['configuration'] = {
    bundle_uri: {
        go_cloud_url: 's3://<bucket>?region=minio&endpoint=my.minio.local:8080&disableSSL=true&s3ForcePathStyle=true'
    }
}

[bundle_uri]
go_cloud_url = "s3://<bucket>?region=minio&endpoint=my.minio.local:8080&disableSSL=true&s3ForcePathStyle=true"

Generating bundles

After Gitaly is properly configured, Gitaly can generate bundles, which is a manual process. To generate a bundle for Bundle URI, run:

sudo -u git -- /opt/gitlab/embedded/bin/gitaly bundle-uri \
                                               --config=<config-file> \
                                               --storage=<storage-name> \
                                               --repository=<relative-path>

This command generates the bundle and stores it on the configured storage service. Gitaly does not automatically refresh the generated bundle. When want to generate a more recent version of a bundle, you must the run command again.

You can schedule this command with a tool like cron(8).

Bundle URI example

In the following example, we demonstrate the difference between cloning gitlab.com/gitlab-org/gitlab.git with and without using bundle URI.

$ git -c transfer.bundleURI=false clone https://gitlab.com/gitlab-org/gitlab.git
Cloning into 'gitlab'...
remote: Enumerating objects: 5271177, done.
remote: Total 5271177 (delta 0), reused 0 (delta 0), pack-reused 5271177
Receiving objects: 100% (5271177/5271177), 1.93 GiB | 32.93 MiB/s, done.
Resolving deltas: 100% (4140349/4140349), done.
Updating files: 100% (71304/71304), done.

$ git -c transfer.bundleURI=true clone https://gitlab.com/gitlab-org/gitlab.git
Cloning into 'gitlab'...
remote: Enumerating objects: 1322255, done.
remote: Counting objects: 100% (611708/611708), done.
remote: Total 1322255 (delta 611708), reused 611708 (delta 611708), pack-reused 710547
Receiving objects: 100% (1322255/1322255), 539.66 MiB | 22.98 MiB/s, done.
Resolving deltas: 100% (1026890/1026890), completed with 223946 local objects.
Checking objects: 100% (8388608/8388608), done.
Checking connectivity: 1381139, done.
Updating files: 100% (71304/71304), done.

In the above example:

• When not using a Bundle URI, there were 5,271,177 objects received from the GitLab server.
• When using a Bundle URI, there were 1,322,255 objects received from the GitLab server.

This reduction means GitLab needs to pack together fewer objects (in the above example, roughly a quarter of the number of objects) because the client first downloaded the bundle from the storage server.

Securing bundles

The bundles are made accessible to the client using signed URLs. A signed URL is a URL that provides limited permissions and time to make a request. To see if your storage service supports sighed URLs, see the documentation of your storage service.