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stage | group | info | type |
---|---|---|---|
Enablement | Distribution | To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments | reference |
Object storage (FREE SELF)
GitLab supports using an object storage service for holding numerous types of data. It's recommended over NFS and in general it's better in larger setups as object storage is typically much more performant, reliable, and scalable.
Options
GitLab has been tested on a number of object storage providers:
- Amazon S3
- Google Cloud Storage
- Digital Ocean Spaces
- Oracle Cloud Infrastructure
- OpenStack Swift
- Azure Blob storage
- On-premises hardware and appliances from various storage vendors.
- MinIO. We have a guide to deploying this within our Helm Chart documentation.
Known compatibility issues
-
Dell EMC ECS: Prior to GitLab 13.3, there is a known bug in GitLab Workhorse that prevents HTTP Range Requests from working with CI job artifacts. Be sure to upgrade to GitLab 13.3.0 or above if you use S3 storage with this hardware.
-
Ceph S3 prior to Kraken 11.0.2 does not support the Upload Copy Part API. You may need to disable multi-threaded copying.
Configuration guides
There are two ways of specifying object storage configuration in GitLab:
- Consolidated form: A single credential is shared by all supported object types.
- Storage-specific form: Every object defines its own object storage connection and configuration.
For more information on the differences and to transition from one form to another, see Transition to consolidated form.
Consolidated object storage configuration
Introduced in GitLab 13.2.
Using the consolidated object storage configuration has a number of advantages:
- It can simplify your GitLab configuration since the connection details are shared across object types.
- It enables the use of encrypted S3 buckets.
- It uploads files to S3 with proper
Content-MD5
headers.
Because direct upload mode must be enabled, only the following providers can be used:
When consolidated object storage is used, direct upload is enabled automatically. Background upload is not supported. For storage-specific configuration, direct upload may become the default because it does not require a shared folder.
Consolidated object storage configuration can't be used for backups or Mattermost. See the full table for a complete list.
Enabling consolidated object storage enables object storage for all object types. If you want to use local storage for specific object types, you can selectively disable object storages.
Most types of objects, such as CI artifacts, LFS files, upload attachments, and so on can be saved in object storage by specifying a single credential for object storage with multiple buckets.
When the consolidated form is:
- Used with an S3-compatible object storage, Workhorse uses its internal S3 client to upload files.
- Not used with an S3-compatible object storage, Workhorse falls back to using pre-signed URLs.
See the section on ETag mismatch errors for more details.
In Omnibus installations:
-
Edit
/etc/gitlab/gitlab.rb
and add the following lines, substituting the values you want:# Consolidated object storage configuration gitlab_rails['object_store']['enabled'] = true gitlab_rails['object_store']['proxy_download'] = true gitlab_rails['object_store']['connection'] = { 'provider' => 'AWS', 'region' => '<eu-central-1>', 'aws_access_key_id' => '<AWS_ACCESS_KEY_ID>', 'aws_secret_access_key' => '<AWS_SECRET_ACCESS_KEY>' } # OPTIONAL: The following lines are only needed if server side encryption is required gitlab_rails['object_store']['storage_options'] = { 'server_side_encryption' => '<AES256 or aws:kms>', 'server_side_encryption_kms_key_id' => '<arn:aws:kms:xxx>' } gitlab_rails['object_store']['objects']['artifacts']['bucket'] = '<artifacts>' gitlab_rails['object_store']['objects']['external_diffs']['bucket'] = '<external-diffs>' gitlab_rails['object_store']['objects']['lfs']['bucket'] = '<lfs-objects>' gitlab_rails['object_store']['objects']['uploads']['bucket'] = '<uploads>' gitlab_rails['object_store']['objects']['packages']['bucket'] = '<packages>' gitlab_rails['object_store']['objects']['dependency_proxy']['bucket'] = '<dependency-proxy>' gitlab_rails['object_store']['objects']['terraform_state']['bucket'] = '<terraform-state>' gitlab_rails['object_store']['objects']['pages']['bucket'] = '<pages>'
For GitLab 9.4 or later, if you're using AWS IAM profiles, be sure to omit the AWS access key and secret access key/value pairs. For example:
gitlab_rails['object_store']['connection'] = { 'provider' => 'AWS', 'region' => '<eu-central-1>', 'use_iam_profile' => true }
-
Save the file and reconfigure GitLab for the changes to take effect.
In installations from source:
-
Edit
/home/git/gitlab/config/gitlab.yml
and add or amend the following lines:object_store: enabled: true proxy_download: true connection: provider: AWS aws_access_key_id: <AWS_ACCESS_KEY_ID> aws_secret_access_key: <AWS_SECRET_ACCESS_KEY> region: <eu-central-1> storage_options: server_side_encryption: <AES256 or aws:kms> server_side_encryption_key_kms_id: <arn:aws:kms:xxx> objects: artifacts: bucket: <artifacts> external_diffs: bucket: <external-diffs> lfs: bucket: <lfs-objects> uploads: bucket: <uploads> packages: bucket: <packages> dependency_proxy: bucket: <dependency_proxy> terraform_state: bucket: <terraform> pages: bucket: <pages>
-
Edit
/home/git/gitlab-workhorse/config.toml
and add or amend the following lines:[object_storage] provider = "AWS" [object_storage.s3] aws_access_key_id = "<AWS_ACCESS_KEY_ID>" aws_secret_access_key = "<AWS_SECRET_ACCESS_KEY>"
-
Save the file and restart GitLab for the changes to take effect.
Common parameters
In the consolidated configuration, the object_store
section defines a
common set of parameters. Here we use the YAML from the source
installation because it's easier to see the inheritance:
object_store:
enabled: true
proxy_download: true
connection:
provider: AWS
aws_access_key_id: <AWS_ACCESS_KEY_ID>
aws_secret_access_key: <AWS_SECRET_ACCESS_KEY>
objects:
...
The Omnibus configuration maps directly to this:
gitlab_rails['object_store']['enabled'] = true
gitlab_rails['object_store']['proxy_download'] = true
gitlab_rails['object_store']['connection'] = {
'provider' => 'AWS',
'aws_access_key_id' => '<AWS_ACCESS_KEY_ID',
'aws_secret_access_key' => '<AWS_SECRET_ACCESS_KEY>'
}
Setting | Description |
---|---|
enabled |
Enable or disable object storage. |
proxy_download |
Set to true to enable proxying all files served. Option allows to reduce egress traffic as this allows clients to download directly from remote storage instead of proxying all data. |
connection |
Various connection options described below. |
storage_options |
Options to use when saving new objects, such as server side encryption. Introduced in GitLab 13.3. |
objects |
Object-specific configuration. |
Connection settings
Both consolidated configuration form and storage-specific configuration form must configure a connection. The following sections describe parameters that can be used
in the connection
setting.
S3-compatible connection settings
The connection settings match those provided by fog-aws:
Setting | Description | Default |
---|---|---|
provider |
Always AWS for compatible hosts. |
AWS |
aws_access_key_id |
AWS credentials, or compatible. | |
aws_secret_access_key |
AWS credentials, or compatible. | |
aws_signature_version |
AWS signature version to use. 2 or 4 are valid options. Digital Ocean Spaces and other providers may need 2 . |
4 |
enable_signature_v4_streaming |
Set to true to enable HTTP chunked transfers with AWS v4 signatures. Oracle Cloud S3 needs this to be false . |
true |
region |
AWS region. | |
host |
S3 compatible host for when not using AWS. For example, localhost or storage.example.com . HTTPS and port 443 is assumed. |
s3.amazonaws.com |
endpoint |
Can be used when configuring an S3 compatible service such as MinIO, by entering a URL such as http://127.0.0.1:9000 . This takes precedence over host . |
(optional) |
path_style |
Set to true to use host/bucket_name/object style paths instead of bucket_name.host/object . Leave as false for AWS S3. |
false . |
use_iam_profile |
Set to true to use IAM profile instead of access keys. |
false |
Oracle Cloud S3 connection settings
Note that Oracle Cloud S3 must be sure to use the following settings:
Setting | Value |
---|---|
enable_signature_v4_streaming |
false |
path_style |
true |
If enable_signature_v4_streaming
is set to true
, you may see the
following error in production.log
:
STREAMING-AWS4-HMAC-SHA256-PAYLOAD is not supported
Google Cloud Storage (GCS)
Here are the valid connection parameters for GCS:
Setting | Description | Example |
---|---|---|
provider |
Provider name. | Google |
google_project |
GCP project name. | gcp-project-12345 |
google_client_email |
Email address of the service account. | foo@gcp-project-12345.iam.gserviceaccount.com |
google_json_key_location |
JSON key path. | /path/to/gcp-project-12345-abcde.json |
google_application_default |
Set to true to use Google Cloud Application Default Credentials to locate service account credentials. |
The service account must have permission to access the bucket. Learn more in Google's Cloud Storage authentication documentation.
Google example (consolidated form)
For Omnibus installations, this is an example of the connection
setting:
gitlab_rails['object_store']['connection'] = {
'provider' => 'Google',
'google_project' => '<GOOGLE PROJECT>',
'google_client_email' => '<GOOGLE CLIENT EMAIL>',
'google_json_key_location' => '<FILENAME>'
}
Google example with ADC (consolidated form)
Introduced in GitLab 13.6.
Google Cloud Application Default Credentials (ADC) are typically used with GitLab to use the default service account. This eliminates the need to supply credentials for the instance. For example:
gitlab_rails['object_store']['connection'] = {
'provider' => 'Google',
'google_project' => '<GOOGLE PROJECT>',
'google_application_default' => true
}
If you use ADC, be sure that:
-
The service account that you use has the
iam.serviceAccounts.signBlob
permission. Typically this is done by granting theService Account Token Creator
role to the service account. -
Your virtual machines have the correct access scopes to access Google Cloud APIs. If the machines do not have the right scope, the error logs may show:
Google::Apis::ClientError (insufficientPermissions: Request had insufficient authentication scopes.)
Azure Blob storage
Introduced in GitLab 13.4.
Although Azure uses the word container
to denote a collection of
blobs, GitLab standardizes on the term bucket
. Be sure to configure
Azure container names in the bucket
settings.
Azure Blob storage can only be used with the consolidated form because a single set of credentials are used to access multiple containers. The storage-specific form is not supported. For more details, see how to transition to consolidated form.
The following are the valid connection parameters for Azure. Read the Azure Blob storage documentation to learn more.
Setting | Description | Example |
---|---|---|
provider |
Provider name. | AzureRM |
azure_storage_account_name |
Name of the Azure Blob Storage account used to access the storage. | azuretest |
azure_storage_access_key |
Storage account access key used to access the container. This is typically a secret, 512-bit encryption key encoded in base64. | czV2OHkvQj9FKEgrTWJRZVRoV21ZcTN0Nnc5eiRDJkYpSkBOY1JmVWpYbjJy\nNHU3eCFBJUQqRy1LYVBkU2dWaw==\n |
azure_storage_domain |
Domain name used to contact the Azure Blob Storage API (optional). Defaults to blob.core.windows.net . Set this if you are using Azure China, Azure Germany, Azure US Government, or some other custom Azure domain. |
blob.core.windows.net |
Azure example (consolidated form)
For Omnibus installations, this is an example of the connection
setting:
gitlab_rails['object_store']['connection'] = {
'provider' => 'AzureRM',
'azure_storage_account_name' => '<AZURE STORAGE ACCOUNT NAME>',
'azure_storage_access_key' => '<AZURE STORAGE ACCESS KEY>',
'azure_storage_domain' => '<AZURE STORAGE DOMAIN>',
}
Azure Workhorse settings (source installs only)
For source installations, Workhorse also needs to be configured with Azure credentials. This isn't needed in Omnibus installs, because the Workhorse settings are populated from the previous settings.
-
Edit
/home/git/gitlab-workhorse/config.toml
and add or amend the following lines:[object_storage] provider = "AzureRM" [object_storage.azurerm] azure_storage_account_name = "<AZURE STORAGE ACCOUNT NAME>" azure_storage_access_key = "<AZURE STORAGE ACCESS KEY>"
If you are using a custom Azure storage domain, note that
azure_storage_domain
does not have to be set in the Workhorse
configuration. This information is exchanged in an API call between
GitLab Rails and Workhorse.
OpenStack-compatible connection settings
Although OpenStack Swift provides S3 compatibility, some users may want to use the Swift API.
This isn't compatible with the consolidated object storage form. OpenStack Swift is supported only with the storage-specific form. If you want to use the consolidated form, see the S3 settings.
Here are the valid connection settings for the Swift API, provided by fog-openstack:
Setting | Description | Default |
---|---|---|
provider |
Always OpenStack for compatible hosts. |
OpenStack |
openstack_username |
OpenStack username. | |
openstack_api_key |
OpenStack API key. | |
openstack_temp_url_key |
OpenStack key for generating temporary URLs | |
openstack_auth_url |
OpenStack authentication endpoint | |
openstack_region |
OpenStack region. | |
openstack_tenant |
OpenStack tenant ID. |
Rackspace Cloud Files
The following table describes the valid connection parameters for Rackspace Cloud, provided by fog-rackspace.
This isn't compatible with the consolidated object storage form. Rackspace Cloud is supported only with the storage-specific form.
Setting | Description | Example |
---|---|---|
provider |
Provider name. | Rackspace |
rackspace_username |
Username of the Rackspace account with access to the container. | joe.smith |
rackspace_api_key |
API key of the Rackspace account with access to the container. | ABC123DEF456ABC123DEF456ABC123DE |
rackspace_region |
Rackspace storage region to use, a three letter code from the list of service access endpoints. | iad |
rackspace_temp_url_key |
Private key you set in the Rackspace API for temporary URLs. | ABC123DEF456ABC123DEF456ABC123DE |
Regardless of whether the container has public access enabled or disabled, Fog
uses the TempURL method to grant access to LFS objects. If you see error
messages in logs that refer to instantiating storage with a temp-url-key
,
be sure you have set the key properly both in the Rackspace API and in
gitlab.rb
. You can verify the value of the key Rackspace has set by sending a
GET request with token header to the service access endpoint URL and comparing
the output of the returned headers.
Object-specific configuration
The following YAML shows how the object_store
section defines
object-specific configuration block and how the enabled
and
proxy_download
flags can be overridden. The bucket
is the only
required parameter within each type:
object_store:
connection:
...
objects:
artifacts:
bucket: artifacts
proxy_download: false
external_diffs:
bucket: external-diffs
lfs:
bucket: lfs-objects
uploads:
bucket: uploads
packages:
bucket: packages
dependency_proxy:
enabled: false
bucket: dependency_proxy
terraform_state:
bucket: terraform
pages:
bucket: pages
This maps to this Omnibus GitLab configuration:
gitlab_rails['object_store']['objects']['artifacts']['bucket'] = 'artifacts'
gitlab_rails['object_store']['objects']['artifacts']['proxy_download'] = false
gitlab_rails['object_store']['objects']['external_diffs']['bucket'] = 'external-diffs'
gitlab_rails['object_store']['objects']['lfs']['bucket'] = 'lfs-objects'
gitlab_rails['object_store']['objects']['uploads']['bucket'] = 'uploads'
gitlab_rails['object_store']['objects']['packages']['bucket'] = 'packages'
gitlab_rails['object_store']['objects']['dependency_proxy']['enabled'] = false
gitlab_rails['object_store']['objects']['dependency_proxy']['bucket'] = 'dependency-proxy'
gitlab_rails['object_store']['objects']['terraform_state']['bucket'] = 'terraform-state'
gitlab_rails['object_store']['objects']['pages']['bucket'] = 'pages'
This is the list of valid objects
that can be used:
Type | Description |
---|---|
artifacts |
CI artifacts |
external_diffs |
Merge request diffs |
uploads |
User uploads |
lfs |
Git Large File Storage objects |
packages |
Project packages (for example, PyPI, Maven, or NuGet) |
dependency_proxy |
GitLab Dependency Proxy |
terraform_state |
Terraform state files |
pages |
GitLab Pages |
Within each object type, three parameters can be defined:
Setting | Required? | Description |
---|---|---|
bucket |
{check-circle} Yes | Bucket name for the object storage. |
enabled |
{dotted-circle} No | Overrides the common parameter. |
proxy_download |
{dotted-circle} No | Overrides the common parameter. |
Selectively disabling object storage
As seen above, object storage can be disabled for specific types by
setting the enabled
flag to false
. For example, to disable object
storage for CI artifacts:
gitlab_rails['object_store']['objects']['artifacts']['enabled'] = false
A bucket is not needed if the feature is disabled entirely. For example, no bucket is needed if CI artifacts are disabled with this setting:
gitlab_rails['artifacts_enabled'] = false
Transition to consolidated form
Prior to GitLab 13.2:
- Object storage configuration for all types of objects such as CI/CD artifacts, LFS files, upload attachments, and so on had to be configured independently.
- Object store connection parameters such as passwords and endpoint URLs had to be duplicated for each type.
For example, an Omnibus GitLab install might have the following configuration:
# Original object storage configuration
gitlab_rails['artifacts_object_store_enabled'] = true
gitlab_rails['artifacts_object_store_direct_upload'] = true
gitlab_rails['artifacts_object_store_proxy_download'] = true
gitlab_rails['artifacts_object_store_remote_directory'] = 'artifacts'
gitlab_rails['artifacts_object_store_connection'] = { 'provider' => 'AWS', 'aws_access_key_id' => 'access_key', 'aws_secret_access_key' => 'secret' }
gitlab_rails['uploads_object_store_enabled'] = true
gitlab_rails['uploads_object_store_direct_upload'] = true
gitlab_rails['uploads_object_store_proxy_download'] = true
gitlab_rails['uploads_object_store_remote_directory'] = 'uploads'
gitlab_rails['uploads_object_store_connection'] = { 'provider' => 'AWS', 'aws_access_key_id' => 'access_key', 'aws_secret_access_key' => 'secret' }
Although this provides flexibility in that it makes it possible for GitLab to store objects across different cloud providers, it also creates additional complexity and unnecessary redundancy. Since both GitLab Rails and Workhorse components need access to object storage, the consolidated form avoids excessive duplication of credentials.
The consolidated object storage configuration is used only if all lines from
the original form is omitted. To move to the consolidated form, remove the
original configuration (for example, artifacts_object_store_enabled
, or
uploads_object_store_connection
)
Storage-specific configuration
For configuring object storage in GitLab 13.1 and earlier, or for storage types not supported by consolidated configuration form, refer to the following guides:
Object storage type | Supported by consolidated configuration? |
---|---|
Backups | {dotted-circle} No |
Job artifacts including archived job logs | {check-circle} Yes |
LFS objects | {check-circle} Yes |
Uploads | {check-circle} Yes |
Container Registry (optional feature) | {dotted-circle} No |
Merge request diffs | {check-circle} Yes |
Mattermost | {dotted-circle} No |
Packages (optional feature) | {check-circle} Yes |
Dependency Proxy (optional feature) (PREMIUM SELF) | {check-circle} Yes |
Pseudonymizer (optional feature) (ULTIMATE SELF) | {dotted-circle} No |
Autoscale runner caching (optional for improved performance) | {dotted-circle} No |
Terraform state files | {check-circle} Yes |
GitLab Pages content | {check-circle} Yes |
Other alternatives to file system storage
If you're working to scale out your GitLab implementation, or add fault tolerance and redundancy, you may be looking at removing dependencies on block or network file systems. See the following additional guides:
- Make sure the
git
user home directory is on local disk. - Configure database lookup of SSH keys
to eliminate the need for a shared
authorized_keys
file. - Prevent local disk usage for job logs.
Warnings, limitations, and known issues
Use separate buckets
Using separate buckets for each data type is the recommended approach for GitLab. This ensures there are no collisions across the various types of data GitLab stores. There are plans to enable the use of a single bucket in the future.
Helm-based installs require separate buckets to handle backup restorations.
S3 API compatibility issues
Not all S3 providers are fully compatible
with the Fog library that GitLab uses. Symptoms include an error in production.log
:
411 Length Required
Proxy Download
Clients can download files in object storage by receiving a pre-signed, time-limited URL, or by GitLab proxying the data from object storage to the client. Downloading files from object storage directly helps reduce the amount of egress traffic GitLab needs to process.
When the files are stored on local block storage or NFS, GitLab has to act as a proxy. This is not the default behavior with object storage.
The proxy_download
setting controls this behavior: the default is generally false
.
Verify this in the documentation for each use case. Set it to true
if you want
GitLab to proxy the files.
When not proxying files, GitLab returns an HTTP 302 redirect with a pre-signed, time-limited object storage URL. This can result in some of the following problems:
-
If GitLab is using non-secure HTTP to access the object storage, clients may generate
https->http
downgrade errors and refuse to process the redirect. The solution to this is for GitLab to use HTTPS. LFS, for example, generates this error:LFS: lfsapi/client: refusing insecure redirect, https->http
-
Clients need to trust the certificate authority that issued the object storage certificate, or may return common TLS errors such as:
x509: certificate signed by unknown authority
-
Clients need network access to the object storage. Network firewalls could block access. Errors that might result if this access is not in place include:
Received status code 403 from server: Forbidden
Getting a 403 Forbidden
response is specifically called out on the
package repository documentation
as a side effect of how some build tools work.
Additionally for a short time period users could share pre-signed, time-limited object storage URLs with others without authentication. Also bandwidth charges may be incurred between the object storage provider and the client.
ETag mismatch
Using the default GitLab settings, some object storage back-ends such as
MinIO
and Alibaba
might generate ETag mismatch
errors.
If you are seeing this ETag mismatch error with Amazon Web Services S3, it's likely this is due to encryption settings on your bucket. To fix this issue, you have two options:
The first option is recommended for MinIO. Otherwise, the
workaround for MinIO
is to use the --compat
parameter on the server.
Without consolidated object store configuration or instance profiles enabled,
GitLab Workhorse uploads files to S3 using pre-signed URLs that do
not have a Content-MD5
HTTP header computed for them. To ensure data
is not corrupted, Workhorse checks that the MD5 hash of the data sent
equals the ETag header returned from the S3 server. When encryption is
enabled, this is not the case, which causes Workhorse to report an ETag mismatch
error during an upload.
With the consolidated object configuration and instance profile, Workhorse has
S3 credentials so that it can compute the Content-MD5
header. This
eliminates the need to compare ETag headers returned from the S3 server.
Using Amazon instance profiles
Instead of supplying AWS access and secret keys in object storage configuration, GitLab can be configured to use IAM roles to set up an Amazon instance profile. When this is used, GitLab fetches temporary credentials each time an S3 bucket is accessed, so no hard-coded values are needed in the configuration.
Encrypted S3 buckets
- Introduced in GitLab 13.1 for instance profiles only and S3 default encryption.
- Introduced in GitLab 13.2 for static credentials when consolidated object storage configuration and S3 default encryption are used.
When configured either with an instance profile or with the consolidated object configuration, GitLab Workhorse properly uploads files to S3 buckets that have SSE-S3 or SSE-KMS encryption enabled by default. Note that customer master keys (CMKs) and SSE-C encryption are not supported since this requires sending the encryption keys in every request.
Server-side encryption headers
Introduced in GitLab 13.3.
Setting a default encryption on an S3 bucket is the easiest way to
enable encryption, but you may want to set a bucket policy to ensure
only encrypted objects are uploaded.
To do this, you must configure GitLab to send the proper encryption headers
in the storage_options
configuration section:
Setting | Description |
---|---|
server_side_encryption |
Encryption mode (AES256 or aws:kms ). |
server_side_encryption_kms_key_id |
Amazon Resource Name. Only needed when aws:kms is used in server_side_encryption . See the Amazon documentation on using KMS encryption. |
As with the case for default encryption, these options only work when the Workhorse S3 client is enabled. One of the following two conditions must be fulfilled:
use_iam_profile
istrue
in the connection settings.- Consolidated object storage settings are in use.
ETag mismatch errors occur if server side encryption headers are used without enabling the Workhorse S3 client.
IAM Permissions
To set up an instance profile:
-
Create an Amazon Identity Access and Management (IAM) role with the necessary permissions. The following example is a role for an S3 bucket named
test-bucket
:{ "Version": "2012-10-17", "Statement": [ { "Sid": "VisualEditor0", "Effect": "Allow", "Action": [ "s3:PutObject", "s3:GetObject", "s3:DeleteObject" ], "Resource": "arn:aws:s3:::test-bucket/*" } ] }
-
Attach this role to the EC2 instance hosting your GitLab instance.
-
Configure GitLab to use it via the
use_iam_profile
configuration option.
Multi-threaded copying
GitLab uses the S3 Upload Part Copy API to accelerate the copying of files within a bucket. Ceph S3 prior to Kraken 11.0.2 does not support this and returns a 404 error when files are copied during the upload process.
The feature can be disabled using the :s3_multithreaded_uploads
feature flag. To disable the feature, ask a GitLab administrator with
Rails console access
to run the following command:
Feature.disable(:s3_multithreaded_uploads)