quota

func NewControl ¶

func NewControl(basePath string) (*Control, error)

NewControl - initialize project quota support. Test to make sure that quota can be set on a test dir and find the first project id to be used for the next container create.

Returns nil (and error) if project quota is not supported.

First get the project id of the home directory. This test will fail if the backing fs is not xfs.

xfs_quota tool can be used to assign a project id to the driver home directory, e.g.:

echo 999:/var/lib/docker/overlay2 >> /etc/projects
echo docker:999 >> /etc/projid
xfs_quota -x -c 'project -s docker' /<xfs mount point>

In that case, the home directory project id will be used as a "start offset" and all containers will be assigned larger project ids (e.g. >= 1000). This is a way to prevent xfs_quota management from conflicting with docker.

Then try to create a test directory with the next project id and set a quota on it. If that works, continue to scan existing containers to map allocated project ids.