unionfs

README

Fuse based Union FS Graph Driver

EXPERIMENTAL!

Note that this is still in development and experimental. Currently the following are known issues

1. Data modified on shared layers are not snap'd and therefore visible in other containers.
2. There are two heavy weight locks around accessing the UFS data structures which can be avoided.

About

The unionfs graph driver leverages the kernel-userspace communication protocol fuse to implement the storage of graph layers.

It also uses an optimized way of computing the layer diffs and avoids using the NaiveDiff implementation.

To use this as the graphdriver in Docker with btrfs as the backend volume provider:

DOCKER_STORAGE_OPTIONS= -s unionfs --storage-opt unionfs.volume_driver=btrfs

or

docker daemon --storage-driver=unionfs --storage-opt unionfs.volume_driver=btrfs

Building

Make sure you have fuse installed.

When building OSD, run:

HAVE_UNIONFS=1 EXPERIMENTAL_=1 make

Documentation

Index

• Constants
• func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error)

Constants

const (
	Name = "unionfs"
	Type = api.Graph
)

Functions

func Init

func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error)