This function is not called during plugin initialization (#2140),
but should be useful for downstream projects that uses overlayfs
snapshotter as a Go library.
Benchmark result on Ubuntu 17.10, GCE n1-standard-4:
BenchmarkOverlaySupportedOnExt4-4 100 20490598 ns/op
BenchmarkOverlayUnsupportedOnFType0XFS-4 30000 39316 ns/op
BenchmarkOverlaySupportedOnFType1XFS-4 100 19287083 ns/op
BenchmarkOverlayUnsupportedOnFAT-4 100 14217772 ns/op
i.e. the overhead is typically about 20 msec on this machine.
Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
Use a smaller filesize on systems that have a default 4KB pagesize.
This is because mkfs.btrfs uses the default system pagesize as blocksize
when creating a device, so if the pagesize is larger, then the file needs
to be larger as well. This larger filesize is needed specifically for
systems where 64KB is default, such as ppc64le.
Signed-off-by: Christopher Jones <tophj@linux.vnet.ibm.com>
Allow configuring the overlay snapshotter to synchronously
or asynchronously do cleanup. When the driver is integrated
into a garbage collection system, the asynchronous cleanup
can reduce the time of removal and allow the longer disk
cleanup to be handled without locking the snapshotter.
Signed-off-by: Derek McGowan <derek@mcgstyle.net>
Updates overlay remove to simply remove the reference, adds
a cleanup method for discarding the directory.
Updates snapshot create to setup the directory structure while
in the transaction, to prevent cleanup from removing directories
which are part of a create.
Signed-off-by: Derek McGowan <derek@mcgstyle.net>
Cleans up loop devices if part of the test or mount process fails.
Also increases btrfs default file size to 650MB to accommodate
minimum btrfs size on ppc64le and s390x
Signed-off-by: Christopher Jones <tophj@linux.vnet.ibm.com>
This changes the Windows runtime to use the snapshotter and differ
created layers, and updates the ctr commands to use the snapshotter and differ.
Signed-off-by: Darren Stahl <darst@microsoft.com>
This implements the Windows snapshotter and diff Apply function.
This allows for Windows layers to be created, and layers to be pulled
from the hub.
Signed-off-by: Darren Stahl <darst@microsoft.com>
Implements btrfs usage using a double walking diff and
counting the result. Walking gives the most accurate
count and includes inode usage.
Signed-off-by: Derek McGowan <derek@mcgstyle.net>
