|
|
@@ -7,7 +7,7 @@ module (dm-thinp) to implement CoW snapshots. For each devicemapper
|
|
|
graph location (typically `/var/lib/docker/devicemapper`, $graph below)
|
|
|
a thin pool is created based on two block devices, one for data and
|
|
|
one for metadata. By default these block devices are created
|
|
|
-automatically by using loopback mounts of automatically creates sparse
|
|
|
+automatically by using loopback mounts of automatically created sparse
|
|
|
files.
|
|
|
|
|
|
The default loopback files used are `$graph/devicemapper/data` and
|
|
|
@@ -15,15 +15,15 @@ The default loopback files used are `$graph/devicemapper/data` and
|
|
|
from docker entities to the corresponding devicemapper volumes is
|
|
|
stored in the `$graph/devicemapper/json` file (encoded as Json).
|
|
|
|
|
|
-In order to support multiple devicemapper graphs on a system the thin
|
|
|
+In order to support multiple devicemapper graphs on a system, the thin
|
|
|
pool will be named something like: `docker-0:33-19478248-pool`, where
|
|
|
the `0:33` part is the minor/major device nr and `19478248` is the
|
|
|
inode number of the $graph directory.
|
|
|
|
|
|
-On the thin pool docker automatically creates a base thin device,
|
|
|
+On the thin pool, docker automatically creates a base thin device,
|
|
|
called something like `docker-0:33-19478248-base` of a fixed
|
|
|
-size. This is automatically formatted on creation and contains just an
|
|
|
-empty filesystem. This device is the base of all docker images and
|
|
|
+size. This is automatically formatted with an empty filesystem on
|
|
|
+creation. This device is the base of all docker images and
|
|
|
containers. All base images are snapshots of this device and those
|
|
|
images are then in turn used as snapshots for other images and
|
|
|
eventually containers.
|
|
|
@@ -31,7 +31,7 @@ eventually containers.
|
|
|
### options
|
|
|
|
|
|
The devicemapper backend supports some options that you can specify
|
|
|
-when starting the docker daemon using the --storage-opt flags.
|
|
|
+when starting the docker daemon using the `--storage-opt` flags.
|
|
|
This uses the `dm` prefix and would be used something like `docker -d --storage-opt dm.foo=bar`.
|
|
|
|
|
|
Here is the list of supported options:
|
Michael Crosby