|
|
@@ -210,10 +210,9 @@ drivers: `aufs`, `devicemapper`, `btrfs`, `zfs`, `overlay` and `overlay2`.
|
|
|
|
|
|
The `aufs` driver is the oldest, but is based on a Linux kernel patch-set that
|
|
|
is unlikely to be merged into the main kernel. These are also known to cause
|
|
|
-some serious kernel crashes. However, `aufs` is also the only storage driver
|
|
|
-that allows containers to share executable and shared library memory, so is a
|
|
|
-useful choice when running thousands of containers with the same program or
|
|
|
-libraries.
|
|
|
+some serious kernel crashes. However, `aufs` allows containers to share
|
|
|
+executable and shared library memory, so is a useful choice when running
|
|
|
+thousands of containers with the same program or libraries.
|
|
|
|
|
|
The `devicemapper` driver uses thin provisioning and Copy on Write (CoW)
|
|
|
snapshots. For each devicemapper graph location – typically
|
|
|
@@ -235,7 +234,10 @@ cached only once. Use `dockerd -s zfs`. To select a different zfs filesystem
|
|
|
set `zfs.fsname` option as described in [Storage driver options](#storage-driver-options).
|
|
|
|
|
|
The `overlay` is a very fast union filesystem. It is now merged in the main
|
|
|
-Linux kernel as of [3.18.0](https://lkml.org/lkml/2014/10/26/137). Call
|
|
|
+Linux kernel as of [3.18.0](https://lkml.org/lkml/2014/10/26/137). `overlay`
|
|
|
+also supports page cache sharing, this means multiple containers accessing
|
|
|
+the same file can share a single page cache entry (or entries), it makes
|
|
|
+`overlay` as efficient with memory as `aufs` driver. Call
|
|
|
`dockerd -s overlay` to use it.
|
|
|
|
|
|
> **Note:**
|
Sebastiaan van Stijn