Update system df docs to call out performance implications

Signed-off-by: Wayne Song <wsong@docker.com>
Upstream-commit: d8a49c322ad08815c7321e411e036782db18d314
Component: engine
This commit is contained in:
Wayne Song
2017-03-22 09:49:03 +01:00
parent 57f09755b9
commit 10622096c6
@@ -77,6 +77,15 @@ my-named-vol 0
> **Note**: Network information is not shown because it doesn't consume the disk
> space.
## Performance
The `system df` command can be very resource-intensive. It traverses the
filesystem of every image, container, and volume in the system. You should be
careful running this command in systems with lots of images, containers, or
volumes or in systems where some images, containers, or volumes have very large
filesystems with many files. You should also be careful not to run this command
in systems where performance is critical.
## Related commands
* [system prune](system_prune.md)
* [container prune](container_prune.md)