On 3/16/22 12:19 AM, Luís Henriques wrote:
> Signed-off-by: Luís Henriques <[email protected]>
> ---
> Documentation/filesystems/ceph.rst | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/Documentation/filesystems/ceph.rst b/Documentation/filesystems/ceph.rst
> index 4942e018db85..d487cabe792d 100644
> --- a/Documentation/filesystems/ceph.rst
> +++ b/Documentation/filesystems/ceph.rst
> @@ -57,6 +57,16 @@ a snapshot on any subdirectory (and its nested contents) in the
> system. Snapshot creation and deletion are as simple as 'mkdir
> .snap/foo' and 'rmdir .snap/foo'.
>
> +Snapshot names have two limitations:
> +
> +* They can not start with an underscore ('_'), as these names are reserved
> + for internal usage by the MDS.
> +* They can not exceed 240 characters in size. This is because the MDS makes
> + use of long snapshot names internally, which follow the format:
> + `_<SNAPSHOT-NAME>_<INODE-NUMBER>`. Since filenames in general can't have
> + more than 255 characters, and `<node-id>` takes 13 characters, the long
> + snapshot names can take as much as 255 - 1 - 1 - 13 = 240.
> +
> Ceph also provides some recursive accounting on directories for nested
> files and bytes. That is, a 'getfattr -d foo' on any directory in the
> system will reveal the total number of nested regular files and
>
LGTM.
Reviewed-by: Xiubo Li <[email protected]>