Update documentation to include a high-level description of ceph quotas. Signed-off-by: Luis Henriques <lhenriques@xxxxxxxx> --- Documentation/filesystems/ceph.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt index 0b302a11718a..094772481263 100644 --- a/Documentation/filesystems/ceph.txt +++ b/Documentation/filesystems/ceph.txt @@ -62,6 +62,18 @@ subdirectories, and a summation of all nested file sizes. This makes the identification of large disk space consumers relatively quick, as no 'du' or similar recursive scan of the file system is required. +Finally, Ceph also allows quotas to be set on any directory in the system. +The quota can restrict the number of bytes or the number of files stored +beneath that point in the directory hierarchy. Quotas can be set using +extended attributes 'ceph.quota.max_files' and 'ceph.quota.max_bytes', eg: + + setfattr -n ceph.quota.max_bytes -v 100000000 /some/dir + getfattr -n ceph.quota.max_bytes /some/dir + +A limitation of the current quotas implementation is that it relies on the +cooperation of the client mounting the file system to stop writers when a +limit is reached. A modified or adversarial client cannot be prevented +from writing as much data as it needs. Mount Syntax ============ -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
