- From: Julian Reschke <julian.reschke@gmx.de>
- Date: Wed, 08 Sep 2004 08:04:15 +0200
- To: Brian Korver <briank@xythos.com>
- CC: WebDAV <w3c-dist-auth@w3.org>
Brian Korver wrote:
> I was responding to an earlier suggestion that
> the model be scrapped in favor of one you proposed
> not doing. We agreed to the quota-by-resource model,
> no one has proposed doing any other, so the issue
> is resolved.
I can't remember that anybody agreed on that (pointer, please?). The
only p.o.v. that makes sense to me is that the Quota protocol only
discusses marshalling, but not the Quota system itself. Thus it should
work both with user/group-based and resource-based quota (and other
systems that may exist).
> But, to answer your questions: Yes, the NFS spec does
> seem to allow disk limits to me marshalled through
> the quota properties and certainly doesn't prohibit
> this ("the server is at liberty to choose"). NFS
> chooses to define these properties as read-only.
RFC3530, section 5.10:
Note that there may be a number of distinct but overlapping
sets of files or directories for which a quota_used value is
maintained (e.g., "all files with a given owner", "all files
with a given group owner", etc.).
The server is at liberty to choose any of those sets but should
do so in a repeatable way. The rule may be configured per-
filesystem or may be "choose the set with the smallest quota".
So no, this doesn't apply to disk limits - disk limits are *not* quotas.
RFC3530 discusses disk limits in section 5.6:
space_free 43 uint64 READ Free disk space in
bytes on the
filesystem
containing this
object - this should
be the smallest
relevant limit.
space_total 44 uint64 READ Total disk space in
bytes on the
filesystem
containing this
object.
space_used 45 uint64 READ Number of filesystem
bytes allocated to
this object.
Also note that RFC3530 distinguishes error conditions for both (section 12):
NFS4ERR_DQUOT Resource (quota) hard limit exceeded. The
user's resource limit on the server has been
exceeded.
and
NFS4ERR_NOSPC No space left on device. The operation would
have caused the server's filesystem to exceed
its limit.
So again, lett's just do what NFS does: define properties for quota and
disk limits, keep the quota definitions such as they are compatible with
existing quota systems, distinguish error conditions clearly and keep
things read-only.
Best regards, Julian
--
<green/>bytes GmbH -- http://www.greenbytes.de -- tel:+492512807760
Received on Wednesday, 8 September 2004 06:04:59 UTC