From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: [RFC] Subvolume Quota on-disk structures and configuration Date: Mon, 21 Nov 2011 13:29:38 -0500 Message-ID: <4ECA9892.9070801@cfl.rr.com> References: <4E19611D.2090007@gmx.net> <4ECA7721.3040607@cfl.rr.com> <4ECA8847.2080905@gmx.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linux-btrfs To: Arne Jansen Return-path: In-Reply-To: <4ECA8847.2080905@gmx.net> List-ID: On 11/21/2011 12:20 PM, Arne Jansen wrote: > On 11/21/2011 05:06 PM, Phillip Susi wrote: >> On 7/10/2011 4:21 AM, Arne Jansen wrote: >>> btrfs qgroup limit [--exclusive]|none >>> >>> >>> btrfs qgroup limit 10g /usr >>> >>> That should be simple enough for the common use case. >> >> Wouldn't that make the syntax above actually be: >> >> btrfs qgroup limit [--exclusive] [qgroupid] > > You don't mean to actually changing the syntax, but adding a better > explanation or a more precise usage? What I mean is that your syntax listed in angle brackets, indicating that it is a required argument, but your description seems to indicate that it is optional, so it should be in square brackets. Also the size bit I assume was meant to be a required parameter that should be either a number or the word none, so the angle brackets should enclose the |none part too. >> I also have a question about the interactions with groups of groups. Say >> I have 4 subvolumes: 1, 2, 3, and Z. I group the first 3 volumes and >> set a limit on them. Now if all 3 volumes share a chunk of space, that >> space should only count towards the group once, rather than 3 times. > > It's just what groups are made for. In your scenario the chunk of space > would count only once. Some hopefully better explanation can be found at Ohh, so the group is a union of the chunks in the members, not a sum? So if you set an exclusive limit on the group, that would count everything shared between 1, 2, 3 once, and not count any shared with Z? In other words, --exclusive excludes space shared with things outside the group, not within it? > http://sensille.com/qgroups.pdf > > Have you already played with the patchset? Not yet; I just found it today from the new thread on the subject, and look forward to playing with it tonight. I was wondering what revision the patches are based on, and are they in a public git repo?