Thoughts on Quotas

Justin C. Sherrill justin at
Sun Sep 26 08:01:58 PDT 2010

On Sun, September 26, 2010 8:32 am, Michael Neumann wrote:

> My usage scenario is a Fileserver with many users. One thing that comes
> to mind is to spend one PFS per user home directory. IIRC, HAMMER
> supports up to 2^16 PFS. In my case it is obvious that limiting the real
> diskspace used by each PFS would be a nice feature, not only in my case,
> but also imagine one PFS per vkernel or jail, which would give much
> stronger separation guaratees than what we have right now.

The one thing that comes immediately to mind is scale.  Usually, a
DragonFly system has less than 10 PFSs.  (What's the plural of PFS?) 
/home, /var, /usr, etc.  Having a per-user PFS setup seems appealing
because then you can set up snapshot and mirroring properties on a
per-user basis.

However, what happens where there's 200 users on a machine?  It would be
very frustrating to keep track of the settings of each user and to
implement changes on each, especially if some users get different settings
than others.  I think the user->PFS idea is good; it just may require a
different set of tools.

More information about the Kernel mailing list