Re: [RFC PATCH] tmpfs: support user quotas

Lennart Poettering
2011-11-08T00:25:22Z

On Mon, 07.11.11 23:43, Alan Cox (alan@lxorguk.ukuu.org.uk) wrote:

>
> On Tue, 8 Nov 2011 00:07:12 +0100
> Lennart Poettering <mzxreary@0pointer.de> wrote:
>
> > On Mon, 07.11.11 22:53, Alan Cox (alan@lxorguk.ukuu.org.uk) wrote:
> >
> > > Per user would be quota, per process would be rlimit. Quite simple
> > > really, nice standard interfaces we've had for years. Various systems
> >
> > Uh, have you ever really looked at resource limits? Some of them are
> > per-user, not per-process, i.e. RLIMIT_NPROC. And this would just be
> > another one.
>
> NPROC is a bit of an oddity.

And half of the other resource limits are "oddities" too?
For example RLIMIT_SIGPENDING is per-user and so is RLIMIT_MSGQUEUE,
and others too.

> And the standards have no idea how a resource limit hit for an fs would
> be reported, nor how an app installer would check for it. Quota on the
> other hand is defined behaviour.

EDQUOT is POSIX, but afaik there is no POSIX standardized API for quota,
is there? i.e. the reporting of the user hitting quota is defined, but
how to set the quota is left open. Which is nice, since it gives us the
flexibility to use resource limits here, since they so nicely apply to
the problem.

Lennart

--
Lennart Poettering - Red Hat, Inc.