Re: 2.2.0 wishlist

Robert Glamm (glamm@mountains.ee.umn.edu)
Fri, 14 Jun 1996 10:11:33 -0500 (CDT)


> > Doh, someone tell me to RTFM... ;)
> >
> > I still don't think that it should ever be implemented. If you've got
> > home dirs on an almost-full disk (i.e., like 99%), you could conceivably
> > be ``wasting'' maybe 5, 10, even 20% on undeleted files, and the full disk
> > would become a needless annoyance (IMHO :). Does someone
> > have stats on how often & what size files are deleted/created/modeified
> > in a home directory structure? Almost sounds like a computer science
> > master's thesis topic to me.. ;)
>
> Well just to tell you to RTFM, it's in the file system, but it's not
> honored (hmm, I really don't like this spelling, but it's in my
> /usr/dict/words so ....) by the kernel (ie the kernel currently ignores
> these bits).
>
> Anyway, root still has 5% of the disk for cleaning up after the users
> (well assuming you didn't kill that off ;).

Oh, heh, that's one of the features I actually liked from Sun's filesystem
that was never implemented on the SGI systems I adminned. I've still got
that.

> If the undelete stuff was fixed, I'd want to have a cron job that scaned
> the undeleteable deleted files, and really got rid of them after a set
> time (depending on your avalable disk space anything from 1 hour to weeks).
>
> Also you'd have to make it a real pain for users to undelete stuff if the
> files arn't part of there quota (ie just keep the file's deletion date
> under 5 days, and it's never purged, instant free disk space).

Well, is it really necessary to set the timeout at longer than a day
on deleted files? From when I've wanted to recover files it's usually
''oh, crap, I just typed rm -rf on the wrong directory DOH!" and frantically
hit the break key to stop it before it purges everything; usually my recovery
time would be less than 15 minutes. I can see if you wrote a cron job that
ran at night you might want up to a day to undelete files, but I can't imagine
a case for a longer recovery period. Of course, I haven't thought about this
too hard either :)

> You could make sure it's part of there quota, and it's not a problem,
> except when you have users mailing that they can't save even though
> they've got no files in there home directory (though you could allow them
> access to the purge command in the same way is passwd works (ie 'passwd' is
> me, 'passwd user' is user, and only root can specify a user name).

Hmm... that's an interesting idea. A quota with soft, hard limits, along with
an 'undelete' space limit? That would make the undelete feature easier
to accept, I think. That way the people that didn't want that feature could
set the 'undelete' space limit to 0.

-- 
Bob Glamm                               | "You can't do a `goto' to a block
Email: glamm@mountains.ee.umn.edu       |  that has been optimized away.
URL:   http://www.cs.umn.edu/~glamm     |  Darn."
Home: (612)623-9437 Work: (612)625-7876 |    - from the perltrap(1) manpage