Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 14 Mar 2005 19:25:42 +0000
From:      Chris Hodgins <chodgins@cis.strath.ac.uk>
To:        Anish Mistry <mistry.7@osu.edu>
Cc:        "Samuel J. Greear" <freebsd-hackers@evilcode.net>
Subject:   Re: Idea about 'skeleton jail
Message-ID:  <4235E536.6080601@cis.strath.ac.uk>
In-Reply-To: <200503141346.41722.mistry.7@osu.edu>
References:  <1107178792.613.22.camel@spirit> <200503131524.16075.mistry.7@osu.edu> <200503140915.53619.freebsd-hackers@evilcode.net> <200503141346.41722.mistry.7@osu.edu>

next in thread | previous in thread | raw e-mail | index | archive | help
Anish Mistry wrote:
> On Monday 14 March 2005 10:15 am, Samuel J. Greear wrote:
> 
>>On Sunday 13 March 2005 14:24, Anish Mistry wrote:
>>
>>>On Sunday 13 March 2005 01:23 pm, Chris Hodgins wrote:
>>>
>>>>Samuel J. Greear wrote:
>>>>
>>>>>Not a bad 'idea' at all, although I won't comment on
>>>>>semantics. I had something implemented using fs stacking (in
>>>>>a very hackish way, and I believe it's lost now, so don't ask
>>>>>to see it...) to implement per-jail quota's that seemed to
>>>>>work quite well.
>>>>>
>>>>>Sam
>>>>
>>>>Feel free to comment on the semantics.  As I said before, I am
>>>>not very knowledgable about filesystems and any insight or
>>>>alternative implementation you can provide would be interesting
>>>>I'm sure to everyone.
>>>
>>>Yeah, if there was jailfs that was setup automatically for the
>>>jails that supported quotas out of the box that would kill my
>>>major gripe about setting up jails.
>>
>>Chris, your concept looks reasonable to me. I think I would
>>probably do something along those lines but borrow some idea's from
>>my 'jail-build' script.  It has the concept of both includes and
>>excludes, but it also handles another directory for what I call
>>overrides.  My overrides directories are per-jail and typically
>>include nothing more than config. files, but it works pretty
>>handily.  The overrides may best be implemented in a seperate
>>layer...  and I don't even know that I would call something like
>>this a jailfs, more like a globfs or something...  I can see
>>potential uses beyond jails.
>>
>>The reasons that I never finished implementing my jailfs with quota
>>support were primarily, that stackable filesystems seem to be
>>somewhat of a black-art.  Secondarily, I concluded that the time
>>would be better spent implementing filesystem agnostic quota's in
>>the vfs layer.  A proper design should enable you to do a lot of
>>fun things, I was thinking something along the lines of just a
>>simple aggregator that a module could hand function pointers to and
>>register interest in events, with options like..  just-notify-me
>>and dont-continue-without-my-approval. Throw in some helpers for
>>synchronizing module state to disk. The kernel side of this
>>shouldn't really be very hard, but all of the userland quota
>>utilities would need to be rewritten as they are tied to UFS at the
>>block level.  This all from about 3 years ago, and I haven't
>>implemented any of it.  I rock!
>>
>>Sam
> 
> Would you be able to write up some design specs for getting all this 
> done?  This might be a prime example of something to try to get 
> funding for development.
> 

I seem to have stopped receiving mail from the mailing lists.  Would it 
be possible for someone to forward any replies on this thread for the 
last few hours to christopher.hodgins@gmail.com.  If it would be 
possible for any further emails to be cc'd there as well that would be 
brilliant. :)

Thanks
Chris



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4235E536.6080601>