File system full

[Paul Khavkine]

I see.

Any way to find out what process is doing it ?

I doubt it's a local DoS since noone has shell access to the machine.


Thanx
Paul


Clifton Royston wrote:

> On Mon, Apr 05, 2004 at 12:00:53PM -0700, freebsd-hackers-request at freebsd.org wrote:
> > Date: Mon, 05 Apr 2004 14:49:42 -0400
> > From: Paul Khavkine <paul at colba.net>
> > Subject: File system full
> > To: freebsd-hackers at freebsd.org
> ...
> >
> > Today for i have noticed that the /tmp partition on one of our mail
> > servers was reported as
> > full. I have checked if there's any files in /tmp but found that it
> > wasn't true.
> >
> > du reports that /tmp is only using 50K.
> >
> > After a few minutes the size changed from 100% to 66%.
> >
> > Even that makes no sense:
> >
> > %df -h
> > ..
> > /dev/amrd0s1f                       492M   298M   155M    66%    /tmp
> >
> > %du -skh /tmp/
> >  16K    /tmp/
> >
> >
> > Any clues to why it behaves that way ?
>
>   Almost certainly a classic all-Un*x problem:
>
>   There are long-lived running processes holding already-deleted files
> open in /tmp.  Such files have already removed from the directories,
> and hence are not visible to ls or du, but can not be freed by the
> operating system until the process which opened them terminates, hence
> their space shows up in df and is not free for allocation.  This can be
> a form of local DOS, but it's more likely a coding/design error.
>
>   I've particularly run into this with Apache + mod_perl on a high-load
> website.  Apache keeps processes around for a relatively long time, and
> in the persistent perl environment, if files are not explicitly closed
> they remain open by the interpreter - so a Perl script which creates
> temp files and doesn't explicitly close them at the end of each
> execution pass can really rack up the disk space with "invisible"
> files.
>
>   -- Clifton
>
> --
>           Clifton Royston  --  cliftonr at tikitechnologies.com
>          Tiki Technologies Lead Programmer/Software Architect
> Did you ever fly a kite in bed?  Did you ever walk with ten cats on your head?
>   Did you ever milk this kind of cow?  Well we can do it.  We know how.
> If you never did, you should.  These things are fun, and fun is good.
>                                                                  -- Dr. Seuss