Strange ZFS problem, filesystem claims to be full when clearly not full

[Jeremy Chadwick]

On Thu, Sep 30, 2010 at 04:38:46PM +0200, Oliver Fromme wrote:
> Danny Carroll <fbsd at dannysplace.net> wrote:
>  > [...]
>  > It certainly smells like a process still writing to a file that is unlinked.
>  > I wonder if it would show up with lsof.
> 
> If it's a file that was unlinked that is still held open by
> a process, then lsof will definitely list it.  The command
> 
> # lsof +L1
> 
> lists all open files with a link count of zero.  You can
> restrict it to a certain file system like this:
> 
> # lsof +aL1 /var
> 
> Of course, lsof won't list the file name because the file
> doesn't have a name anymore.  But it lists the process by
> name, PID and user, the file system and the file size.

Can someone explain how use of lsof in this regard is different than use
of fstat(1) like I originally mentioned?  Does lsof do something more
thorough or differently that what fstat does?

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |