Nullfs leaks i-nodes

[Mikolaj Golub]

On Tue, May 07, 2013 at 08:30:06AM +0200, Göran Löwkrantz wrote:
> I created a PR, kern/178238, on this but would like to know if anyone has 
> any ideas or patches?
> 
> Have updated the system where I see this to FreeBSD 9.1-STABLE #0 r250229 
> and still have the problem.

I am observing an effect that might look like inode leak, which I
think is due free nullfs vnodes caching, recently added by kib
(r240285): free inode number does not increase after unlink; but if I
purge the free vnodes cache (temporary setting vfs.wantfreevnodes to 0
and observing vfs.freevnodes decreasing to 0) the inode number grows
back.

You have only about 1000 inodes available on your underlying fs, while
vfs.wantfreevnodes I think is much higher, resulting in running out of
i-nodes.

If it is really your case you can disable caching, mounting nullfs
with nocache (it looks like caching is not important in your case).

-- 
Mikolaj Golub