Re: panic: mb_dtor_pack: ref_cnt != 1

Thierry Herbelot wrote:
> Le Friday 4 November 2005 17:35, Giorgos Keramidas a écrit :
> 
>>On 2005-11-04 17:12, Andre Oppermann <andre_at_freebsd.org> wrote:
>>
>>>Ok, thanks to Danny Braniss and Peter Holm the KASSERT is working now.
>>
>>Very fast fix.  Thanks.  I barely had the time to build a kernel and
>>read Peter's warning about a broken build, before the fix was ready :)
>>
> 
> Hello,
> 
> I have applied your second patch, to solve an mbuf exhaustion which I see with 
> NFS traffic.
> I still have the same symptoms : 
> after launching over an ssh session a recusrive 'ls' over an NFS disk, the 
> -current NFS client is blocked (and complains with 'nfs server truc:/files: 
> not responding') - I first saw this when cvs-ing the sources from the same 
> shared disk.
> 
> I have enclosed the trace showing the mbuf stats :
> 
> multi-cur% while (1)
> while? sleep 10
> while? netstat -m | head -2
> while? end
> 65/460/525 mbufs in use (current/cache/total)
> 64/210/274/3776 mbuf clusters in use (current/cache/total/max)
> 66/2124/2190 mbufs in use (current/cache/total)
> 64/2016/2080/3776 mbuf clusters in use (current/cache/total/max)
> 68/3652/3720 mbufs in use (current/cache/total)
> 65/3439/3504/3776 mbuf clusters in use (current/cache/total/max)
> 67/3908/3975 mbufs in use (current/cache/total)
> 64/3712/3776/3776 mbuf clusters in use (current/cache/total/max)
> 67/3908/3975 mbufs in use (current/cache/total)
> 64/3712/3776/3776 mbuf clusters in use (current/cache/total/max)
> 
> This isssue is seen on 3 different PCs running recent -current, clients for a 
> FreeBSD-6 NFS server (same problem when the NFS server is NetBSD). All 3 
> clients have a small RAM, which may be a cause for faster apparition of the 
> issue.

Hmmm...  There are way too many in the packet cache (zone). Normally they
should get free'd back into the mbuf and cluster zones if there are too many.
I have to track down why UMA isn't doing that.

-- 
Andre