debugging mbuf allocation/dealocation

[Nikola Knežević]

Hi,

I'm trying to make some code which uses a lot of mbufs (Click modular  
router) running under FreeBSD 7.1. The problem is that it is leaking  
mbufs, and I can't find where...

After running the Click in a configuration which generates 150k  
packets (using m_dup) and discards them (m_freem), I get this in  
netstat -m output:
150258/1302/151560 mbufs in use (current/cache/total)
256/828/1084/4672 mbuf clusters in use (current/cache/total/max)
256/768 mbuf+clusters out of packet secondary zone in use (current/ 
cache)
0/135/135/2336 4k (page size) jumbo clusters in use (current/cache/ 
total/max)
0/0/0/1168 9k jumbo clusters in use (current/cache/total/max)
0/0/0/584 16k jumbo clusters in use (current/cache/total/max)
38076K/2521K/40598K bytes allocated to network (current/cache/total)
0/0/0 requests for mbufs denied (mbufs/clusters/mbuf+clusters)
0/0/0 requests for jumbo clusters denied (4k/9k/16k)
0/0/0 sfbufs in use (current/peak/max)
0 requests for sfbufs denied
0 requests for sfbufs delayed
0 requests for I/O initiated by sendfile
0 calls to protocol drain routines


So, my question is: how to debug this? How can I track the usage of  
mbufs, profile it, and such? I'm running Click as a kernel module.

Thanks,
Nikola