vlruwk deadlock (was: NFS troubles on recent -current.)

[Robert Watson]

On Fri, 16 May 2003, Bernd Walter wrote:

> I had an io deadlook on the same server today while doing a make release
> on an alpha nfs client.  I don't know if it is related to the given
> patch or not.  It happened shortly after the client checked out the
> ports.  Sorry - I forgot to take a dump. 

I've been running into similar sorts of deadlocks on my diskless crash
boxes, and have dropped some information to Don on them.  Try the
following also from ddb: 

print numvnodes
print desiredvnodes
print vnlruproc_sig
print vnlru_nowhere

This will print some information on the number of active vnodes; one of
the characteristics of my nfs client/server box in its deadlocked state is
that it has exceeded the maximum number of vnodes, presumably by
necessity.

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Network Associates Laboratories