Calling pool_init() multiple times is bad. This happens when you kill nfsd on a machine.
Daniel does this fix your problem? ok? Index: nfs_syscalls.c =================================================================== RCS file: /cvs/src/sys/nfs/nfs_syscalls.c,v retrieving revision 1.91 diff -u -p -r1.91 nfs_syscalls.c --- nfs_syscalls.c 7 Aug 2010 03:50:02 -0000 1.91 +++ nfs_syscalls.c 3 Dec 2010 14:06:26 -0000 @@ -549,8 +549,9 @@ nfsrv_init(int terminating) M_WAITOK|M_ZERO); TAILQ_INSERT_HEAD(&nfssvc_sockhead, nfs_udpsock, ns_chain); - pool_init(&nfsrv_descript_pl, sizeof(struct nfsrv_descript), 0, 0, 0, - "ndscpl", &pool_allocator_nointr); + if (!terminating) + pool_init(&nfsrv_descript_pl, sizeof(struct nfsrv_descript), + 0, 0, 0, "ndscpl", &pool_allocator_nointr); } #endif /* NFSSERVER */