The issue

~# dmesg -T

    [Tue Jan 19 13:58:49 2016] statd: server rpc.statd not responding, timed out
    [Tue Jan 19 13:58:49 2016] lockd: cannot monitor koios

Possible solution

I found the answer to this on serverfault, in Debian/Ubuntu the commands would be:

~# service nfs-kernel-server stop
~# service rpcbind stop
~# service nfs-common stop
~# service rpcbind start
~# service nfs-common start
~# service nfs-kernel-server start

Debugging

I use rpcdebug to dedug rpc, i found a lot of information on archlinux wiki

~$ rpcdebug -vh

    usage: rpcdebug [-v] [-h] [-m module] [-s flags...|-c flags...]
           set or cancel debug flags.
    
    Module     Valid flags
    rpc        xprt call debug nfs auth bind sched trans svcsock svcdsp misc cache all
    nfs        vfs dircache lookupcache pagecache proc xdr file root callback client mount all
    nfsd       sock fh export svc proc fileop auth repcache xdr lockd all
    nlm        svc client clntlock svclock monitor clntsubs svcsubs hostcache xdr all

Examples:

    $ rpcdebug -m nfsd -s proc
    nfsd proc