[no subject]

>>  9275 ?        D      2:02 du -k
>> 10103 ?        D      2:26 /usr/bin/find / ( -fstype NFS -o -fstype nfs -o
>> 21671 ?        D      1:28 /usr/bin/rsync -a --delete -H -x .  >> /mounts/local0.yesterday/
>> 13976 ?        D      1:16 du -k
>> 14776 ?        D      1:59 /usr/bin/find / ( -fstype NFS -o -fstype nfs -o

All operations that require filesystem locks.  They are queued up
behind some task that has grabbed a filesystem lock and is hung, IOW
these tasks are innocent victims of the real problem.  99.9%
probability that the real problem is a hung NFS event.

If you have kdb installed and active, drop into kdb and
  set LOGGING 1
  bta RD
  go
The trace will show what the hung tasks are waiting on.