77:  Why does Emacs take 20 seconds to visit a file?

  The usual cause is that the master lock file, "!!!SuperLock!!!" has been
  left in the lock directory somehow.  Delete it.

  Mark Meuer <meuer@geom.umn.edu> says that NeXT NFS has a bug where an
  exclusive create succeeds but returns an error status.  This can cause
  the same problem.  Since Emacs's file locking doesn't work over NFS
  anyway, the best solution is to recompile Emacs with CLASH_DETECTION
  undefined.