> (linux tmpfs also uses virtually no extra ram due to using
   > other kernel cache objects (ie, vnode/inode/directory) rather
   > than keeping track of them with private structure.  i wonder
   > if those ideas could be adapted for our tmpfs?)
   
   i guess it just means linux have to use extra ram for
   mandated namecache (dcache) otherwise.


do we currently duplicate his data?  it seems no matter where
it goes, not duplicating data should save memory as well as
potentially avoid stale-data use (though this really would
indicate a bug somewhere i think?)