Message passing

[Jonathan Shapiro]

   A similar application to application protocol (namely, passing the
   application data in more than one kernel message) could also be used to
   advantage in lieu of scatter/gather, if you really want to avoid an
   extra copy of the data. KeyKOS message passing is fast.

Fast is relative.  I know the KeyKOS context switch path is very fast,
but on most processors, a KeyKOS context switch implies a TLB flush,
which slows things down.  If transferring a large block of network
data requires several context switches, the transfer will suffer.

On the other hand, this is probably a case for shared segments.


Jonathan