Re: You could do worse than Mach ports

[a <a@a>]

Terry Lambert wrote:
> Matthew Dillon wrote:
>
> >    Even something like cryptfs can conceivably, if a crypto chip is
> >    present, use DMA to directly access the data without it having to be
> >    mapped.  And if it isn't, so what?  You wind up mapping the data and
> >    take the performance hit.  Just because you might have to do it for
> >    some subsystems doesn't mean you should go and burden *ALL* the
> >    subsystems with that kind of overhead.
>
>
> Cache coherency.  It's a big problem.  Given the design information
> disclosed so far, the assumptions tend to make me believe that the
> coherency model would not work for NUMA, IA64 (more than 4 CPU),
> SPARC, PPC, and a number of other platforms.

Could someone address this issue?