Re: basic questions on MPS

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

Thanks for the explanation?

  > This can be implemented with hardware or software (or a combination).
  > Hardware barriers use the MMU via syscalls.

Do the CPUs we use nowadays have hardware features for that?
What aout the CPUs in the newest non=backdoored machines, such
as the Thinkpad t800 and x200s?

                                                 Software barriers are a
  > data structure that must be updated on every read (or write) operation.
  > This requires compiler assistance or disciplined programmers.

That sounds rather slow.  But maybe you have practical experience to
measure it.  Can GCC insert this cod eautomatically?  Or does Emacs do
it manually?  Either way, how much slowdown does it actually cause?

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)