On 06/27/2011 04:58 PM, Andrew Brunner wrote:
You're totally underestimating the need for a memory barrier :
While I do know that memory barriers are the way to go to avoid the
expensive use of Mutex and friends, I am positive that an MB is not
necessary if all accesses to something are protected by a Mutex, as same
is designed to block any thread independently from the CPU it is running
on. so no other thread can even try to access that memory location. (we
are not discussing how to construct a Mutex/FUTEX internally).
Focus on the "These primitives are usually implemented with the memory
barriers ...
Yep, "usually" as critical sections are much more expensive.
-Michael
--
_______________________________________________
Lazarus mailing list
[email protected]
http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
