Subj : Re: [.NET] Volatile Fields
To   : comp.programming.threads
From : Cool Guy
Date : Sun Sep 18 2005 04:43 pm

David Schwartz <davids@webmaster.com> wrote:

>     There are three things that cause problems for multi-threaded programs 
> on typical modern SMP machines:
> 
>     1) Instruction re-ordering. This is where the compiler or the processor 
> internally performs instructions in a different order from that in the 
> high-level code.

So, with this issue, the reads/writes - when they're made - *will* be made
in a way that other threads can see them -- but the only problem is that
they might happen too late or too early, right?

>     2) Posted writes. This is where the CPU does not output a write to its 
> cache immediately but instead puts it in a temporary holding place. (Not the 
> L2 cache, but a posted write buffer.)
> 
>     3) Speculative fetches. This is where the CPU reads data before it needs 
> it and keeps the data for a later instruction.

So I assume memory barriers solve all three problems?

.