On Friday, 18 April 2014 at 14:15:00 UTC, Steven Schveighoffer
wrote:
And an inc/dec may not necessarily need a lock if the array
element is not shared, even if you inc/dec the ref count.
D offers opportunities to go beyond traditional ref count
eliding.
In most situations where you need speed you do need to share data
so that you can keep 8 threads busy without trashing the caches
and getting the memory bus as a bottle neck.
Then you somehow have to tell the compiler what the mutex covers
if ARC is going to be transparent… E.g. "this mutex covers all
strings reachable from pointer P". So you need a meta level
language…
But even still, 150-200 extra cycles here and there is not as
bad as a 300ms pause to collect garbage for some apps.
I don't know. I think one unified management strategy will not
work in most real time apps. I think C++ got that right.
I also think you need both meta level reasoning (program
verification constructs) and whole program analysis to get a
performant solution with automatic management.
I think nobody is arguing that Ref counting is a magic bullet
to memory management. It fits some applications better than GC,
that's all.
As an addition to other management techniques, yes.
