GC (Virtually Zero-Overhead Object Management)

[Sean Kelly]

Craig Black wrote:
> "Sean Kelly" <sean at f4.ca> wrote in message 
> news:ekiu16$1ndk$1 at digitaldaemon.com...
>> zz wrote:
>>> While having a discussion about GC's with a friend, he brought up this 
>>> link which I found quite interesting (at the first reading) and I thought 
>>> others would also find it interesting.
>>>
>>> I'm still very skeptical of the claims.
>> Don't be.  Chris Thomasson may talk a bit big at times, but he has a solid 
>> grasp of the problems involved and VZOOM has gotten a lot of attention 
>> lately from some pretty respectable sources (I think it just won some kind 
>> of award in a contest sponsored by Sun or some such).  I haven't given 
>> VZOOM a very close look myself, but what I've heard Chris say about it 
>> makes me believe that it probably lives up to his claims. What makes VZOOM 
>> so fast, from what I've heard, is that it almost completely avoids the use 
>> of memory synchronization instructions through the use of some clever 
>> tricks, along the lines of RCU + SMR.  Last I heard Chris was working on a 
>> lock-free GC which sounded fairly promising, though it was smart-pointer 
>> based and therefore not really suitable for D.
> 
> Why not?  If someone has discovered a good GC solution via smart pointers 
> and reference counting, why couldn't D leverage this new technology somehow? 

I suppose it depends how the smart pointers are implemented.  As D 
doesn't support copy semantics for objects, there is really no way to 
implement traditional smart pointers.  Rather, the reference counting 
has to be done somewhat manually.


Sean