Message passing between threads: Java 4 times faster than D

[Sean Kelly]

On Feb 9, 2012, at 2:17 PM, Sean Kelly wrote:

> On Feb 9, 2012, at 11:57 AM, Martin Nowak wrote:
>> 
>> I didn't yet got around to polish my lock-free SList/DList implementations,
>> but mutexes should only become a problem with high contention when you need to block.
>> You'd also would need some kind of blocking for lock-free lists.
> 
> No blocking should be necessary for the lock-free list.  Just try to steal a node with a CAS.  If the result was null (i.e. if the list ended up being empty), allocate a node via malloc/GC.

I just realized that the free-list is actually a stack, so doing this lock-free runs into the ABA problem.  There goes the idea of this being an easy optimization.