Persistent list

[Dicebot via Digitalmars-d]

On Friday, 13 November 2015 at 23:10:04 UTC, Andrei Alexandrescu 
wrote:
> I created a simple persistent list with reference counting and 
> custom allocation at http://dpaste.dzfl.pl/0981640c2835.


There is also another thing I wanted to mention on topic of 
persistent containers. Right now for me the most intriguing topic 
is trying to define immutable (and actually thread shared) cache 
data structure than can be efficiently and safely used without 
GC. There is whole class of tasks where you can get best 
performance by building new copy of cache in memory instead of 
modifying separate elements, trading increased memory 
concsumption for fast no lock parallel access. However in absence 
of GC task of deleting memory for older generations of cache 
becomes rather challenging. I have been thinking about approach 
with external two-level reference counting + dedicated allocator 
- quick thread-local RC comes first and once it goes to 0, shared 
RC in allocator gets decremented (being effetively user thread 
counter). Do you think it can work?