The cost of write barriers

[deadalnix via Digitalmars-d]

On Sunday, 2 November 2014 at 08:48:46 UTC, Jonathan Barnard 
wrote:
> The upcoming version 1.4 of Go uses write barriers in 
> preparation for the future implementation of a concurrent and 
> generational GC. On the mailing list thread discussing the beta 
> (https://groups.google.com/forum/#!topic/golang-nuts/7VAcfULjiB8), 
> a few people note speed reductions of 30-50% in their 
> benchmarks. I think this vindicates to a degree D's decision to 
> avoid garbage collection strategies that require write barriers.

Write barrier are only required on objects that contain mutable 
pointer and are shared. in D, that is a subset of the shared 
heap. D's type system would allow to use such strategy while 
mitigating the cost quite a lot.