The cost of write barriers

[Jonathan Barnard via Digitalmars-d]

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.