[boost] Re: lightweight mutex

Just a note on the lightweight mutex for windows OS using Interlocked operations: I had one like this before (came with doug lee's allocator) and I ran some benchmarks and saw a ~10% improvement in performance in a non-contention situation. Now that benchmark may or may not have been valid, it's too long ago for me to say with certainty, but it raises the question, what are the numbers here? Also one does not need to use a spin lock on a ref counted implementation. A much faster (and safer) way to do that is just using InterlockedIncrement and InterlockedDecrement when changing the ref count. I beleive this is what most popular ref counting implementations use.