The absolute minimum that average users of the C++ memory ordering system in std atomic loads, etc. [1] should know is that the default memory access scheme is 'sequentially consistent ordering', whereas to get the ultimate performance, one should use the 'relaxed' scheme, or alternatively use 'release/acquire' as described both in the article and in [1].<p>[1] <a href="http://en.cppreference.com/w/cpp/atomic/memory_order" rel="nofollow">http://en.cppreference.com/w/cpp/atomic/memory_order</a>