If someone has a more elegant solution, feel free to share it
spin_thread = 0
spin_thread = 1 // the faster but GS thread will never stop, very bad for laptop
It is faster on linux, it requires less code, and it is "portable"
It requires boost (only hpp files) + MSVC 2013 (for atomic) (seem doable by 2012 too)
Actually there are several queues that either use spinlock or full sleep