John Dyson who wrote the FreeBSD VM system has recently analysed the situation and concluded that proper threads and SMP will never work on FreeBSD without a complete rewrite of the kernel. John Dyson said that in its current state, all attempts to implement proper threads and proper SMP on FreeBSD will only lead to an unmaintainable mess. John Dyson really knows the FreeBSD kernel. He further went on to say that such a rewrite would be impossible under the current politics which dominate the FreeBSD development process. According to John, it would take a major commitment on the whole FreeBSD developer community to scrap the current problematic base and rewrite it properly. Unlikely to happen in our lifetimes, but who really knows. [I believe he posted his analysis to the FBSD hackers list.]