[boost] [sync] [thread] Faster mutex

Hi, One of the Mesa developers implemented a faster mutex: http://lists.freedesktop.org/archives/mesa-dev/2015-January/075260.html According to the sources of glibc, Mesa's mutex has a much smaller size (only 1 uint32_t vs 6 ints + 2 pointers), performs less actions before and after the actual syscall (no getting and setting of the mutex->__data.__owner, no type field checks) This gives an ~10% speedup. Just curious, maybe ideas from Mesa's mutex could be useful for some of the Boost libraries. -- Best regards, Antony Polukhin