Many of these implement semaphores to avoid race conditions.
Virtual machines may make use of a green variety of these constructs, while misordering of these can cause priority inversion. An Intel technology to implement these transparently in hardware was first introduced in the Xeon, and lC-slowing of these constructs can mimic "barrel" devices that use them. Instances of these that access I/O may be blocking, so that these are manipulated by a scheduler. These constructs are necessary to take advantage of (*) multi-core CPUs and to switch between them the OS must context switch. Many of these implement semaphores to avoid race conditions. For 10 points, name sub-processes created by a fork command that can run concurrently.
Virtual machines may make use of a green variety of these constructs, while misordering of these can cause priority inversion.
{Threads} [prompt on "{process}" until mentioned]