As we have just seen, there are two basic ways of scheduling threads: process

local scheduling (known as Process Contention Scope, or Unbound Threads—the

Many-to-Many model) and system global scheduling (known as System Contention

Scope, or Bound Threads—the One-to-One model). These scheduling classes are

known as the scheduling contention scope, and are defined only in POSIX. Process

contention scope scheduling means that all of the scheduling mechanism for the

thread is local to the process—the threads library has full control over which

thread will be scheduled on an LWP. This also implies the use of either the Many-

to-One or Many-to-Many model.