OMP_PLACES and OMP_PROC_BIND

The OMP_PROC_BIND environment variable 
	sets the initial value of the bind-var ICV. 
The value of this environment variable is either 
	true, false,
	or a comma separated list of master, close, or spread. 
The values of the list set the thread affinity policy
	to be used for parallel regions at the corresponding nested level.

If the environment variable is set to false, 
	the execution environment may move OpenMP threads between OpenMP places, 
	thread affinity is disabled, 
	and proc_bind clauses on parallel constructs are ignored.

Otherwise, 
	the execution environment should not move OpenMP threads between OpenMP places, 
	thread affinity is enabled, 
	and the initial thread 
		is bound to the first place in the OpenMP place list 
		prior to the first active parallel region.