Type Method


Sets the current thread’s priority.


+ (BOOL)setThreadPriority:(double)p;



The new priority, specified with a floating point number from 0.0 to 1.0, where 1.0 is highest priority.

Return Value

YES if the priority assignment succeeded, NO otherwise.


The priorities in this range are mapped to the operating system's priority values.

See Also

Prioritizing Thread Work


Used to indicate the nature and importance of work to the system. Work with higher quality of service classes receive more resources than work with lower quality of service classes whenever there is resource contention.

+ threadPriority

Returns the current thread’s priority.


The receiver’s priority

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