Lock-free increment range
Five threads each run count += 1 20 times on a shared variable count (initially 0), with no lock. When they've all finished, what range of values can count have? (Assume the increment is three steps, read, add, write, and another thread can cut in between any two steps.)
Pick one
ConcurrencyShort answerBasics
This code gets called from several threads, and count comes out lower than expected. Can …
#race-condition #data-race #lock
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In Objective-C you declare @property (atomic) int a; and run self.a = self.a + 1 a combin…
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ConcurrencyMultiple choiceBasics
Which of the following statements about DispatchSemaphore and mutexes (NSLock, Mutex) are…
#lock
ConcurrencyShort answerAdvanced
How does Thread Sanitizer actually catch data races?
#data-race