Dictionary cache thread safety
In a message list screen, each cell downloads its profile image asynchronously and caches it in a [String: UIImage] dictionary. With several threads reading and writing at once, it crashes now and then. Why does it crash?
ConcurrencyShort answerBasics
This code gets called from several threads, and count comes out lower than expected. Can …
#lock #actor
CS fundamentals and algorithmsShort answerAdvanced
You need to write an in-memory image cache with LRU eviction yourself. Which data structu…
#dictionary #nscache
Memory and ARCMultiple choiceAdvanced
In Objective-C you declare @property (atomic) int a; and run self.a = self.a + 1 a combin…
#thread-safety #lock
NetworkingMultiple choiceBasics
Select all the statements that correctly describe how NSCache differs from Dictionary.
#dictionary #nscache