objective c - @synchronized or serial dispatch queues -


this question has answer here:

is there performance gain when using serial dispatch queue (assuming high or default priority) on @synchronized blocks serialize access resource. gain, mean difference in overhead due synchronization mechanism itself.

certainly. there's differences in semantics though. @synchronized block uses recursive, exception-safe mutex in side-table. of properties lead additional overhead. dispatch_queue_t extremely light weight (especially when using dispatch_*_f avoid block_copy()), non-recursive, doesn't handle exceptions, , doesn't guarantee particular thread.

personally, think recursive locks bad idea, , exceptions shouldn't caught in cocoa apps, @synchronized has little appeal.


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