AFNetworking/AFNetworking — pull request #469 by mtuzzolo (2012-08-21 17:34:33+00:00)
Title: Faster calculation of the count of finished operations in a queue.

This works around a performance issue with NSPredicate that arises when canceling queues with a large number of operations. Since the progress blocks are generally executed on the main thread, the UI can be blocked for several seconds when large queues are cancelled. Fast Enumeration performs much better, completing in roughly .0004s for ~1700 operations vs .0090s when using filteredArrayUsingPredicate.