iOS的多核编程和内存管理

http://anxonli.iteye.com/blog/1097777


http://www.dreamingwish.com/dream-2012/of-of-of-of-gcd-introduced-1-basic-concepts-in-and-the-dispatch-queue.html


https://developer.apple.com/library/ios/#documentation/Performance/Reference/GCD_libdispatch_Ref/Reference/reference.html#//apple_ref/c/func/dispatch_release


https://developer.apple.com/library/ios/#documentation/General/Conceptual/ConcurrencyProgrammingGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40008091-CH1-SW1