Le 1 nov. 2013 à 08:38, Gerriet M. Denkmann <gerr...@mdenkmann.de> a écrit :
> Messing with an iPhone app (iOS 7.0.3) Release build on Xcode Version 5.0.1 > (5A2053) I noticed that by switching Arc off in two crucial files the speed > of some operation almost doubled. > > So: are there any rules of thumb what to do and what not to do to avoid an > Arc slowdown? > > Or: are there situations in which Arc is better not used? Yes, when profiling tells you it is in a hot path. The compiler is conservative and anytime it has some doubt, it will retain/release an object. If profiling shows some that code where you now it is safe to avoid this additional retain/release is hot, you can help the compiler by using __unsafe_unretain to annotate the managed variable. -- Jean-Daniel _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
