What performance penalties arise while using method swizzling in Objective-C?
Which, if any, compiler optimisations are defeated with message swizzling?
Asked
Active
Viewed 386 times
8
O. Jones
- 103,626
- 17
- 118
- 172
Ilea Cristian
- 5,741
- 1
- 23
- 37
-
7This question can not generate opinion based answers. An individual that knows compiler stuff can answer it with facts. @pjs and co, stop hunting points. – Tudor Luca Jul 22 '15 at 10:20
-
4I would like to know the answer to this question, too. – Andra Todorescu Jul 22 '15 at 10:22
1 Answers
5
Swizzling makes the Objective-C runtime flush its method caches. If you do all your swizzling as early as possible in your program, this will probably have no noticeable impact.
The compiler can't do much to optimize method calls because Objective-C allows any method to be overridden, even at run time (as with swizzling). So you've already paid the performance price of swizzling whether you use it or not.
rob mayoff
- 375,296
- 67
- 796
- 848