[objc explain]: Selector uniquing in the dyld shared cache (2009-09-01 2:10 AM) Mac OS X Snow Leopard cuts in half the launch-time overhead of starting the Objective-C runtime, and simultaneously saves a few hundred KB of memory per app. This comes for free to every app, courtesy of one of the few pieces of Mac OS X that lives below even the Objective-C runtime: dyld. dyld and the shared cache dyl

