“The 64-bit Apple chip hit us in the gut.”

via John Gruber. Dan Lyons:

“The 64-bit Apple chip hit us in the gut,” says the Qualcomm employee. “Not just us, but everyone, really. We were slack-jawed, and stunned, and unprepared. It’s not that big a performance difference right now, since most current software won’t benefit. But in Spinal Tap terms it’s like, 32 more, and now everyone wants it.”

The “It’s not that big a performance difference right now…” is inaccurate. Mike Ash, again via John Gruber, points to huge improvements in object creation and destruction speeds in 64-bit mode versus 32-bit mode:

Adding it all together, it’s a pretty big win. My casual benchmarking indicates that basic object creation and destruction takes about 380ns on a 5S running in 32-bit mode, while it’s only about 200ns when running in 64-bit mode. If any instance of the class has ever had a weak reference and an associated object set, the 32-bit time rises to about 480ns, while the 64-bit time remains around 200ns for any instances that were not themselves the target.

In short, the improvements to Apple’s runtime make it so that object allocation in 64-bit mode costs only 40-50% of what it does in 32-bit mode. If your app creates and destroys a lot of objects, that’s a big deal.

I’m not a programmer, but I take this to mean iOS apps that take advantage of the A7 CPU’s 64-bit architecture are faster, now.