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They did say something fairly concrete: they said it's "twice as fast" as the A6 in "CPU performance." This has nothing to do with virtual address size and poin
by jrk 13y ago
They did say something fairly concrete: they said it's "twice as fast" as the A6 in "CPU performance." This has nothing to do with virtual address size and pointer width (which only have a negative impact on relative performance, due to instruction encoding and pointer data bandwidth overhead), fairly little to do with ARMv8 vs. ARMv7 (which we know to make only a fairly modest difference—double the NEON register count is probably the biggest bump for interesting benchmarks), and a great deal to do with a combination of microarchitectural improvement and clock speed increases (early data trickling out strongly suggest it is 1.7Ghz in the 5s, vs. the Swift 1 cores' 1.3Ghz).
So yes, by saying that it's "2x faster," Apple actually did fairly strongly say that it includes major microarchitectural improvements over the core design in the A6, much like we know there to be between the Cortex A15 and A57.
- ajross 13y agoShrug. My brain hears that kind of language in the same way that it heard "the G4 with Altivec is a supercomputer on your desk and blows away the competition" when of course it was a near-uniformly inferior CPU to its competitors. I'm sure it's faster. I don't believe 2x on general code at all. I half suspect they really mean 2x as fast on some crypto benchmark that can leverage wider word widths or something similarly inane. But I'm not going to claim that on a forum because, as mentioned, they haven't actually told us anything interesting. We're seriously supposed to have an informed discussion about CPU architecture based on marketing copy? No.
- rayiner 13y agoApple has always been cagey about its ARM CPUs. What we know about A6 was almost all reverse engineered. A lot is still conjecture.
- MaysonL 13y agoUP TO 2x faster CPU and GPU performances.