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The article gets into some technical aspects, but focuses specifically on A11->A12 changes. Mostly, A-series chips have enormous L1 cache, great cache hierarch

The article gets into some technical aspects, but focuses specifically on A11->A12 changes. Mostly, A-series chips have enormous L1 cache, great cache hierarchy and management, and very low memory latency. A12 specifically seems to have included an almost total redesign of the cache hierarchy. I'm sure there are many more reasons their designs significantly outperform competitors, but I've not seen any more publicly available analysis.

aw1621107 8y ago
> Mostly, A-series chips have enormous L1 cache, great cache hierarchy and management, and very low memory latency. Has this always been the case compared to contemporary Qualcomm/Exynos/etc. SoCs? Not implying your statement is wrong here; all I know is that the A-series chips have had a big performance advantage for a while now and I haven't read more detailed analyses in the past that may have given hints as to why. Also, how difficult is cache hierarchy/management to get right? For something as fundamental to good performance these days as cache, I would have expected the major players to be on more or less the same playing field.
- baybal2 8y ago
  They are, but sram takes space, and thus money. Apple optimises chip performance Others optimize chip size
  - aw1621107 8y ago
    So if one of the other SoC manufacturers decided to match Apple's cache sizes, they should get similar performance? Or is that oversimplifying?
    - nicoburns 8y ago
      I think part of it is that Apple aquired a very smart team of chip designers. That, and they probably give them a bigger budget probably explains most of the difference. Also, apple have pursued 2 (very) fast cores whereas other chips often have 4. Of course, this iteration apple have beaten almost everyone else to 7nm, so the difference is much more dramatic.
      - baybal2 8y ago
        >I think part of it is that Apple aquired a very smart team of chip designers. Yes, PA micro was the place where the "last of Mahicans" of US chip industry were. >Also, apple have pursued 2 (very) fast cores whereas other chips often have 4. Yes, because people into app development are as web developers, and the word "mutex" gives most of them a panic attack. Android style java should've been more multi-threading friendly, but that does nothing about people not utilising them. > this iteration apple have beaten almost everyone else to 7nm, so the difference is much more dramatic. Yes. I remember how Mediatek beaten Apple to 10nm thanks to them being a Taiwanese company, but nevertheless "ruined it all" with their helio x30's design being designed with more marketing considerations than engineering ones. Their marketing guys couldn't wait to announce "hey we have 2 more cores than you Qualcomm!"
- gniv 8y ago
  > Has this always been the case compared to contemporary Qualcomm/Exynos/etc. SoCs? Yes, that's my understanding. I've seen this discussion last year and the year before. And every time the answer seems to be caches. Cache memory is expensive. Apple seems willing to pay more for the SoC in order to have an overall experience that lets them get away with the high prices. From what I read, Qualcomm would not be able to sell at volume an equivalently performant SoC.

aw1621107 8y ago

> Mostly, A-series chips have enormous L1 cache, great cache hierarchy and management, and very low memory latency. Has this always been the case compared to contemporary Qualcomm/Exynos/etc. SoCs? Not implying your statement is wrong here; all I know is that the A-series chips have had a big performance advantage for a while now and I haven't read more detailed analyses in the past that may have given hints as to why. Also, how difficult is cache hierarchy/management to get right? For something as fundamental to good performance these days as cache, I would have expected the major players to be on more or less the same playing field.

baybal2 8y ago
They are, but sram takes space, and thus money. Apple optimises chip performance Others optimize chip size
- aw1621107 8y ago
  So if one of the other SoC manufacturers decided to match Apple's cache sizes, they should get similar performance? Or is that oversimplifying?
  - nicoburns 8y ago
    I think part of it is that Apple aquired a very smart team of chip designers. That, and they probably give them a bigger budget probably explains most of the difference. Also, apple have pursued 2 (very) fast cores whereas other chips often have 4. Of course, this iteration apple have beaten almost everyone else to 7nm, so the difference is much more dramatic.
    - baybal2 8y ago
      >I think part of it is that Apple aquired a very smart team of chip designers. Yes, PA micro was the place where the "last of Mahicans" of US chip industry were. >Also, apple have pursued 2 (very) fast cores whereas other chips often have 4. Yes, because people into app development are as web developers, and the word "mutex" gives most of them a panic attack. Android style java should've been more multi-threading friendly, but that does nothing about people not utilising them. > this iteration apple have beaten almost everyone else to 7nm, so the difference is much more dramatic. Yes. I remember how Mediatek beaten Apple to 10nm thanks to them being a Taiwanese company, but nevertheless "ruined it all" with their helio x30's design being designed with more marketing considerations than engineering ones. Their marketing guys couldn't wait to announce "hey we have 2 more cores than you Qualcomm!"
gniv 8y ago
> Has this always been the case compared to contemporary Qualcomm/Exynos/etc. SoCs? Yes, that's my understanding. I've seen this discussion last year and the year before. And every time the answer seems to be caches. Cache memory is expensive. Apple seems willing to pay more for the SoC in order to have an overall experience that lets them get away with the high prices. From what I read, Qualcomm would not be able to sell at volume an equivalently performant SoC.