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> They design chips and market them. They do both things like no other company on this planet. Latter for sure, former not so much. Apple is not designing its

> They design chips and market them. They do both things like no other company on this planet. Latter for sure, former not so much. Apple is not designing its own CPUs (but ARM does) nor they are physically manufacturing or improving the silicon process (but TSMC does), they build SoCs like many other companies out there. This means that they can't make an advantage over the competitors by: 1. Making the silicon process more advanced 2. Improving CPU microarchitecture 3. Improving CPU instruction pipeline 4. Improving CPU branch prediction or OOO execution 5. Making the TLB page-walker algorithms more efficient 6. Making better cache-coherency protocols 7. Implementing their own bus interconnect which is faster than others 8. Designing better RAM modules 9. Etc. etc. (I could go on and on but I guess the point is visible) What Apple can do to make a difference is that they can fine tune the SoC microarchitectural details but hardly anything else. By looking at the specs of M1's, the biggest outliers with respect to other chips of the same or similar class currently existing on the market are: 1. RAM and CPUs are physically co-located on the same die 2. RAM is advanced to (LP)DDR5 3. CPU caches are massive (L1, L2 and TLB) 4. There's a separate cluster of CPUs for low-power mode execution First three things from the list is what is making M1's so fast, and especially the third point. Enlarging CPU caches has been done by the server CPUs like forever and which is the reason why quite old (2014) 2x Xeon system can eat AMD Ryzen 9 5950X for breakfast in some of the multicore workloads I ran (and I mean substantially). Last thing from the list above is what is making this chip more power efficient and this technique is as old as the moment when big.LITTLE was introduced in 2011. In nowadays ARM chips it is known as DynamIQ but the concept is the same: conserving energy by running less power hungry CPUs when workload does not require the full power (which in average user is most of the time).

acdha 5y ago
> Apple is not designing its own CPUs (but ARM does) Do you have any evidence supporting this? If you were right, it would seem odd that Apple has consistently delivered significantly better performance, often by multiple product generations, than other ARM licensees since the launch of the A8 in 2014 if ARM was doing all of the real work. Similarly, it seems like they could have saved a ton of money not hiring chip architects if they didn't have anything for them to work on.
kuhsaft 5y ago
> Apple is not designing its own CPUs (but ARM does) Apple IS designing its own CPUs. They have been designing their own CPUs since their A4 processor. Apple has an Architecture License with ARM [1]. Other companies with the same license include Qualcomm, Samsung, Nvidia, and Broadcom. These licensees have full architectural freedom with the cores as long as they are ARM ISA compatible. For example, Apple has added custom instructions in their M1 processor [2]. So, an Apple ARM processor core is different from a Samsung ARM core is different from a Qualcomm ARM core. [1] https://www.anandtech.com/show/7112/the-arm-diaries-part-1-how-arms-business-model-works/3 https://www.anandtech.com/show/7112/the-arm-diaries-part-1-h... [2] https://news.ycombinator.com/item?id=25559145 https://news.ycombinator.com/item?id=25559145
- marcan_42 5y ago
  > as long as they are ARM ISA compatible. And apparently in Apple's case, they get to be a little bit incompatible (no nVHE mode, crazy custom ISA extensions, ...) Which is also obvious proof that they're their own designs, because literally nobody else could or would implement the same Apple-proprietary ISA extensions. Here, we use some of the custom instructions in m1n1: https://github.com/AsahiLinux/m1n1/blob/main/src/gxf_asm.S#L7 https://github.com/AsahiLinux/m1n1/blob/main/src/gxf_asm.S#L... That won't work on any non-Apple core.
  - masklinn 5y ago
    > literally nobody else could or would implement the same Apple-proprietary ISA extensions. That is maybe a little excessive, technically they could probably pay an other architecture license holder to do it for them.
    - marcan_42 5y ago
      No, because the architecture license doesn't allow it. Apple got special treatment here.
      - masklinn 5y ago
hedgehog 5y ago
Almost all of this is inaccurate. You can read about their silicon program in pretty much any trade magazine for details but for example: their main cores have been in-house designs for about a decade, RAM is on-package not on-die, that is probably only a moderate perf win in itself, they have been contributing to and extending the ISA for many years, etc. What the Apple chips do appear to be is a successful application of the "lead bullets" approach to good engineering. If you compare to Zen 2 it's clear that Apple's designs are not really incomparably better than peers, but they are excellent. With the advantage of better software support and a better manufacturing process than other mobile CPUs they perform really well. They don't directly compete with CPU vendors but hopefully their new products light the fire under their PC counterparts to build better products. I sure hate feeling trapped in their super buggy software ecosystem.
- GeekyBear 5y ago
  I think one thing that has been fairly unique in the industry is that Apple has been willing to throw silicon die area at a problem. For example, their cache sizes are massive in comparison to anything else in the consumer space. If you sell chips to device manufacturers for a living, increasing die size cuts directly into how much you make per wafer. When you sell devices containing your own custom chips, your profit margin does not depend on the cost of fabbing that chip alone. As a bonus, when everyone else is trying to make a smaller die and cranks up the clocks for performance, you are hugely more power efficient (without giving up performance) when you throw die size at an extra wide instruction decode with a ton of execution units running at a much slower clock speed and have huge reorder buffers so you can track more instructions in flight. https://www.anandtech.com/show/16226/apple-silicon-m1-a14-deep-dive/2 https://www.anandtech.com/show/16226/apple-silicon-m1-a14-de...
  - hedgehog 5y ago
    It's an interesting hypothesis, I'm not sure how true this is. The newer Ryzen 3 and upcoming Alder Lake products are between M1 and M1 Pro sized, and they all have similar total amounts of cache. Arguably by using both a bit more area and a more advanced process Apple has a much higher transistor budget to work with, but throwing more transistors at the problem doesn't necessarily help power efficiency. The one area where they have a really decisive advantage is their ability to synchronize OS development with hardware roadmap, then force developers to play along (via app store rules).

acdha 5y ago

> Apple is not designing its own CPUs (but ARM does) Do you have any evidence supporting this? If you were right, it would seem odd that Apple has consistently delivered significantly better performance, often by multiple product generations, than other ARM licensees since the launch of the A8 in 2014 if ARM was doing all of the real work. Similarly, it seems like they could have saved a ton of money not hiring chip architects if they didn't have anything for them to work on.

kuhsaft 5y ago

> Apple is not designing its own CPUs (but ARM does) Apple IS designing its own CPUs. They have been designing their own CPUs since their A4 processor. Apple has an Architecture License with ARM [1]. Other companies with the same license include Qualcomm, Samsung, Nvidia, and Broadcom. These licensees have full architectural freedom with the cores as long as they are ARM ISA compatible. For example, Apple has added custom instructions in their M1 processor [2]. So, an Apple ARM processor core is different from a Samsung ARM core is different from a Qualcomm ARM core. [1] https://www.anandtech.com/show/7112/the-arm-diaries-part-1-how-arms-business-model-works/3 https://www.anandtech.com/show/7112/the-arm-diaries-part-1-h... [2] https://news.ycombinator.com/item?id=25559145 https://news.ycombinator.com/item?id=25559145

marcan_42 5y ago
> as long as they are ARM ISA compatible. And apparently in Apple's case, they get to be a little bit incompatible (no nVHE mode, crazy custom ISA extensions, ...) Which is also obvious proof that they're their own designs, because literally nobody else could or would implement the same Apple-proprietary ISA extensions. Here, we use some of the custom instructions in m1n1: https://github.com/AsahiLinux/m1n1/blob/main/src/gxf_asm.S#L7 https://github.com/AsahiLinux/m1n1/blob/main/src/gxf_asm.S#L... That won't work on any non-Apple core.
- masklinn 5y ago
  > literally nobody else could or would implement the same Apple-proprietary ISA extensions. That is maybe a little excessive, technically they could probably pay an other architecture license holder to do it for them.
  - marcan_42 5y ago
    No, because the architecture license doesn't allow it. Apple got special treatment here.
    - masklinn 5y ago

hedgehog 5y ago

Almost all of this is inaccurate. You can read about their silicon program in pretty much any trade magazine for details but for example: their main cores have been in-house designs for about a decade, RAM is on-package not on-die, that is probably only a moderate perf win in itself, they have been contributing to and extending the ISA for many years, etc. What the Apple chips do appear to be is a successful application of the "lead bullets" approach to good engineering. If you compare to Zen 2 it's clear that Apple's designs are not really incomparably better than peers, but they are excellent. With the advantage of better software support and a better manufacturing process than other mobile CPUs they perform really well. They don't directly compete with CPU vendors but hopefully their new products light the fire under their PC counterparts to build better products. I sure hate feeling trapped in their super buggy software ecosystem.

GeekyBear 5y ago
I think one thing that has been fairly unique in the industry is that Apple has been willing to throw silicon die area at a problem. For example, their cache sizes are massive in comparison to anything else in the consumer space. If you sell chips to device manufacturers for a living, increasing die size cuts directly into how much you make per wafer. When you sell devices containing your own custom chips, your profit margin does not depend on the cost of fabbing that chip alone. As a bonus, when everyone else is trying to make a smaller die and cranks up the clocks for performance, you are hugely more power efficient (without giving up performance) when you throw die size at an extra wide instruction decode with a ton of execution units running at a much slower clock speed and have huge reorder buffers so you can track more instructions in flight. https://www.anandtech.com/show/16226/apple-silicon-m1-a14-deep-dive/2 https://www.anandtech.com/show/16226/apple-silicon-m1-a14-de...
- hedgehog 5y ago
  It's an interesting hypothesis, I'm not sure how true this is. The newer Ryzen 3 and upcoming Alder Lake products are between M1 and M1 Pro sized, and they all have similar total amounts of cache. Arguably by using both a bit more area and a more advanced process Apple has a much higher transistor budget to work with, but throwing more transistors at the problem doesn't necessarily help power efficiency. The one area where they have a really decisive advantage is their ability to synchronize OS development with hardware roadmap, then force developers to play along (via app store rules).