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My comment from a week ago: "What would keep Apple from shipping machines with both ARM and Intel CPUs in them? The ARM CPU would run the OS and decide when to

My comment from a week ago: "What would keep Apple from shipping machines with both ARM and Intel CPUs in them? The ARM CPU would run the OS and decide when to ship jobs over to the Intel CPU. I can’t imagine that the home-grown ARM CPU would add much to the total price of the computer." https://news.ycombinator.com/item?id=23530084 https://news.ycombinator.com/item?id=23530084

bhouston 6y ago
It is a lot of work and now you have to buy two CPUs. No cost savings, possibly more power usage in worst case, and maybe even thicker computers. It would restrict it so you can never remove the Intel CPU. It is best to just emulate the Intel CPU for a while until everyone ports their code across.
valuearb 6y ago
Dual CPUs never made any sense. That’s why they are doing emulation and binary conversion. Maybe Apple adds the i86 instruction set as a module in their SOCs, but they aren’t paying intel CPU prices on their ARM Macs.
- snowwrestler 6y ago
  Did I misinterpret today? Didn't Apple just release a machine with ARM and Intel?
  - monocasa 6y ago
    It's an ARM only Developer Kit.
    - snowwrestler 6y ago
      Ah. I saw references to "dual architecture" online but looks like that means Apple will be releasing new Intel machines even as they are encouraging everyone to port their apps to ARM. The "dual" part just means two different lines of machines that will be sold contemporaneously for a little while, not two architectures inside one machine. Oh well, I got excited for a minute there.
  - freehunter 6y ago
    It’s an ARM chip that can run x86 software using translation tools (Rosetta).
q3k 6y ago
This level of asymmetric processing is very difficult to achieve, at nearly every possible level, from part sourcing, through hardware design, firmware, software to user experience.
- snowwrestler 6y ago
  Which was why I thought Apple might blow everyone away by doing it. But I was obviously wrong.
Symmetry 6y ago
Well, in theory both AMD and ARM use MOESI so it's not as crazy as it would be with Intel's MESIF. But that's a really scary rabbit hole to be going down and I'd be terrified of memory permissions attacks striking at the boundary there. So probably not worth the risk unless each processor gets its own pool of RAM. https://en.wikipedia.org/wiki/MOESI_protocol https://en.wikipedia.org/wiki/MOESI_protocol

bhouston 6y ago

It is a lot of work and now you have to buy two CPUs. No cost savings, possibly more power usage in worst case, and maybe even thicker computers. It would restrict it so you can never remove the Intel CPU. It is best to just emulate the Intel CPU for a while until everyone ports their code across.

valuearb 6y ago

Dual CPUs never made any sense. That’s why they are doing emulation and binary conversion. Maybe Apple adds the i86 instruction set as a module in their SOCs, but they aren’t paying intel CPU prices on their ARM Macs.

snowwrestler 6y ago
Did I misinterpret today? Didn't Apple just release a machine with ARM and Intel?
- monocasa 6y ago
  It's an ARM only Developer Kit.
  - snowwrestler 6y ago
    Ah. I saw references to "dual architecture" online but looks like that means Apple will be releasing new Intel machines even as they are encouraging everyone to port their apps to ARM. The "dual" part just means two different lines of machines that will be sold contemporaneously for a little while, not two architectures inside one machine. Oh well, I got excited for a minute there.
- freehunter 6y ago
  It’s an ARM chip that can run x86 software using translation tools (Rosetta).

q3k 6y ago

This level of asymmetric processing is very difficult to achieve, at nearly every possible level, from part sourcing, through hardware design, firmware, software to user experience.

snowwrestler 6y ago
Which was why I thought Apple might blow everyone away by doing it. But I was obviously wrong.

Symmetry 6y ago

Well, in theory both AMD and ARM use MOESI so it's not as crazy as it would be with Intel's MESIF. But that's a really scary rabbit hole to be going down and I'd be terrified of memory permissions attacks striking at the boundary there. So probably not worth the risk unless each processor gets its own pool of RAM. https://en.wikipedia.org/wiki/MOESI_protocol https://en.wikipedia.org/wiki/MOESI_protocol