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A comment on Apple announces it will switch to its own processors for future Macs. Parent comment

Re:Apple announces it will switch to its own processors for ... by nieve on Tuesday June 23, 2020 @05:56AM (#23611831)
I'm somewhat confused by this rhetorical question since the microcode of processor is vastly different than the userspace & kernel of Mac OS. Running an OS bare metal versus in a VM on top of Mac OS are different across a wide array of things. At a minimum performance is lower and less predictable on the VM; you now have two different OS's updates to worry about breakage with on top of their mutual interface (ask anyone who's done serious Linux dev work on a Mac); you have two different sets of security policies to worry about; the low level tools to debug performance in a VM don't have the level of access they do on bare metal; and if you're working with hardware for linux servers & devices in a VM you are going to have to go bare metall sooner or later.

The abstractions are leaky, the VM is not a pristine environment floating on top of some vaguely well-defined architecture. The software in one has two extra layers (VM software & OS) between it and the actual platform and all this is before you start hitting weird corner cases with cpu architecture differences in the layers.

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Re:Apple announces it will switch to its own processors for ... by eecc on Wednesday June 24, 2020 @03:01AM (#23624921)
Hmm, really? Since Windows 10 your desktop runs in a guest domain, while the kernel running the drivers is isolated.

Since about 5 years Apple provides this kit: https://developer.apple.com/documentation/hypervisor Yeah, you got to use the hardware drivers from Apple unless it also supports PCI pass through, not sure but with the current user base I guess nobody would do that anyway.

I expect Apple to eventually run their ring-1 off the T chip, with everything else from a VM abstraction. It’s just the natural evolution of the UEFI approach, and Apple being themselves they’re doing it “their way” without waiting for the crossfire infested industry committees to play along.

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