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PPC emulation near twice as fast on arm.

DearthnVader

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Ryzen 7 1700 3.75 Ghz

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The iPhone FPU score was 63%
 

DearthnVader

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Dec 17, 2015
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Which emulator? UTM?
Yes, UTM.

It will be nice to get some benchmarks from someone with a DTK when they arrive.

I got Windows XP installed in a 32bit VM and Geekbench 2 wasn't good.


No dice on Windows 10 in a x86_64 vm, won't boot the installer all the way, but I can only give it 512mb of ram on my iPhone XR.

I'll try the 32bit ISO and see if that gets me any further.
 
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tevion5

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Wow that's really interesting!

As a comp-sci grad, but by no means a cpu specialist, I reckon this performance boost is partly due to the smaller overhead in emulating Power ISA's reduced instruction set on ARM compared to the very different CISC nature of x86_64?

Probably about 50 big factors at play here but in theory it should be more efficient for one RISC CPU to emulate another kind of RISC CPU, they're both designed to work with short instructions per clock cycle as opposed to x86_64 relying more heavily on specific lengthy instructions that aren't there in PPC.

That said x86 has become a lot more optimised by clock cycle in the last 2 decades and similarly ARM has gained a lot more complex instructions so the difference isn't as severe as it once was.

Would be pretty funny if a side effect of the ARM transition is a better environment for old PPC software.
 
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DearthnVader

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Nice! Do you have any PPC version of macOSX running? I will need this for some old software. 👍
Yes, I ran Tiger, it runs better than it does on x86.

Others have reported that Leopard also works.

Given we are only running on iPhone/iPad, but I assume Qemu will be ready on day one when Apple SoC Macs actually ship. I've run Qemu plenty on an Arm ChromeBook, so really, all we need is Brew to install some of Qemu's dependencies.
 
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Spectrum

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Yes, I ran Tiger, it runs better than it does on x86.

Others have reported that Leopard also works.

Given we are only running on iPhone/iPad, but I assume Qemu will be ready on day one when Apple SoC Macs actually ship. I've run Qemu plenty on an Arm ChromeBook, so really, all we need is Brew to install some of Qemu's dependencies.
In terms of speed, do you mean compared to emulation on an x86 host? How does it compare to virtualising Tiger on x86 host?

May I ask what macOS files are needed? Original disks, or an .iso file? Would doing so officially require the server version?
 
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DearthnVader

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In terms of speed, do you mean compared to emulation on an x86 host? How does it compare to virtualising Tiger on x86 host?

May I ask what macOS files are needed? Original disks, or an .iso file? Would doing so officially require the server version?
Tiger PPC in an emulator is never going to be as fast as Tiger Intel running it a hypervisor( Virtualization ).

According to the old Apple license for OS X, only server was licensed to be run in a hypervisor, but that never stopped anyone.

As far as Qemu-system-ppc, you only need the standard OS X installers. Doesn't run in a hypervisor, but it's not a Mac, so it violates other parts of the software license anyway.
 
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