Running Snow Leopard on a PowerPC Mac

foxlet

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During the PowerPC challenge a few weeks ago, I was experimenting with running the Snow Leopard kernel via emulation (QEMU) on a PowerPC system. I've never seen much progress in terms of that, so I thought of documenting it at this point.

Indeed, it is possible to boot the kernel up to a point, although in this instance the system crashes, possibly due to the emulated clock being too slow/variable (it is a rather old PowerBook G4 Ti, which makes sense). The kernel is based on a modified kernel (by nawcom) that includes a needed SSE3 emulator.



In essence, it might be possible to actually reach the desktop with a more powerful PowerPC Mac (the image was tested on a 2009 Core2Duo Mac with an identical QEMU build, which ran Snow Leopard fine, albeit slowly).

Case in point, I did technically run the Snow Leopard kernel on a PowerPC Mac. :)
 

AphoticD

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Case in point, I did technically run the Snow Leopard kernel on a PowerPC Mac. :)
Well done. Just curiously, what version of Qemu are you using? 2.4.0 is the latest I have been able to build under OS X. Whereas Linux on the same PowerPC (G5) hardware can build and run the current 2.9.0 release.
 

foxlet

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Well done. Just curiously, what version of Qemu are you using? 2.4.0 is the latest I have been able to build under OS X. Whereas Linux on the same PowerPC (G5) hardware can build and run the current 2.9.0 release.
I'm using the latest version of QEMU (2.9.0) from source. They all compile fine under OS X on my end.
 

LightBulbFun

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I think he is referring to the QEMU version used on your Tibook :)

for the record you should not need to use a kernel with an SSE3 emulator, QEMU is perfectly capable of emulating a Core Duo or Core 2 Duo and booting Snow leopard, you can also specify an SMC in QEMU and avoid the need for FakeSMC

going by the bad colours, I assume your using quite an old build that uses SDL?
 
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foxlet

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I think he is referring to the QEMU version used on your Tibook :)

for the record you should not need to use a kernel with an SSE3 emulator, QEMU is perfectly capable of emulating a Core Duo or Core 2 Duo and booting Snow leopard, you can also specify an SMC in QEMU and avoid the need for FakeSMC

going by the bad colours, I assume your using quite an old build that uses SDL?
Yes, the regular kernel does also work, but on the PowerBook G4 it was too crash-prone (more often not even loading the kernel and switching into text mode, just crashing back to firmware). QEMU does indeed support SMC emulation, but the image I was working with already included FakeSMC, so there was no real harm in keeping it.

As noted earlier, those screenshots are somewhat old now, they were running on 2.2.1 but it has since been updated.
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I tried messing with emulating Windows on a PPC, I didn't have much luck but I'm shocked to see that you were able to make Windows 8's installer load!!
A normal installation of Windows 8 runs, too!
 

amagichnich

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Feb 3, 2017
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I always loved the idea of SL for PPC but honestly what would be the point in it? SL is Leopard but the core system parts rewritten for 64bit multi-core intel processors. Rewriting it now for PPCs (64bit multicore) would in some scenarios boost up the system a bit, but a) not very much systems could apply it and b) not many of these would really benefit of it. That's my opinion, correct me if I'm wrong ;)
 

AmazingHenry

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I always loved the idea of SL for PPC but honestly what would be the point in it? SL is Leopard but the core system parts rewritten for 64bit multi-core intel processors. Rewriting it now for PPCs (64bit multicore) would in some scenarios boost up the system a bit, but a) not very much systems could apply it and b) not many of these would really benefit of it. That's my opinion, correct me if I'm wrong ;)
Yeah, only the 64 bit G5 machines could use it.
 
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Dronecatcher

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Can anyone actually quantify the performance difference between Leopard and Snow Leopard on an Intel machine? It's been so long, I can't remember.

EDIT: Sorry, meant to post this in the Transforming Leopard into Snow Leopard thread.
 
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AmazingHenry

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Can anyone actually quantify the performance difference between Leopard and Snow Leopard on an Intel machine? It's been so long, I can't remember.

EDIT: Sorry, meant to post this in the Transforming Leopard into Snow Leopard thread.
It's a pretty big difference on a C2D. Probably not as big on the Core Duo and Core Solo processors.
 

bunnspecial

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x86 emulation on PowerPC results in a huge performance cost. Not likely to be good for anything more than proof of concept and running some very light applications.
Win2K in VPC is okay. My experience is that even on a Quad, XP is too much. Yes, I've done it, and at the time did it for practical reasons(specific software that I needed on the Quad, which was my main desktop then).
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It's a pretty big difference on a C2D. Probably not as big on the Core Duo and Core Solo processors.
Unless you are running 64 bit applications, the differences between CD and C2Ds is entirely down to clock speed(and other things like cache amount).
 

z970mp

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Win2K in VPC is okay. My experience is that even on a Quad, XP is too much. Yes, I've done it, and at the time did it for practical reasons(specific software that I needed on the Quad, which was my main desktop then).
[doublepost=1501271074][/doublepost]

Unless you are running 64 bit applications, the differences between CD and C2Ds is entirely down to clock speed(and other things like cache amount).
I get the feeling that it's not quite the G5 isn't able to handle XP, I think it's more to do with the fact that Virtual PC has a limit to how much CPU and RAM you can give the virtualization. I had 4GB of RAM and it only allowed 512MB through. It's infuriating.
 

128keaton

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I get the feeling that it's not quite the G5 isn't able to handle XP, I think it's more to do with the fact that Virtual PC has a limit to how much CPU and RAM you can give the virtualization. I had 4GB of RAM and it only allowed 512MB through. It's infuriating.
512MB of RAM is enough to run XP on.
 

Dronecatcher

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I get the feeling that it's not quite the G5 isn't able to handle XP, I think it's more to do with the fact that Virtual PC has a limit to how much CPU and RAM you can give the virtualization.
True. VPC/Win2000 ran as well on my 1.33 Powerbook as it did on my Quad. VPC wasn't really improved much v5 onwards.
 

eyoungren

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Win2K in VPC is okay. My experience is that even on a Quad, XP is too much. Yes, I've done it, and at the time did it for practical reasons(specific software that I needed on the Quad, which was my main desktop then).
I've had some success with running XP and 7 on VPC. Of course, my Quad is maxed out with ram, but that doesn't really impact VPC 7 as you can only assign a certain amount.

I'm using a stripped down version of XP though (available in places on the web) and I have all the eye candy crap off with 7.

Mainly just using for low impact games.
 
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