As of April 27th, 2021, it looks like your emulators may have broken again for the same reason as mine did. According to this post on Stack Overflow, the issue appears to be chronic. Looking through the internet I have found this thread on the apple developer website explaining code signatures for Mac OS.VM.Your eyes do not deceive you - this is QEMU running Tiger with full virtualization on the Talos II. Configure VM acceleration on Windows. / Sdk /emulator/emulator -accel-check accel: 0 KVM (version 12) is installed and usable.Qemu-kvm understands a large number of options. At that price however, it should include. It is sad because it was managing 2 screens, and construction quality was looking top notch. Bottom of the line, better have a KVM that takes care of it, as it should be. You can find DP EDID Emulators for about 77US or HDMI about 42US EACH. I've just turned my POWER9 into a G4.Eithe the KVM has it or we can purchase it (I would need 4).With some minimal tweaks to KVM-PR, I was able to coax Tiger to start up under virtualization, increasing the apparent CPU speed to over 2GHz. That means you'd have to run your Mac operating systems under pure emulation, which eked out something equivalent to a 1GHz G4 in System Profiler but was still a drag. If you do not supply any options, default values are used, and you need to supply the path to a disk image to be run.Recall last entry that there was a problem using virtualization to run Power Mac operating systems on the T2 because the necessary KVM module, KVM-PR, doesn't load on bare-metal POWER9 systems (the T2 is PowerNV, so it's bare-metal).
Kvm Emulator Code Signatures ForPOWER8 and earlier reduce this cost with the translation lookaside buffer (TLB), used to cache a PTE once it's found. If it's there, it continues, or else it sends a page fault to the operating system to map the memory.The first problem is that the format of HPTEs changed slightly in POWER9, so this needs to be accommodated if the host CPU does lookups of its own (it does in KVM-HV, but this was already converted for the new POWER9 and thus works already).The bigger problem, though, is that hash tables can be complex to manage and in the worst case could require a lot of searches to map a page. The processor then checks those 16 entries for a match. The process in a simplified fashion is thus: given a virtual address, the processor translates it into a key for that block of memory using the segment lookaside buffer (SLB), and then hashes that key and part of the address to narrow it down to two page table entry groups (PTEGs), each containing eight PTEs. To turn a virtual address into an actual real address, PowerPC and POWER processors prior to POWER9 exclusively used a hash table of page table entries (PTEs or HPTEs, depending on who's writing) to find the correct location in memory. Maximum effort.The issue on POWER9 is actually a little more complex than I described it (thanks to Paul Mackerras at IBM OzLabs for pointing me in the right direction), so let me give you a little background first. ![]() For the second baseline, I'll use my trusty Quad G5, but I left it in Reduced power mode since that's how I normally run it. That gets a fairly weak 580 Geekbench (Geekbench 2.2 on 10.4, integer 693, floating point 581, memory 500, stream 347). First, my trusty backup workstation, the 1GHz iMac G4: It's not very fast and it has no L3 cache, which makes it worse, but the arm is great, the form-factor has never been equaled, I love the screen and it fits very well on a desk. And here we are.(*)Anyway, you lot will be wanting the Geekbench numbers, won't you? Such a competitive bunch, always demanding to know the score. As it turns out, the first problem actually isn't a problem for booting OS X on KVM once radix mode is off, assuming you hack the KVM-PR kernel module to handle a couple extra interrupt types and remove the lockout on POWER9. That gets around the second problem. Likewise, the poor showing for the standard library memory work might be syscall overhead, which is plausible, but that doesn't explain why a copy is faster than a simple write. I will note for the record that some of the numbers seem a bit suspect although there may well be a performance delta between image compression and decompression, it shouldn't be this different and it would more likely be in the other direction. But still, this is a decent showing for the T2 in "Mac mode" given all the other overhead that's going on, and the T2 is doing that while running Firefox with a buttload of tabs and lots of Terminal sessions and I think I was playing a movie or something in the background. Again, do remember that the G5 was intentionally being run gimped here: if it were going full blast, it would have blown the World's Baddest Power Mac G4 out of the water. That's into the G5's range, at least with math performance, and the G5 did it with four threads while this poor thing only has one (QEMU's Power Mac emulation does not yet support SMP, even with KVM). Even with my hacked KVM-PR, a raw disk image and rebuilding a stripped down QEMU with -O3 -mcpu=power9, disk and network throughput are quite slow and it's even worse if there are lots of graphics updates occurring simultaneously, such as installing Mac OS X with the on-screen Aqua progress bar. Also, I/O performance in QEMU regardless of KVM is dismal. It is not sufficient to boot Mac OS 9 that causes the kernel module to err out with a failure in memory mapped I/O, which is probably because it actually does need the first problem to be fixed, and similarly I would expect Linux and NetBSD won't be happy either for the same reason (let alone nesting KVM-PR within them, which is allowed and even supported). Better than cc cleaner for a macAnother unrelated annoyance is that QEMU's emulated video card doesn't offer 16:9 resolutions, which is inconvenient on this 1920x1080 display. For that reason I let Software Update run in emulated mode so that if a bug occurred during the installation, it wouldn't completely hose everything and make the disk image unbootable (which did, in fact, happen the first time I tried to upgrade to 10.4.11). More ominously I'll get occasional soft lockouts in the kernel (though everything keeps running), usually if it's doing heavy disk access, and it acts very strangely with stuff that messes with the hardware such as system updates. This time, TenFourFox crashed the entire emulator (which exited with an illegal instruction fault). At that point I assumed it was a bug in KVM-PR and tried starting it in pure emulation. So I tried starting it in safe mode on the assumption the JIT was making it unsteady, which seemed to work when it gave me the safe mode window, but then when I tried to start the full browser still crashed with an illegal instruction fault (in a different place). I installed the G3 version and tried running it in QEMU+KVM-PR, and TenFourFox crashed with an illegal instruction fault. For example, you'll notice there are no screenshots of the T2 running TenFourFox. ![]() ![]() I gave it an entry in /usr/share/applications so that I could directly view images from the GNOME file manager. Eventually I hacked FreePV into building and that substitutes nicely as well.
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