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Microsoft says “Prism” translation layer does for Arm PCs what Rosetta did for Macs
(arstechnica.com)
this post was submitted on 20 May 2024
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What Apple did for Macs when switching architectures, though, was to port their own software to the new architecture. Microsoft doesn't even port fucking Minesweeper to ARM.
Another thing they did is add hardware support for the x86 strong memory model to their ARM chips, allowing for efficient emulation. Without this, translated code takes a big performance hit.
Did Qualcomm add something similar to their ARM CPUs ?
They've still got things that haven't changed since about Windows 3.1, like that ODBC dialog window.
Isn't that the point? This new layer is supposed to make it easier to port everything, and they're saying that's what Rosetta did for Apple/Mac.
Translation layers aren't porting
Fair enough, but to the end user it doesn't matter if it works.
Emulation is always slower and eats more battery. Microsoft's laziness is proof they don't care about that hardware, so may just as well buy an iPad Pro instead.
To add to what the other person said, there are some Windows-only games even today that run better on Linux than on Windows (I don't have examples off the top of my head.)
Wine is not CPU emulation.
This is a pretty interesting counter example: https://www.eteknix.com/running-yuzu-on-switch-gives-you-better-performance-than-native-gaming/
But, as others have said, exceptions confirm the rule.
Yuzu can exhibit superior performance because the Switch is rocking the Tegra X1 from 2015. Yuzu absolutely cannot beat the Switch with contemporary hardware and/or comparable power consumption.
But yuzu was running on the switch in that example. So it was beating the switch on contemporary hardware.
Oh yeah, clearly I did not read the article well. Still, it doesn’t mean what you think it does.
First, Yuzu is more of an alternative API implementation than an emulator in this setup. The stock Switch OS and API implementation have been entirely replaced with Linux and the Yuzu implementation of the API. Given recent performance uplifts in the Linux kernel, I’m not surprised that Linux+Yuzu beats the first-party implementation.
Second, the use of the word “emulation” in the above thread is really a misnomer: Rosetta 2, Prism and the like all perform what is called dynamic ISA translation. Yuzu need not perform ISA translation when running on ARM hardware.
I'm also not surprised and I still find it amusing. The ISA translation is something I never actually thought about in emulation
It is always quite amusing to see a billion dollar corporation beaten in its own game :)
More information/context, if you’re curious:
Rosetta 2 in particular isn’t full emulation because the API is the same for both architectures - it is only dynamic ISA translation. I expect that Prism will be slightly closer to full emulation; there is simply no way Microsoft will reimplement all of the legacy Windows APIs on ARM.
WINE is a great example of something that is also not a full emulator, but for the opposite reason: it does not perform any ISA translation or hardware emulation, but rather only syscall (API) translation.
Just like wine is not a windows emulator, this will not be an x86 emulator
Its not laziness, they have lost developers support over time and lets be honest here, Windows 8 arm was roundly laughed out the door. Expectations are now marketing hallucinated by copilot.
This is typical Microsoft “agile”: minimum effort and delivery.
Not porting simple stuff like Minesweeper is definitely laziness on Microsoft's part.
FTFY. There have been some cases where emulation actually outperforms native execution, though these might be, "the exceptions that prove the rule." For example, in the early days of World of Warcraft, it actually ran better on WINE on Linux than natively on Windows.
WINE literally stands for "WINE Is Not an Emulator".
To be fair this is also a translation layer and not an emulator.
Prism is an x86 emulator for ARM. If you think that Prism is "a translation layer and not an emulator", I refer you to the very first word of the second to last paragraph of the submitted article.
That's assuming the writer knows what they're talking about. Last line from the second paragraph:
And first line from the third paragraph.
Certainly more than you because Prism emulates an x86 CPU and WINE doesn't, therefore the WINE comparison is still wrong.
Edit: Please prove the writer wrong.
This article seems to conflate "emulation" and "translation layer". I don't think there is anything that confirms "Prism emulates an x86 CPU", only that it allows for running x86 code on ARM. This does not inherently require emulation as demonstrated by Rosetta 2, which is a translation layer.
WINE doesn't "translate" one CPU architecture to another CPU architecture either, so the WINE comparison is still wrong, no mater if CPU translation is called emulation by you or not. WINE is a wrapper for API calls within the same CPU architecture. That's it.
Wrong again.
"Windows apps are mostly compiled for x86 and they won't run on ARM with bare Wine"
What you linked is an effort to combine WINE with the QEMU x86 emulator which is an emulator because it emulates CPU calls. Hint that it's an emulator is in the name "QEMU" and an actual quote from the wiki page you linked and clearly didn't care to read: "Running Windows/x86 Applications: See Emulation"
EDIT: Let me also quote from the readme file of the Hangover project:
No, the point of Rosetta was to be a stop-gap for 3rd party software because Apple did all porting in-house software long ago.
Prism is Microsoft's tool for staying lazy. Microsoft ships ARM-based Surface tablets since 12 years!!!!!
In all architecture transitions (PPC->Intel then Intel->ARM), Apple Chess has always been a native port from day one.
I firmly maintain that if Microsoft gave a shit about ARM, they would be defaulting every one of their compilers to produce fat x86/aarch64 binaries. The reality is, however, that they don't care about the hardware so long as it is good enough.
Wasn't the point of .NET once that native binary code isn't needed? I'd say if Microsoft gave a shit about ARM, everything would have been ported to .NET.
The 68k to PPC transition was rough though. It wasn't until system 8 that Mac OS on a PPC mac was fully PPC code. But that was also a much different Apple that's nothing like the Apple of today.
this is for the transition. no point in porting your software if nobody has the hardware. This will get people to get the hardware, as they can just keep using the existing software, and wait until it's properly ported
Edit: you people really think windows is the only software that needs a translation? Do you only ever use your OS on your computer, and not a single software more?
Nobody will buy the hardware if they can't commit to supporting the software. In a previous role, I was responsible for advising purchasing decisions for my company's laptop fleet. The Surface X (Arm edition) looked cool, but we weren't willing to take the risk, because at the time Microsoft had far worse transitional support than they do now. It's gotten better, but no one in their right mind is going to make the kind of volume purchases that actually drive adoption until they demonstrate they are in it for the long haul. It's a chicken and egg problem, and Microsoft doesn't care what hardware you are using, so long as it is running Windows or using (expensive) Windows services.
What better way to sell devices than by halfassing them to oblivion?
Apple released a native x86 version of Tiger with their first Intel Macs.
Sure, but the vast majority of Mac software at the time, including loads of first applications from Apple, couldn't run on Tiger. You had to run it in the "Classic" environment - and they never ported that to Intel.
Tiger shipped just 4 years after the MacOS 9.2 and plenty of people hadn't switched to MacOS X yet.
The reality is Apple only brings things forward when they can do it easily.
Apple has done eight major CPU transitions in the last 40 years (mix of architecture and bit length changes) and a single team worked on every single transition. Also, Apple co-founded the ARM processor before they did the first transition. It's safe to assume the team that did all those transitions was also well aware of and involved in ARM for as long as the architecture has existed.
No, this won't get people to get hardware that looks horribly slow because everything needs to run through a translation layer. They do have the sources. They could just recompile them for the new hardware. If their sources are not total crap.
I'd expect there's quite a lot of assembly and endianness-dependent stuff here and there. It's Microsoft. Their culture is about pride of things being arcane-complex inside, cause if you can untangle that, you are a good programmer. They think that. I think they think that. Maybe they are just vile.
You may be spot on with that. Though the assembly part can be fixed by code translation at compile time. Endianess and shitty programming habits are another thing that the cross-executor must deal with, too, so maybe this has been covered already. Or it will blow up in their faces, anyway.
Both arches are little endian btw.
I'm sure they have found something to make the port problematic.
I mean, it's a Microsoft product.
Windows NT historically ran on lots of CPU architectures, PowerPC, MIPS, Alpha, Itanium, etc, and that included the bundled software like 3D Pinball. I would have expected it to still be quite portable.
20 years have passed.
Microsoft really never do that port if they have a translation layer