IIRC, they had different licensing prices for cores that would run z&#x2F;OS workloads and cores that would run Linux on s390x (and other tier for Java, I think). This looks like they’ll have one for Linux on ARM as well.

I thought about that, too. I think they’re doing this for the same reason IBM has supported Linux LPARs: 
since a lot of customers who lease System&#x2F;z currently probably get overprovisioned hardware that they’ll never fully use, why not try a last-ditch attempt to sell the excess capacity as ARM LPARs?Now you’re thinking like a Big Blue sales rep.

Not even the weirdest thing IBM did to get compatibility between their mainframes and other CPU architectures. To build the XT&#x2F;370 and AT&#x2F;370 expansion cards, they custom-ordered modified 68000s that decoded System&#x2F;370 instructions instead of the 68k instruction set, with most of the instructions handled by the new microcode and the few stragglers software-emulated:<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;w&#x2F;index.php?title=PC-based_IBM_mainframe-compatible_systems#Personal_Computer_XT&#x2F;370" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;w&#x2F;index.php?title=PC-based_IBM_main...</a>

ARM can emulate z workloads. <a href="https:&#x2F;&#x2F;hercules-390.github.io&#x2F;html&#x2F;index.html" rel="nofollow">https:&#x2F;&#x2F;hercules-390.github.io&#x2F;html&#x2F;index.html</a>(or QEMU, for partition level emulation).

This feels like a baby step towards Arm being able to emulate z&#x2F;Arch workloads, maybe with a bit of secret sauce for certain specific operations, which doesn&#x27;t seem very much like IBM.

Does anyone else make an ARM CPU that is expressly designed for performance with good cooling ?

At least back in the day, there was talk about Nvidia + ppc64le. Wasn&#x27;t there even a supercomputer with that setup? But I guess that has fallen by the wayside.

ARM has better software support for AI applications and half of their presentation was about their inference accelerators that can go in the mainframes (and POWER machines).IBM mainframes are almost designed by their users. The previous generation skipped a lot of speed boost on the CPU side because their users didn’t want the machine to blow over their power delivery limits.Now, with their architecture behind it, I’m sure these ARM Linux partitions will have the fastest ARM cores ever made. My experience with Linux on s390x is that it feels like a normal server that’s just ludicrously fast - almost as if it came from the future.

I wonder how they handle potential differences in memory barriers, instruction order scheduling and other stuff and do they run the core in one mode continuously or do the mix instruction streams from different instruction sets? Anybody got a link to an article?

No, this is more like any modern processor, which translates instruction codes into micro-ops. To over-simplify IBM just has two of these units per thread rather than one.

.... I -so- miss RealWorldTech write-ups, I&#x27;d love to see what David Kanter would have to say about this thing...

&quot;code translation in hardware&quot; microcode is called &quot;native&quot;

They were pretty clear at Hot Chips that it&#x27;s native

Transmeta did code translation with a software JIT. The hardware side had specific support for x86 semantics, similar to how Apple&#x27;s M-series has supporting hardware for Rosetta&#x27;s AOT translation, but neither executes x86 machine code directly.

Is this like the Transmeta processors doing code translation in hardware?

If by that you are asking whether it has a dynamic ISA controllable at runtime, it appears not. This looks to be a Z processor with arm instructions implemented.

I was curious, is it conceptually similar to Data General Fountainhead project?

Mostly because big endian is the past.

It&#x27;s a little more complex than that, IMO.For starters, IBM did also do the CPU for the GameCube, and that was likely a part of the Wii using an upgraded PPC arch for that.On the flipside, there is the theory (I think even Copetti brings it up in their XBox 360 Architecture breakdown [0]) that IBM using the Cell PPE for the 360&#x27;s tri-cores left a sour taste in Toshiba, but more-so Sony&#x27;s mouths.I think the big &#x27;X factor&#x27; though, was that, for as much pain as it caused AMD in the short term, (it&#x27;s so easy to forget their &#x27;malaise&#x27; era, i.e. Early Bulldozer and the GloFo split pains to their margins[1]), AMD made all the &#x27;right&#x27; choices to let the console vendors have their cake and eat it too.Namely, AMD was more than happy to do a custom core if there was a volume contract (similar to what IBM was willing to for the 360&#x2F;GC&#x2F;Wii) but also now had a capable, in-house GPU. (And thankfully had Bobcat as a stepping point towards Jaguar[2])There&#x27;s part of me that asks, if AMD had an ARM core, if we would have all Consoles powered by AMD chips now. Nintendo likely bought into Tegra because it was an ARM core, and for better or worse their mobile stuff by the time of making that choice had 15+ years of proven ARM success (GBA, DS, 3DS) behind it.(See also, Intel in the 2010s scrambling with half-assed promises of integrating custom functionality or FPGAs with x86 cores.)[0] - <a href="https:&#x2F;&#x2F;www.copetti.org&#x2F;writings&#x2F;consoles&#x2F;xbox-360&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.copetti.org&#x2F;writings&#x2F;consoles&#x2F;xbox-360&#x2F;</a>[1] - From what I recollect, the GloFo split and how the contracts were drawn up as far as their production, had a huge impact on their ability to produce due to yields and thermals, as well as the contracts for how GloFo got paid; it was at least part of them diversifying with TSMC as soon as they reasonably could.[2] - As a Rant, I am pretty sure, if Jaguar had Desktop&#x2F;Mobile versions that included a Dual channel DDR controller, they would have cleaned up on the low cost laptop market. I had one with, I think it was an A5000 or A5200, and for how tiny the battery was it could last wayyyy longer than any of the intel laptops I had for the time, but churned if you were doing memory heavy stuff.

Having a presence in the consumer market is not a requirement for being innovative.IBM stopped building servers based on x86 because the margins were too thin for their tastes, but they never stopped building on top of POWER and Z.

Xbox 360 used an Intel CPU.PS3 used the Cell processor but it’s debatable how much that was an asset vs handicap. Total PlayStation sales dropped for that generation vs both PS2 and PS4. The manufacturing costs didn’t fall nearly as fast as expected and it was a poor fit in terms of cross platform development etc.PS4 moved to AMD.

More like mid-2000s, even with the least charitable interpretation.There was a time when IBM dominated console CPUs for a massively successful generation (PS3, Xbox 360, Nintendo Wii).

But those ARM and s390x decoders have a “Telum III” architecture behind them with a cache that’s pretty innovative.IBM has never stopped innovating. It’s just that most people can’t afford their machines.

To be fair, IBM did this in the 90s with the PowerPC 615, which had PowerPC and x86 decoders on the same core.

At this point no one is buying into mainframes are they?So they are just selling to the existing pool of users for which the price just has to come in under the cost&#x2F;risk of rewriting all their ancient stuff.

A single mainframe can handle workloads that would take dozens of x86 cloud servers, with nine nines of uptime. If you can afford it it pays for itself in terms of reliability and scalability.

The z mainframe team does good technical work but then the high price cancels out all the value of that work. I&#x27;m not sure if that counts as innovation or not.

RP2350 has separate cores for that. This is one core that speaks both.

There are already microcontrollers that have both arm + riscv support. This isn&#x27;t something insane.

Yeah, a huge chunk of IBM&#x27;s service revenue has always been effectively mainframe services, with wall street accounting spin.I suspect that almost zero companies adopted mainframes after 1980 or so, so it&#x27;s ALL legacy market. However, IBM always invests a lot of money in hardware to keep the mainframe perceptually leading edge and &quot;sexy&quot;, so they can hold-on to those customers. So you gotta give them credit for that.(IBM and Microsoft were always &#x27;in the same breath&#x27; for years, Microsoft totally out-smarted them, and IBM gave up on that.)

I was one of them, but I don&#x27;t think IBM hasn&#x27;t innovated, my contention is more that they have de-emphasised software and hardware in favour of services, and they&#x27;ve moved away from consumer-facing activity to be entirely B2B, and that there is an overall feeling of slow decline.Their hardware advances are real, Power chips are still excellent and IBM&#x27;s mainframes are pretty unique, but the niche for both of those seems less relevant over time and some of this stuff looks to me like hype-work to keep the name relevant while the leadership place ever more emphasis on enterprise services and consultancy.Maybe I&#x27;m wrong, but they aren&#x27;t a company that get mentioned in the same breath as Microsoft, Google, Nvidia or Apple, not any more.

What does IBM actually do? I just can never understand their business and operating model. It seems like they just do a bunch of random stuff and sell to the most enterprisey of enterprises.

Their research is usually behind paywalls. I miss the days when they published their journals and made PDFs available for download.

well that&#x27;s nonsense. IBM does incredibly cool stuff.<a href="https:&#x2F;&#x2F;research.ibm.com&#x2F;blog" rel="nofollow">https:&#x2F;&#x2F;research.ibm.com&#x2F;blog</a>

Those takes are wrong with or without this particular processor.

I was reading HN comments yesterday shitting on modern IBM for being a non tech consulting company that has not innovated since the mid nineties.

Oh is that why the page is like 50 megs.

Right click -&gt; Open image in new tab -&gt; zoom inIf you haven&#x27;t already.

IBM Unveils Next Generation Dual-Architecture Processor for IBM Z and LinuxONE