It's Arm based, although they barely mention that.

Yes the lack of transparency on ARM architecture and the obfuscation of the RAM capacity with just the slot information is annoying. Not sure if it is deliberate to sell this at a premium to "mainframe" customers or whether its just their marketing folk not being on the ball. Fascinated by the fact Japan has a 2nm process node but I suspect that too is marketing. Perhaps the 2nm portion of the chip is done at TSMC and the rest of the package done in Japan or something like that. It's not like there's a plethora of 2nm Fabs around the planet to choose from.

It looks to me like it is an AI optimized HPC CPU and while HPC CPUs are actually quite fast, they are not particularly well suited for transformer based neural networks.

It's weird that they don't give out any of the interesting numbers like number of memory channels, how much SRAM they have (CPUs tend to have more of it) or what their expected performance is going to be.

If they didn't mention SVE2, I wouldn't have known either... that would make it arm9 at the earliest...

Quick Google result is it’s basically a Neoverse V2 system, so yeah, armv9.

Edit: it’s funny because this article from 2021 mentioned Fujisu precisely https://siliconangle.com/2021/03/30/arm-unveils-armv9-archit...

No it is not at all Neoverse V2, which is obsolete and has much lower performance.

It is a custom Armv9.3-A design (same ISA like the Arm C1 CPUs from the flagship smartphones of 2026), but it has double-width execution units for SVE2 (i.e. 256-bit width, vs. 128-bit for the other Arm CPUs) and it has some ISA extensions for AI/ML, e.g. instructions for inference with FP8 (BF16 is already supported by the standard Arm ISA).

Despite the fact that Armv9.3-A may include SME (scalable matrix extension, like in the Apple CPUs and in the Arm C1 CPUs), Fujitsu did not mention SME, so I assume that they did not implement it and they rely on their enhanced SVE2 (which is not surprising, while the origin of Arm SME is at Apple, the origin of Arm SVE is at Fujitsu).

They actually do not in that article. I had to look elsewhere to find that out. Weird, one would expect that a big announcement like this would probably need to be vetted against licensing agreements with Arm that would probably want that fact to be prominently highlighted in press releases.

It is in the article - they cite "SVE2" support

Interesting to note that Fujitsu did this when the SPARC architecture was popular: they enhanced/developed a CPU for the same ABI.

Seems they have decided they don’t want to create their own architecture, but take the popular architecture and build on it.

Thanks kinda how Japan works. Inventing something new is hard, but taking something that's a cool idea and making it actually usable is well within their wheelhouse.

See: - Blue LEDs - Quartz Watches - Lithium-ion Batteries - Bidets

I'm sure there's plenty of other stuff invented in Japan, but that's really beside the point.

The industry is now mature enough that nobody really wants the headache of a new architecture at this point in time, Risc-V got a pass for being a grassroots movement growing out off FPGA's since the IP situation was more or less clear or even predatory with all existing architectures, Power, Sparc,SuperH,68k,etc are buried for good reasons.

I had this idea that Fujitsu was one of those Japanese conglomerates that had operations in all kinds of markets, from electronics to heavy earth moving equipment to air conditioners to locomotives. But that doesn't appear to be the case so I'm wondering which company I'm confusing them with.

Edit I think I was thinking of Mitsubishi.

Sun invented SPARC, Fujitsu just happened to be the last producer since they built mainframes on it. Reading it seems like they plan to stop producing Sparc processors and machines in a near timeframe so that makes this announcement less surprising.

For many years the Fujitsu SPARC implementations were much faster than the Sun SPARC implementations.

During the decade 1995-2005, until the 64-bit AMD Opteron servers with Linux offered an alternative that crushed any kind of SPARC CPU with Solaris by a much higher performance combined with a much lower price, the SPARC Sun or Fujitsu servers dominated the market for servers used to host the CAD/EDA design tools used in electronics engineering, for the design of integrated circuits or electronic equipment. This means that all the EDA software from vendors like Mentor, Cadence, Synopsis etc. was available only for Solaris. That kind of software could not be run on Windows, due to the 32-bit memory limit. During that time, whoever got Fujitsu servers instead of the sluggish Sun servers, was very lucky.

Not mentioning the architecture is rather strange. Being Fujitsu I'd expect SPARC, but apparently not. Maybe we're reaching a point where some circles either don't care or just defaults to ARM?

Obviously they can just ignore the license in the future and continue development out of a local branch, but it's also a bit disingenuous to speak of "sovereign infrastructure" and then use licensed processor design.

Thanks. Looked for that in the article and couldn't find it.

What are the GPU capabilities?

Iam very curious as to how well it'll perform outside of Asia.

Fun fact, Fujitsu used to run their own fabs in Japan until they were sold to UMC and now they're another UMC fab although they are stuck at like the 20nm node. So this is likely made at JASM.

I think they'd say if the CPU was fabbed in Japan, instead there's some very "careful" wording:

next-generation CPU, FUJITSU-MONAKA [1], designed and developed in Japan

Fujitsu MONAKA Server, powered by the FUJITSU-MONAKA CPU, enhances sovereign capabilities through domestic manufacturing,

Right below the headline it says:

Achieving world-class AI inference performance through Japan-developed 2nm 3D-stacked CPU and server integrated, developed, and manufactured in Japan

Sounds pretty clear to me

So, server manufactured/integrated in Japan; actual chip manufactured elsewhere (but "developed" in Japan, whatever that means)?

Doesn't really make sense to me. The whole "sovereign" thing is to basically say you won't be screwed if you go to war with a country tomorrow because you are dependent on their supply chain. Nothing about this changes that IMO. They're still getting the chips fabbed somewhere else and run the same risks.

Indeed, it is extremely clear: by not saying "manufactured in Japan", the words "developed in Japan" tell you that they drew up the designs for the CPU in Japan, and then sent those designs off to a fab outside Japan for actual manufacturing. Then they bring those CPUs back to Japan, so that the server can be manufactured in Japan even if the server components are not.

That manufacturing step may change in the future, but right now that CPU is not "Made in Japan", it's only "Designed in Japan".

They did a presentation at Hot Chips, with all these details.

The core die is made with TSMC-N2P, while the SRAM die and the peripheral die are made with TSMC-N5.

Their CPU is designed in Japan, like the AMD CPUs or the Intel CPUs are designed in USA (the latest Panther Lake Intel CPUs have returned for fabrication to USA in 2026, but they also cost double than the corresponding Arrow Lake models made at TSMC in 2025, and their GPUs are still made at TSMC).

The compute part must have been made in Taiwan because it uses TSMC N2. TSMC N2 is only available in Taiwan right now due to a law restricting the latest node to Taiwan for 1-2 years.

It's 2nm, so it has to be manufactured by TSMC.

Where are the CPUs fabbed? They make a big deal about "sovereign" but is the CPU actually made in Japan, or do they rely on TSMC?

Also odd how big an emphasis they put on AI inference when they don't build the GPU?

The article says that it’s manufactured in Japan.

where exactly does it say that? I don't consider "designed and developed in Japan" to be the same as manufactured there

At the very top of the article: "Achieving world-class AI inference performance through Japan-developed 2nm 3D-stacked CPU and server integrated, developed, and manufactured in Japan"

"Japan-developed CPU..." plus the server itself (parts, power supplies, case, etc.) integrated, developed and manufactured in Japan. It sounds like they're weasel-wording it a bit, but I don't think the CPU itself is manufactured in Japan, only "developed."

The two made-in-Japan, premium grade, Fujitsu laptops I had to work with were by far the worse pieces of electronic I have ever used. Both exhibited identical defects: fans running continuously at maximum speed, and the batteries would completely die within hours of the devices being powered off. Windows or Linux. And don't talk about that tiny unresponsive trackpad to me. Never again.

The Fujitsu Lifebooks were legendary for their robustness back in the day, I'm genuinely sad you had that experience.

The only fujitsu laptops I used was back in 2011- it was a budget version for on-call and it was fine..

Sounds like the fans running 100% probably contributed significantly to the issue here. If I had to guess it was likely that the C-States were disabled in BIOS somehow so the CPU clock was running at full tilt the whole time, maybe combined with a bad thermal paste job.

I'm not here to defend Fujitsu but I've had really bad experiences with basically every major laptop brand (Dell: majorly bad coil whine and especially faulty soldered RAM, HP: keys vanishing from the keyboard and very weak hinges that break all the time, Apple: The GPU unsoldering itself and the butterfly keyboard shenanigans).

I don't really know any brand with a flawless track record sadly.

Before anyone brings up Thinkpads, they're trading on a reputation that hasn't been true for over a decade. If you have fond memories of a thinkpad it's most likely that you had it from before 2016, or it's "fine", but certainly not great.

Their consumer electronics arm is completely unrelated and also majority owned by Lenovo

What year? The ones I had were the best. Very expensive, but service at the office & at home, very sturdy, very long battery life. That was somewhere early 2000s.

https://en.wikipedia.org/wiki/British_Post_Office_scandal

Their software is so poor that it caused probably the biggest miscarriage of justice in history. Well that and Fujitsu staff colluding with post office executives to put innocent people in prison rather than admit there was a problem

The 'Fujitsu' that made the shitty software was a British consulting company that was acquired by Fujitsu [1] to farm public contracts. This is made by the Japanese parent company.

[1] https://en.wikipedia.org/wiki/International_Computers_Limite...

Not trying to be obnoxious, but it's still Fujitsu.

One problem we’re going to have with AI hardware is coming up with a standard set of specifications that are comparable. I don’t really care about the CPU GHz and the memory bandwidth, at least not directly. What I really want to know is how many tokens per second this will deliver, but that also depends on the model. We need a standard metric for that. Perhaps we agree on a specific open weight model (e.g. GLM 5.3 Flash or Qwen vWhatever) and then measure TPS on the hardware of interest.

I always heard of GB/s as most important number ... AI told me their 8800 MT/s on 8 Byte, 12 DDR5-Channels means 845 GB/s. A Nvidia RTX 4090 has 1008 GB/s. Nvidia B200 has 8000 GB/s. Is this the right way of looking at it?

You have to load the model weights into VRAM over PCI-E (from RAM). So the (PCI-E) bandwidth strongly affects time to first token.

You have to run inference on the GPU by reading and writing to VRAM. So TFLOPS of the compute matters, and bandwidth to the VRAM (Always integrated with the GPU, rarely a bottleneck), and this strongly affects tokens/s

If you're doing training workloads or offloading to system RAM, it gets more complicated. (And mostly bound up trying to feed compute on time)

(Edits for clarity.)

Wow a corporate TLD in a wild, never seen this outside of the erstwhile domains.google

I fail to see how they will take a significant market share or even break even on this venture.

It's an overcrowded market. Far better would be to focus on semiconductor supply chain, which Japan already supplies some elements, to sell to fabs.

Because the bottleneck is the fabs. If a new 2 nm fab came online today, it would immediately sell all its capacity to 2030 no problem, without Fujitsu trying this gambit.

It's not 'sovereign', the architecture is not designed in Japan, the silicon is not fabbed in Japan. This whole thing is sideways.

It's a custom Fujitsu micro-architecture.

It's ARM with extensions.

the architecture is not designed in Japan

The text says "next-generation CPU, FUJITSU-MONAKA, designed and developed in Japan".

Every developed country is going to push for their own homemade chips. Japan used to make Sparc CPU's back in the day. Probably many others I'm not aware of.

Every developed country except Australia, perhaps. This government is atrocious. The record for highest number of bureaucrats per capita in the world is owned by Australia. All they know how to do is tax people. All the wealthy people have left, or are leaving.

The record for highest number of bureaucrats per capita in the world is owned by Australia

You have been convinced by fake news, please recheck this claim, its false.

wealthy people

*rich people

All they know how to do is tax people

Oh god you're one of those. People who complain about taxes have historically been on the wrong side of arguments.

I've been calling for high-multicore CPUs (at least 100 cores) with local memories for a quarter century now. No winners so far.

A Pentium 4 hit 3.8 GHz longer than that ago in 2004, so that's not special. And the estimated price will be $7,000-10,000, which isn't special either since that's about 10x more than it should be.

Hot take: GPUs disrupted the CPU industry to such a degree that CPUs never recovered, and like the k-shaped economy, the current status quo only serves a small fraction of customers. We can and should do better, but sadly we won't. Still, it's good that Fujitsu did this, for the competition if nothing else.

Unless they are used for multi-processing in classical UNIX fashion, or proper microkernels, most applications will hardly take advantage of them.

Managed languages runtimes are probably the ones that would be better equipped to take advantage of them, for distributed JIT, GC and asynchronous code.

The Connection Machine style with StarLisp.

Very few devs can write optimal multi-threaded code that explores the single digit count of cores on their laptops or phones already.

IMO we are still far from discovering a truly usable concurrency paradigm (if one even exists).

Maybe if designing software like digital circuits, which are more parallel in execution.

However one could argue that FPGAs are already that, and still we come back to a skill issue.

I am also not an expert, cannot make heads or tails about SIMD algorithms, and in what GPUs goes, only traditional shading languages.

Let alone algorithms that on top of that, should take optimal advantage of all available CPUs.

Ya functional programming is key, as it's equivalent to a spreadsheet or digital circuit. In other words, it removes the element of time and often dynamic state, which imperative programming generally fails to do.

IMHO most concurrency problems don't actually need async behavior, they need higher-order methods and models which behave deterministically by encapsulating async behavior internally.

Another maturing solution is to use SAT solvers to prove that all exceptional behavior and failure modes are handled. I'm hopeful that AI will help with that and allow us to exercise programs fully, rather than rely on unit tests and fuzzing.

Personally I think that the UNIX model of orchestrating small async programs that do one thing well is the only proven mainstream solution. Erlang and Go come really close, but unfortunately we need a hybrid of the two, which doesn't currently exist. The pattern for that is functional core, imperative shell. Which mimics the real world where business logic can be formerly proven correct or constrained by types and categories, then we wire up programs cookie cutter style. That avoids the use of monads (promises/futures in imperative languages), which are the main footguns. The closest language that does that is ClojureScript, whose runtime is analogous to suspending and resuming a coroutine or green thread that makes Lisp calls (although that's a poor fit and I'm sure I'm wrong about it).

But you're right that we don't currently have a language that can recruit multicore CPUs. I used MATLAB/GNU Octave in the past, but think that Julia probably has a brighter future since it can already run on GPU mostly unmodified. I would not try to do it with a mainstream language like C# or Python, or even PHP for that matter. Although some of PHP's multiprocessing metaphors are pretty solid, since they intentionally use processes instead of threads like in Ruby. There the problem is latency introduced by poor process models used by Microsoft and Apple, not something fundamental with spawning processes. Real-time Linux attempts to unify the kernel under one process model to provide deterministic timing, which is hard enough for regular Linux and probably out of reach of the big OS companies, because money can't buy everything.

Back in 2008 Fujitsu has one of the best performing 10Gbps Switches. We were building 40 Gbps packet sniffers at Google (4x 10 Gbps NICs) and needed switches that could do things like mirror traffic across ports at line rate. Fujitsu was way ahead of the pack. I always wondered what held them back from building a meaningful networking business in the US.

I always wondered what held them back from building a meaningful networking business in the US.

It was just timing. Their networking gear was built on some very impressive ASICs which became commodity chips a few years later before they could grow. Arista, Juniper, et al ate their lunch using other vendors’ IP. IIRC it was Broadcom and Fulcrum that released the chips that killed them.

Having a us based vendor. Fujitsu is huge in Asia for ISPs and so is Mitsubishi and Sumitomo (yes they made or used to make network equipment too)

We were building 40 Gbps packet sniffers at Google (4x 10 Gbps NICs) and needed switches that could do things like mirror traffic across ports at line rate

I'm sure there were good reaasons for this, but man this just sounds bad. Like that's the spec I think NSA must give to their contractors outfitting 611 Folsom Street's Room 641A

There are companies that mirror their traffic to storage for a few days to be able to look back and troubleshoot issues. ALL their traffic, proactively.

Nah, packet mirroring is a standard networking feature and ideally every feature is line rate.

It does sound bad the way OP described it, but packet or HTTP mirroring is a standard feature of A/B testing and blue-green deployments of a very critical code. Mirror traffic between version 1 and 2, then compare response body, response time and return response A to the end users.

But the comment says ”we were building packet sniffers” … and needed mirroring as part of that.

Will it lock up thousands of innocent self-employed post office contractors as part of its instruction set?

https://en.wikipedia.org/wiki/British_Post_Office_scandal

Probably not, Japanese firms excel at hardware and generally build extremely poor software. This a hardware product, so consequently it is probably fairly good.

What caused this?

Honestly, no idea. In my career I have worked with a lot of Japanese firms and have always found their engineers to be excellent. I used to think it was a lack of consideration for UX, but that obviously can't be true when you see excellent examples of UX in hardware (e.g. Switch controls), even though its exceedingly rare on the software side.

If anyone on HN knows (there are several other commenters more deeply steeped in Japanese engineering culture), I would love to know why as well.

I think Ruby would be a counterpoint - although it's the only one I know of.

I worked for a Japanese company although in a local office with local management. Through all those layers of protection I got the impression that they suffer from what all corporates suffer from - no software engineers that have made it to the top. Software companies run by people who have no clue.

In the US, for example, I think some people who have a clue or a partial clue have made it up the ladder in some places and therefore although everyone there has their horror stories of idiotic behavior it is probably somewhat better.

If anyone is curious and want to skip all the PR talk:

Combined with SVE2 vector operations and software optimization,

It’s ARMv9.

I wonder how many cores they plan to cram in there, at least like 256 right?

I hoped it would be SPARC.

I hoped it would be Alpha.

Why did they bury the lede so much on what the ISA is?

More detailed presentations about the Monaka CPU:

wccftech summary: https://wccftech.com/fujitsus-monaka-chip-3d-stacks-2nm-cpu-...

2026: https://global.fujitsu/-/media/Project/Fujitsu/Fujitsu-HQ/te...

2023: https://global.fujitsu/-/media/Project/Fujitsu/Fujitsu-HQ/te...

FugakuNEXT, the supercomputer it will be used in, also some details about the next-gen Monaka-X: https://global.fujitsu/-/media/Project/Fujitsu/Fujitsu-HQ/te...

For a single CPU: 844 GB/s memory bandwidth (12 channels of DDR5 RDIMM, 8800MT/s). 4.3-6 TFLOPS.

Basically comparable to a modern (although not top-end) GPU, so good for HPC & AI workloads. (though only 2 CPUs per node, with GPUs 4-8 is more common)

The US administration created at least 90% of what we now call technology sovereignty concerns. Technology sovereignty is front and center in this announcement. Before the president started making wildly inappropriate remarks about grabbing territory from allies and other previously unthinkable utterances, almost everyone was happy to buy technology from US hardware and software vendors. Complacency about the state of democracy and rule of law in the US was the norm.

Why does this matter? Markets outside the US account for about half of many US technology vendors' revenue. Who is going to speak up first?

there are many things to blame POTUS for. This isn't one of them... most major fabs were already outside the US to begin with and the US chipmaking industry (well, really Intel) was really struggling even years ago.

I don't see the connection. No matter where US chips are manufactured, it's not the location of the fab that causes technology sovereignty concerns. Those concerns come from questions about the stability and rationality of our leadership: can my jet fighter get nerfed if I wanted to defend Greenland from an invasion? Are my spies being spied on by US technology?

Those questions didn't used to be significant factors.

I'd argue that the consolidation of the chip industry in Taiwan has had the most impact here. If/When China does move to take over Taiwan the global chip supply will be devastated and countries are well in their right to want to diversify from that. If anything, POTUS statements just also solidified the point that like Taiwan, they should not rely on USA or any other country for that matter. Hence why so many countries are pushing for some level of self sustainment.

Named after monaka, a traditional Japanese confection of sweet red bean paste sandwiched between two wafers.

https://en.wikipedia.org/wiki/Monaka

It's not terribly popular even in Japan, since it's dry, bland, fragile and has to be assembled on the spot or it goes soggy.