Linux Prepares For Next-Gen AMD CPUs With Up To 12 CCDs

[coder]

So if you were looking to buy a new Chromebook it would be a good idea to wait for the product refresh in the new year and get something with at least 1 P core then? If I'm reading between the lines here right. I was thinking about pulling the trigger on a Jasper Lake 4 core Pentium Silver model this year but now I'm thinking about waiting.

Depends on how urgently you need it. Given that I found no leaks of a Jasper Lake successor, my guess is that it'll be a ways off. You could be looking at the better part of a year, before it's in machines that are available to order.

Still, if I didn't really need an upgrade, I'd probably hold off for Gracemont or the next thing from Mediatek. Don't assume you'll get a P-core by sticking with x86, but you would get a decent IPC & frequency boost + AVX2 (256-bit). Currently, Tremont and before have just SSE-family (128-bit) instructions.

Edit: also, the GPU should be upgraded to Xe. Jasper Lake seems to use Gen 11 (Xe is Gen 12).

[jaxa]

So if you were looking to buy a new Chromebook it would be a good idea to wait for the product refresh in the new year and get something with at least 1 P core then? If I'm reading between the lines here right. I was thinking about pulling the trigger on a Jasper Lake 4 core Pentium Silver model this year but now I'm thinking about waiting.

I don't know for sure that Intel will phase out E-core-only processors with Gracemont. But there will be Alder Lake Chromebooks coming next year:

https://www.digitaltrends.com/comput...books-laptops/
https://chromeunboxed.com/hp-chromeb...tel-alder-lake

The possible configurations are 6+8, 4+8 (big die), or 2+8, 2+4 and 1+4 (small die).

This roadmap shows Jasper Lake at the bottom, stretching into Q1 2022:

https://www.notebookcheck.net/Intel-....568734.0.html

That could be a sign that there is nothing after Jasper Lake, or that it will just take longer for a Gracemont-only successor to appear. It also probably means that Alder Lake 1+4 will be more expensive. Beyond being brand new, it will also be made on the newer "Intel 7" node.

Another consideration is that graphics performance should be vastly improved between Jasper Lake and Alder Lake-M. Jasper Lake maxes out at 32 Gen11 execution units, while Alder Lake-M starts at 48 Gen12.2 execution units and has 64/80/96 options.

I don't want to dissuade you from buying anything if you need it soon, so take it all with a grain of salt.

[jaxa]

I didn't find this figure, when I looked for it. However, the die size comparisons would suggest otherwise, given that Alder Lake's die also contains GPU.

We shouldn't assume that. With a couple exceptions, ARM never went down that path. And Intel quickly walked back from the SMT-4 they put in the original Atom.

My source for the die area analysis and hyperthreading claims is Moore's Law is Dead, a YouTuber who leaked the Zen 4c details recently. I don't think anybody should expect hyperthreading on E-cores soon, but it seems like a good way to counter AMD's future dense/small versions of their big cores which will have hyperthreading IIRC.

SMT-4 was only in the Xeon Phi products, I think. I'm suggesting SMT-2 only.

OMG, maths! 128/96 = 4/3 -> 33.3% increase.

Yeah, don't know what I was thinking there. My point is that Bergamo Zen 4c cores will not be large when compared to Intel E-cores.

I'm wondering how long this core-count race will continue. Are you aware that Epyc already has a way to segment the CPU into up to 4 NUMA domains? It's called the NPS setting. And the reason they do it is because SMP scaling starts to break down, when you reach that many cores.

Epyc "Turin" (Zen 5) is already rumored to have up to 256 cores. Some customers, like the "hyperscalers", will take everything they can get. The humble 32-core and 64-core (and someday 96-core Zen 4 Threadripper) workstation users have to question if they will ever need that many.

Intel has put E-cores in their Atom-branded embedded server CPUs for about a decade, now. The current Snow Ridge line has up to 24x Tremont cores

BTW, Wikipedia lists a "Grand Ridge" with no other details yet for Gracemont.

With E-cores as strong as Gracemont? Of course they will! Jasper Lake hasn't even been out for 1 year, and the "Intel 7" production line is probably backlogged on just Alder Lake and Sapphire Rapids. However, once some capacity starts to open up, there's no doubt they'll refresh their entry-level SoCs.

The Ultra Mobile they announced has a 96-EU iGPU. It's clearly a premium solution, not entry-level. Even Lakefield (pairing 1 P-core + 4 E-cores) was reserved for the highest product tier of MS Surface.

I have to concede that you will be charged more for Alder Lake-M 1+4 initially. But Lakefield was an aberration of a product that used 3D stacking and was too expensive. Alder Lake "M5" 1+4 is apparently targeting a similar TDP, without the tricks that Lakefield used AFAIK.

It just seems to me that 1+4 makes more sense than ever putting out another 4-core Atom, especially if it can target the same 6 Watt TDP. And it could use the "bad" 2+8/96EU dies.

[kylew77]

Thanks Coder and Jaxa. You were most helpful. More helpful than Reddit was to me.

[bridgman]

I didn't find this figure, when I looked for it. However, the die size comparisons would suggest otherwise, given that Alder Lake's die also contains GPU.

Do you have a good source for this?

I was curious about this as well so when the first die shots were published I spent a bit of time with die size info (for scaling) and a tape measure.

If you omit L3 I think the numbers were something like 8 mm2 for Golden Cove, 4 mm2 for Zen3 and a bit over 2.5 mm2 for Gracemont. I included a ring agent in the AL numbers (1/4 of a ring agent for Gracemont) since the corresponding functionality in Zen3 also seemed to be included.

Die shot was for the large die with 8 GC and 8 Gracemont... GPU and display were about 30% of the die.

This is going from memory though... I had the numbers written on a piece of junk mail but cleaned up the office last weekend... might have to measure it again this weekend just to be sure.

[coder]

Thanks Coder and Jaxa. You were most helpful. More helpful than Reddit was to me.

Another thought would be to hunt for a deal on a 4-core Tiger Lake laptop. Tiger Lake is fully decent, better than any Gracemont-based CPU, and has a Xe iGPU. After the holidays pass and Alder Lake laptops hit the market, maybe there could be some deals on some Tiger Lakes?

Same general idea applies to AMD-based laptops, BTW.

[coder]

I don't know for sure that Intel will phase out E-core-only processors with Gracemont. But there will be Alder Lake Chromebooks coming next year:

https://www.digitaltrends.com/comput...books-laptops/
https://chromeunboxed.com/hp-chromeb...tel-alder-lake

The possible configurations are 6+8, 4+8 (big die), or 2+8, 2+4 and 1+4 (small die).

Wow. 28 W and 45 W Chromebooks? That sounds like quite a lot of horsepower for a Chromebook. They won't be cheap.

This roadmap shows Jasper Lake at the bottom, stretching into Q1 2022:

Yup. That's what I'm talking about. I think the "Intel 7" production lines are going to be under some stress for quite a while, with Sapphire Rapids ramping up. As these entry-level CPUs are some of Intel's lowest-margin products, they'll be at the back of the queue.

That could be a sign that there is nothing after Jasper Lake, or that it will just take longer for a Gracemont-only successor to appear.

Given that JSL launched in Q1, 2021, you can't read anything into the fact that it's not superseded by the end of Q1, 2022!

[coder]

SMT-4 was only in the Xeon Phi products, I think. I'm suggesting SMT-2 only.

Yes, it was, but that was sufficiently niche that I figured it wasn't worth a footnote. Besides, can you still call it an E-core, when it's also got dual- AXV-512 pipelines bolted on?

Anyway, the original Atom microarchitecture, Bonnell, had SMT-2:

https://en.wikichip.org/wiki/intel/m...ctures/bonnell

Saltwell followed in this respect, also remaining dual-issue in-order.

https://en.wikichip.org/wiki/intel/m...l#Architecture

However, then Silvermont dropped SMT and went out-of-order.

https://en.wikichip.org/wiki/intel/m...Multithreading

This has remained true of every generation, since (Airmont, Goldmont, Goldmont+, Tremont, and now Gracemont).

BTW, Wikipedia lists a "Grand Ridge" with no other details yet for Gracemont.

Well, it sounds like a successor to Snow Ridge, which is something of a specialty processor for the 5G basestation market. I've not found Snow Ridge boards available for purchase by the general public.

My hope is that Intel puts E-cores in something like the next installment of the Xeon D, which was originally conceived as an efficiency-focused cloud server variant. The Skylake-based 2nd generation kind of dropped the whole efficiency thing, but hopefully it'll come back with E-cores.

Lakefield was an aberration of a product that used 3D stacking and was too expensive.

Was it an aberration or simply a sign of things to come? Intel would have us believe the latter. And yes, putting that much cutting-edge tech in a rather limited-volume product is not the recipe for a low price. But, I'm sure Intel learned some things from doing it that will influence future stacked/hybrid CPUs.

It just seems to me that 1+4 makes more sense than ever putting out another 4-core Atom, especially if it can target the same 6 Watt TDP. And it could use the "bad" 2+8/96EU dies.

I think there won't be nearly enough of those dies with defects that keep them from being sold in a higher product tier. Remember the typical Chromebook is a high-volume, low-margin product. They're going to need lots of cheap silicon, to match.

However, you could be right. Maybe competitive fears from the ARM camp pushes them to go with a 1+4 configuration. I'm reasonably certain the iGPU won't be larger than 32 EU, max (probably with only 16 EUs, at the low end). Given that's the config in Alder Lake desktop CPUs, it should be decent for base-spec Chromebooks.

[coder]

I was curious about this as well so when the first die shots were published I spent a bit of time with die size info (for scaling) and a tape measure.

Cool. Thanks for sharing!

might have to measure it again this weekend just to be sure.

I'm sure others have. Probably just a search over at the Real World Tech forums would turn up the figures.

https://www.realworldtech.com/forum/?roomid=1

[kylew77]

Another thought would be to hunt for a deal on a 4-core Tiger Lake laptop. Tiger Lake is fully decent, better than any Gracemont-based CPU, and has a Xe iGPU. After the holidays pass and Alder Lake laptops hit the market, maybe there could be some deals on some Tiger Lakes?

Same general idea applies to AMD-based laptops, BTW.

That is a good idea. I also think a good idea is to see how many business dump gen 7 Intel business laptops because they can't run Windows 11.