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Re:Arm Announces New Mobile Armv9 CPU Microarchitectures by zibzab on Tuesday May 25, 2021 @12:45PM (#27279126)
X1 is _not_ ARMv9 and there is not even a comparison with M1 on that page.

X2 is not even out yet, you have no idea how it may perform.

Why has every post on HN drift into blindly praising an unrelated product?

Re:Arm Announces New Mobile Armv9 CPU Microarchitectures by klelatti on Tuesday May 25, 2021 @12:56PM (#27279277)
> In terms of the performance and power curve, the new X2 core extends itself ahead of the X1 curve in both metrics. The +16% performance figure in terms of the peak performance points, though it does come at a cost of higher power consumption.

Some idea how the X2 will perform.

Re:Arm Announces New Mobile Armv9 CPU Microarchitectures by GeekyBear on Tuesday May 25, 2021 @01:10PM (#27279456)
>Some idea how the X2 will perform.

If you read on a bit, there is some question that those performance metrics will be seen in the real world, due to existing thermal issues.

> I am admittedly pessimistic in regards to power improvements in whichever node the next flagship SoCs come in (be it 5LPP or 4LPP). It could well be plausible that we wouldn’t see the full +16% improvement in actual SoCs next year.

Re:Arm Announces New Mobile Armv9 CPU Microarchitectures by zibzab on Tuesday May 25, 2021 @02:55PM (#27280813)
In general for moving from v8 to v9, I think 16% is extremely pessimistic.

Removal of aarch32 has huge implications. And this is not limited to CPU but also touches MMU, caches and more that in v8 had to provide aarch32 compatible interfaces. This lead to really inefficient designs (for example, MMU walk which is extremely critical to performance is more than twice as complicated in ARMv8 compared to v7 and v9).

The space saved by removing these can be used for bigger caches, wider units, better branch prediction and other fun stuff.

Finally, note also that the baseline X1 numbers come from Samsung who we all know are worst in class right now. And they are using an inferior process. Let's see what qcomm, ampere and amazon can do with v9.

Re:Arm Announces New Mobile Armv9 CPU Microarchitectures by wmf on Tuesday May 25, 2021 @12:55PM (#27279271)
ARMv8 vs ARMv9 doesn't matter; performance matters. This article is about the X2 so of course we're going to discuss what little information we have.