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Comment by eek2121 | Hacker News Reader

Keep in mind that a big part of the huge jump in recent chips was that GB6 added support for SME, and to my knowledge, no app uses SME as of yet. GB5 is a better benchmark for all these chips for this reason.

The actual IPC increase and perf/clock of these chips excluding SME specific acceleration is MUCH smaller.

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I've benchmarked these myself on things like my project's build time on M1, M2 and M3 and I did see similar gains. So I disagree from experience.

I'm not sure what you're talking about. Any app compiled using LLVM 17 (2023) can use SME directly and any app that uses Apple's Accelerate framework automatically takes advantage of SME since iOS 18/macOS 15 last year.

Most apps do not use Apple’s Accelerate framework.

What do you base this on? I use it in all my products and I don't see why any performance-sensitive dev outfit wouldn't at least consider using it.

Most dev outfits are not performance-sensitive

The the whole benchmark discussion becomes moot, doesn't it?

Benchmarking a processor for real-world usage is definitely something you can do.

Benchmarking a processor for "app written by someone who disregards performance" is something you can do, but it's a bit of a pointless exercise; no processor will ever keep up with developers ability to write slow code.

An important question people care about is "will my day to day computing improve with the new processor?".

Of course. And these are CPU vector instructions, so the saying "The wider the SIMD, the narrower the audience" applies.

But ultimately with a benchmark like Geekbench, you're trusting them to pick a weighting. Geekbench 6 is not any different in that regard to Geekbench 5 – it's not going to directly reflect every app you run.

I was really just pointing out that the idea that "no" apps use SME is wrong and therefore including it does not invalidate anything – it very well could speed up your apps, depending on what you use.

SME is just the AMX coprocessor that’s been in Apple chips since 2019. SME made it easier to target the AMX. But it’s been in use and available to developers since 2019.

The point stands that virtually no apps used AMX (either directly or through a framework).

> The point stands that virtually no apps used AMX (either directly or through a framework).

AMX has been present in every M series chip and the A series chips starting with the A13. If you are comparing M series chip scores in Geekbench 6 they are all using it, not just the latest ones.

Any app using Apple's Accelerate framework will take advantage of it.

This isn’t true, I don’t believe GeekBench ever made use of AMX. They do use SME on any Arm-based platform that has it, which up until extremely recently has only been Apple.

Third-party apps sure, but you can guarantee Apple is taking advantage of it fully with any of their work.

Including in authoring all their other frameworks, which are used by many, many apps.

Similar, but not the same. SME is much more powerful than AMX on the pre-M4 cores, and software can target it directly instead of using Apples frameworks. Which means that software is more likely to actually use it (eventually), even if hardly anything does now.

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