[raverbashing]

FP matters (especially with SIMD)

It matters to image/video/audio processing

It matters to simulations

It matters to 3D models/rendering

It matters to games

So it's not "just benchmarks", people actually want to do stuff with it

Sure, AVX512 might not be the greatest way of doing it, and it might be better to just make the existing instructions go faster, that might work

[qayxc]

It's a matter of perspective.

Back in the day, CPUs didn't come with FPUs and the latter were optional co-processors.

The idea in the x86-world always was to "outsource" special requirements to dedicated hardware (FP co-processors, GPUs, sound cards, network cards, hardware codec cards, etc.), instead of putting them on the CPU package (like ARM-based SoCs).

So it's different philosophies entirely - tightly integrated SoCs vs versatile and flexible component-based hardware.

It's The One Ring ([ARM-based] SoCs) vs freedom of choice and modularity (PC). If I don't do simulations or 3d-modelling/rendering, I am free to choose a cheap display adapter without powerful 3D-acceleration and choose a better audio interface instead (e.g. for music production).

The SoC approach forces me to buy that fancy AI/ML-accelerator, various video codecs, and powerful graphics hardware with my CPU regardless of my needs, because the benevolent system provider (e.g. Apple) deems it fit for all...

Torvalds is just old-school in that he prefers freedom of choice and the "traditional" PC over highly integrated SoCs.

[raverbashing]

FP coprocessors "only" existed because the processes weren't advanced enough to have them inside the chip, but they were a natural extension (they were married to the instruction set of the chip - it wasn't a product, it was a feature)

At the old days there were minor competitors to the x87 family that died quickly. (For reference: https://en.wikipedia.org/wiki/X87#Manufacturers )

For the rest yeah, it kinda makes sense to have them customizable.

[pjmlp]

> The idea in the x86-world always was to "outsource" special requirements to dedicated hardware

Actually the Atari and Amigas were there first, that was PC catching up with their multimedia capabilities.

[rumanator]

> So it's not "just benchmarks", people actually want to do stuff with it

IIRC when bulldozer was released and Intel's propaganda machine started spewing stories about how AMD core count was fake because two cores shared a FP unit, there was a flurry of scientific papers on the subject.

IIRC, it was determined that even the hot path of FP-intensive code only executed a single FP ops for each 7 non-FP operations. To put it differently, between each FP op all code has to execute ops to move data around.

Consequently, bulldozer's FP benchmarks scaled linearly wrt cores because even when multiple cores had to share a FP unit to run FP operations, they were so relatively scarce even in number-crunching applications that cores didn't blocked, thus overall performance was not affected.

That's the relevance of FP in real-world benchmarks.