Does anyone here know about potentially enabling AVX-512 on Intel 12gen Alder Lake (p-cores maybe not fused off?)
Does anyone here know about potentially enabling AVX-512 on Intel 12gen Alder Lake (p-cores maybe not fused off?)
This is a reference for the situation:
https://www.tomshardware.com/news/intel-nukes-alder-lake-avx-512-now-fuses-it-off-in-silicon
Basically some Alder's had the instruction available. I would like to check if my comp has the possibility. It is not in the bootloader. Maybe there is a way in KeyTool or another way? I don't know if I would need to set affinity or if the CFS has a way to detect software running with the instruction and keep it running on P cores.
I'm mainly looking to try to enable this for the largest LLMs I am running. llama.cpp is looking for this instruction and subset already.
This makes me really dislike Intel. Why even use a fuse? Just rip it out of the silicon. Has the fuse thing been confirmed? Sounds like bs to me
4Speculatively, I think it has more to do with CPU schedulers in kernels. Junk like windows is super inflexible when it comes to the kernel. Like Windows 11 had to be made just because of the Intel asymmetric cores. Changing the scheduler in W10 just wasn't viable. Likely having Alder different makes issues because Microsoft is so inflexible with their tiny OS.
I don't know how Linux is handling the scheduler for intel exactly. I've watched most of the Linux Plumbers conference about the changes to the scheduler from 2021, but I don't recall details about this.
People saying all it takes is disabling the efficiency cores hints that it is a scheduler issue though. I remember someone mentioning that the way cores get spun up and the time it takes to get to full speed is complicated and that management overhead was required, so I'm not sure if the scheduler is the only factor, but I think it is likely the primary.
I'm hoping someone comes along that can identify the mechanism that detects the available instructions and how this can be tested or altered in practice.
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Back when it worked, you just needed to disable the e cores in the bios.
2I wonder if the kernel parameters for CPU isolation were set, if it would enable this.
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