What should the CPU usage be of a fully-loaded CPU that has been throttled?

Re:What should the CPU usage be of a fully-loaded CPU that h... by waterhouse on Saturday July 03, 2021 @11:57PM (#27727126)

Hmm, different workloads will have different mixes of instructions, which will take very different amounts of time per instruction (e.g. a chain of uncached memory lookups vs a tight loop of register-register arithmetic). If you had two instances of the same workload, and one was throttled, then yes, you could compare instructions per unit time. But comparing prime95 vs the other benchmark is likely misleading.

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Re:What should the CPU usage be of a fully-loaded CPU that h... by tayo42 on Sunday July 04, 2021 @01:17AM (#27727399)

Yeah that would be the thing to prove that prime95 is going through more instructions so the cpu runs hotter

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Re:What should the CPU usage be of a fully-loaded CPU that h... by waterhouse on Sunday July 04, 2021 @02:17AM (#27727617)

I see. But I expect that some instructions cost more (i.e. generate more heat) than others. Someone mentions AVX instructions, for example; presumably 1 million AVX-512 fused-multiply-add instructions cost a lot more than 1 million loads (we can probably arrange for the right proportion of loads to hit a CPU cache vs. go to main memory, so that they end up taking the same time). Even without AVX, I imagine things like 64-bit integer divisions or CRC32 instructions cost more than loads or stores, though I don't know by how much.

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Re:What should the CPU usage be of a fully-loaded CPU that h... by tayo42 on Monday July 05, 2021 @03:22PM (#27741086)

oh that makes sense, i guess that would be another aspect to measure

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