Originally posted by zyxxel
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What's happening is that you don't understand microarchitecture (maybe you think you do, but you really don't). So you pull the discussion in a direction that you do understand. But, but, but, what about this? It really doesn't make your points valid.
First chapter of H&P tells you about what determines the runtime of a simple process - a trivial equation involving instruction count, IPC, and clock cycle of the processor.
Well, we live in a time where clock frequencies don't really change that much, and even instruction counts between different architectures don't vary that much. What's left is the IPC, which is the big elephant in the room. And yes, over there the difference between something like a Raspberry Pi and a lowly Pentium Gold is remarkable. Because of the microarchitecture, even a Pentium Gold can sustain much higher instruction throughputs than a RPi.
The thing is - it's difficult to understand microarchitecture, so all the BSers focus on details that they can understand, things that are described with simple numbers.
While I don't think you will, you really should read H&P.
And, FWIW, I have a PhD in the topic with research work cited in microprocessor patents.
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