On: Analyzing Core I9-9900K performance with Spectre a...

[duxup]

Forgive me as I'm nowhere near knowledgeable in CPUs or such so my terminology will be way off.

For any CPU designed with the expectation of using the old method of memory access prediction without any protections... can we expect they'll ever show a significant performance recovery?

I guess I always assumed the answer was no.

[ethbro → duxup]

(Someone please correct me if I'm wrong) Without adding additional hardware, likely not significant.

The way you avoid some of the impacted scenarios (at modest performance impact) is with additional hardware or microarchitecture changes.

Basically, the task is 'Ensure processor state, as observed by another process, never changes because of speculative execution branches.'

Which is a high bar to meet, especially if you want to simultaneously optimize your execution unit utilization.