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> Yes, there are workloads where huge-pages do not bring any measurable benefit

I really doubt it, except of course workloads where you just use a trivial amount of memory to begin with. In systems I've seen, anywhere from 5% to 15% of the CPU time is spent waiting for TLB misses. It's obvious then that huge pages can be hugely beneficial if properly used; by definition they hugely relieve TLB pressure.

You can of course end up in situations where transparent TLB scanning is worse than nothing, but that's exactly why I pointed out there's a variety of ways to use huge pages.



You don't seem to understand the idea that CPU spending time on TLB misses and at the same time seeing no measureable effects in E2E performance because much larger bottleneck is elsewhere can be both valid simultaneously. In database kernels with large and unpredictable workloads, high IO and memory footprint, this is certainly easy to prove.


I think you're moving the goalpost here. There's a measurement improvement to CPU usage. You're over-provisioned on CPU and don't care. Fine.




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