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0 pointskllrnohj1y ago0 comments

What are you doing where you see anything remotely close to double-digit-% gains from disabling spectre mitigations?

0 comments

If mitigations include disabling SMT and the workload is compiling code, then the difference is easily in double digits.

kllrnohjOP1y ago

What OS ships the mitigation of disabling SMT by default? Surely they just meant things like the retpoline mitigations in syscalls?

umvi1y ago

my specific use case where I see significant performance improvement is image segmentation pipelines (which involve opencv-style image processing and AI inference). YMMV depending on your CPU I suppose.

iforgot221y ago

Video editing maybe? Which is not going to involve running untrusted code.

kllrnohjOP1y ago

It's not going to hammer on syscalls, either, so it won't have any spectre-related regressions.

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AHTERIX50001y ago

If mitigations include disabling SMT and the workload is compiling code, then the difference is easily in double digits.

kllrnohjOP1y ago

What OS ships the mitigation of disabling SMT by default? Surely they just meant things like the retpoline mitigations in syscalls?

umvi1y ago

iforgot221y ago

Video editing maybe? Which is not going to involve running untrusted code.

kllrnohjOP1y ago

It's not going to hammer on syscalls, either, so it won't have any spectre-related regressions.

j / k navigate · click thread line to collapse