Re: [x86/mce] 7bb39313cd: netperf.Throughput_tps -4.5% regression

From: Borislav Petkov
Date: Tue Jan 19 2021 - 10:36:01 EST


On Tue, Jan 19, 2021 at 11:09:03PM +0800, Feng Tang wrote:
> Yes, that can happen. I started a 4 tasks netperf on a 4C/8T KBL desktop,
> and also saw around 2% improvement. Both the kernel config and the
> platform matters.

Oh great. ;-\

> For the performance changes I have checked, sometimes the change can be
> reproduced on platforms of different generations (the exact delta number
> may differs), sometimes it can only be reproduced on one specific platform,
> like some old generation, or special one like Xeon Phi.

Probably because that Xeon Phi thing is not as powerful cache-wise as
some newer ones which have bigger caches and smarter hw prefetchers,
etc.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette