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I'll leave the results >> of testing on a dual socket 3rd Generation EPYC System (2 x 64C/128T) >> running in NPS1 mode below. >> >> tl;dr >> >> - Hackbench with medium load, tbench when overloaded, and DeathStarBench >>   are not a fan of EEVDF so far :( > > FWIW, there are more tbench shards lying behind EEVDF than in front. > > tbench 8 on old i7-4790 box > 4.4.302 4024 > 6.4.11 3668 > 6.4.11-eevdf 3522 > I agree, but on servers, tbench has been useful to identify a variety of issues [1][2][3] and I believe it is better to pick some shards up than leave them lying around for others to step on :) Casting aside tbench, there are still more workloads that have regression and it'll be good to understand which property of those don't sit well with EEVDF. [1] https://lore.kernel.org/lkml/c50bdbfe-02ce-c1bc-c761-c95f8e216ca0@amd.com/ [2] https://lore.kernel.org/lkml/20220921063638.2489-1-kprateek.nayak@amd.com/ [3] https://lore.kernel.org/lkml/80956e8f-761e-b74-1c7a-3966f9e8d934@linutronix.de/ > I went a-hunting once, but it didn't go well. There were a couple > identifiable sched related dips/recoveries, but the overall result was > a useless downward trending mess. > > -Mike -- Thanks and Regards, Prateek