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Thu, 16 Nov 2023 08:37:39 -0800 (PST) On 10.11.2023 15:56, Sean Christopherson wrote: > On Thu, Nov 09, 2023, Dongli Zhang wrote: >> Hi Sean, >> >> On 11/9/23 18:28, Sean Christopherson wrote: >>> base-commit: ef1883475d4a24d8eaebb84175ed46206a688103 >> May I have a silly question? >> >> May I have the tree that the commit is the base? I do not find it in kvm-x86. >> >> https://github.com/kvm-x86/linux/commit/ef1883475d4a24d8eaebb84175ed46206a688103 > It's kvm-x86/next (which I failed to explicitly call out), plus two PMU series > as mentioned in the cover letter. > > https://lore.kernel.org/all/20231103230541.352265-1-seanjc@google.com > https://lore.kernel.org/all/20231110021306.1269082-1-seanjc@google.com Hi Sean, i have tested my testcase on your patchset, results look impressive, thank you for your work! Note, for AMD node PMU totally disabled case gave a bit worse results on kvm-next kernel vs stock latest mainstream. The difference is tiny though. *AMD node*: CPU: AMD Zen 3 (three!): AMD EPYC 7443P 24-Core Processor ----------------------------------------------------------------------------------------- | Kernel | CPUID rate | ----------------------------------------------------------------------------------------- | stock ms 6.6.0+ (commit 305230142ae0) | 1360250 | | stock ms 6.6.0+ + kvm.enable_pmu=0 | 1542894 (+13.4%) | | kvm-next ms 6.6.0+ + patches from Sean + kvm.enable_pmu=1 | 1498864 | | kvm-next ms 6.6.0+ + patches from Sean + kvm.enable_pmu=0 | 1526396 (+1.84%) | ----------------------------------------------------------------------------------------- *Intel node*: CPU: Intel(R) Xeon(R) E-2136 CPU @ 3.30GHz ----------------------------------------------------------------------------------------- | Kernel | CPUID rate | ----------------------------------------------------------------------------------------- | stock ms 6.6.0+ | 1431608 | | stock ms 6.6.0+ + kvm.enable_pmu=0 | 1553839 (+8.5%) | | kvm-next ms 6.6.0+ + patches from Sean + kvm.enable_pmu=1 | 1559365 | | kvm-next ms 6.6.0+ + patches from Sean + kvm.enable_pmu=0 | 1582281 (+1.5%) | ----------------------------------------------------------------------------------------- Note: in order to disable PMU completely i used "kvm" module "enable_pmu=0" option (not used KVM_PMU_CAP_DISABLEthis time). Hope that helps. -- Best regards, Konstantin Khorenko, Virtuozzo Linux Kernel Team