"Tests were done on Ubuntu 18.04 LTS x86_64 with its default Linux 4.15 kernel."
It would be interesting to see if there is any actual difference between the kernel disabling HT and the bios disabling HT. Difference being, that HT in software has overhead, so if you don't compile the HT software in the kernel, perhaps the kernel can work slightly better since the scheduler has different expectations?
CONFIG_SCHED_SMT:
│ SMT scheduler support improves the CPU scheduler's decision making
│ when dealing with Intel Pentium 4 chips with HyperThreading at a
│ cost of slightly increased overhead in some places. If unsure say
│ N here.
│ Symbol: SCHED_SMT [=n]
│ Type : bool
│ Prompt: SMT (Hyperthreading) scheduler support
│ Location:
│ -> Processor type and features
│ Defined at arch/x86/Kconfig:1009
│ Depends on: SMP [=y]
It would be interesting to see if there is any actual difference between the kernel disabling HT and the bios disabling HT. Difference being, that HT in software has overhead, so if you don't compile the HT software in the kernel, perhaps the kernel can work slightly better since the scheduler has different expectations?
CONFIG_SCHED_SMT:
│ SMT scheduler support improves the CPU scheduler's decision making
│ when dealing with Intel Pentium 4 chips with HyperThreading at a
│ cost of slightly increased overhead in some places. If unsure say
│ N here.
│ Symbol: SCHED_SMT [=n]
│ Type : bool
│ Prompt: SMT (Hyperthreading) scheduler support
│ Location:
│ -> Processor type and features
│ Defined at arch/x86/Kconfig:1009
│ Depends on: SMP [=y]
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