Most time, we need to tune system parameters to achieve better performance but what the general parameters to be tuned in Linux systems.
I think you may want to add following parameters to Kernel boot (/etc/default/grub) parameters
intel_idle.max_cstate=0 processor.max_cstate=0 idle=poll intel_pstate=disable
At the same time, you may also want to shutdown/open Pause Loop Exiting (PLE). See [2] [3] for more details about PLE, and see [1] [4] for more details about Intel C-States and P-States.
How to Shutdown PLE:
sudo rmmod kvm_intel
sudo modprobe kvm_intel ple_gap=0 ple_window=0
cat /sys/module/kvm_intel/parameters/ple*
How to turn on PLE:
sudo rmmod kvm_intel
sudo modprobe kvm_intel
cat /sys/module/kvm_intel/parameters/ple*
References
[1] https://stackoverflow.com/questions/12111954/context-switches-much-slower-in-new-linux-kernels
[2] https://www.google.com/patents/US9021497
[3] https://surriel.com/system/files/riel_t_1620_kvm_performance.pdf
[4] https://haypo.github.io/intel-cpus.html
IDLE=POLL
means when vCPU is idle CPU will execute No Op
instruction like spin-lock does. This will trigger PLE if PLE is turned on.
Also see this slides for more details about P-States.