Extreme performance GRUB setting

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Extreme performance GRUB setting

Kernel boot parameters can be used to optimize the behavior of the Linux kernel for specific hardware configurations and improve system performance. In particular, certain kernel boot parameters can be used to achieve low latency and jitter, which are critical for real-time applications.

For example, the isolcpus parameter can be used to isolate CPU cores from the scheduler, preventing any tasks from being scheduled on those cores. This can improve system responsiveness and reduce latency. Similarly, the nohz parameter can be used to enable the kernel's tickless idle feature, which reduces the number of timer interrupts generated by the kernel. This can further reduce system latency and improve system performance.

Other kernel boot parameters, such as clocksource=tsc and tsc=perfect, can be used to improve system performance on certain hardware platforms. For example, the TSC clocksource can provide more accurate timing information, which is important for real-time applications.

Overall, the benefit of using kernel boot parameters is that they can be used to fine-tune the Linux kernel for specific hardware configurations and improve system performance. By using the right combination of parameters, you can achieve low latency and jitter, which are critical for real-time applications.

However, it is important to use kernel boot parameters judiciously, as inappropriate use can lead to system instability and reduced performance. It is recommended to consult the documentation and seekexpert advice before making any changes to kernel boot parameters. In particular, some parameters may impact the stability of certain applications or limit overall system performance if not used appropriately. Therefore, it is important to carefully consider the specific hardware configuration and use case before making any changes to the kernel boot parameters. It is also a good practice to test the system thoroughly after making any changes to ensure that they have the desired effect and do not cause any unexpected issues.

With this setting 

text 3 biosdevname=0 net.ifnames=0 clocksource=tsc tsc=perfect noapic isolcpus=0 processor.max_cstate=1 amd_idle.max_cstate=1 nohz=on isolcpus=nohz,domain,1-3 nohz_full=1-3 rcu_nocbs=1-3 no_balance_cores=1-3
  • biosdevname=0: Disables predictable network interface names based on BIOS-provided information.
  • net.ifnames=0: Disables predictable network interface names based on firmware, location, and topology information.
  • clocksource=tsc: Specifies the clocksource for the kernel to use, in this case the Time Stamp Counter (TSC).
  • tsc=perfect: Enables the kernel to use the TSC as the clocksource, with the assumption that the TSC is perfectly synchronized across all CPUs.
  • noapic: Disables the Advanced Programmable Interrupt Controller (APIC) in the kernel.
  • isolcpus=0: Isolates CPU 0 from the scheduler, preventing any tasks from being scheduled on that CPU.
  • processor.max_cstate=1: Limits the maximum CPU idle state to C1, which disables certain CPU power-saving features.
  • amd_idle.max_cstate=1: Limits the maximum CPU idle state to C1 for AMD processors.
  • nohz=on: Enables the kernel's tickless idle feature, which improves power efficiency by reducing the numberof timer interrupts that the kernel generates.
  • isolcpus=nohz,domain,1-3: Isolates CPUs 1-3 from the scheduler and also enables the tickless idle feature for those CPUs.
  • nohz_full=1-3: Enables full tickless idle mode for CPUs 1-3.
  • rcu_nocbs=1-3: Specifies the CPUs that should not participate in the RCU (Read-Copy-Update) mechanism, which is used for synchronization in the kernel.
  • no_balance_cores=1-3: Prevents the kernel from trying to balance the load across CPUs 1-3.