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Comment by jasoneckert

15 hours ago

Both Windows 11 systems are configured with the “High performance” power plan, as are the two Windows Server VMs. In hindsight, I should have included this detail explicitly in the original post instead of only alluding to it.

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jasoneckert

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fulafel  14 hours ago

For others unfamiliar with Windows, according to https://learn.microsoft.com/en-us/windows-server/administrat... "High Performance" entails:

> Processors are always locked at the highest performance state (including "turbo" frequencies). All cores are unparked. Thermal output may be significant.

  • vlovich123  13 hours ago

    This isn’t specific to windows. This is also basically the same terminology Linux uses.

    • fulafel  13 hours ago

      There's no mode spelled the same ("High Performance") - and I don't think Linuxes universally do this:

      > Processors are always locked at the highest performance state (including "turbo" frequencies).

      Unless performance state means something idiosyncratic in MS terminology.

      Normally you'd want to let idle apply power saving measures including downclocking to donate some unused power envelope to busy cores, increasing overall performance.

      But this varies across various Linux based platforms. For example on RHEL (https://docs.redhat.com/en/documentation/red_hat_enterprise_...):

      "throughput-performance:

          A server profile optimized for high throughput that disables power savings mechanisms. It also enables sysctl settings to improve the throughput performance of the disk and network IO.

      accelerator-performance:

          A profile that contains the same tuning as the throughput-performance profile. Additionally, it locks the CPU to low C states so that the latency is less than 100us. This improves the performance of certain accelerators, such as GPUs.

      latency-performance:

          A server profile optimized for low latency and disables power savings mechanisms and enables sysctl settings that improve latency. CPU governor is set to performance and the CPU is locked to the low C states (by PM QoS). "

      Here the latency-performance profile sounds most like the Windows Server mode (but differnet from throughput-performance).

jiggawatts  13 hours ago

Even if you do that, there are firmware-level overrides that most laptops won't allow you to override. If you did, the laptop would melt.

You might be benchmarking the chassis fans more than the CPUs!