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> so anyone interested can reproduce the results themselves.

Weird reasoning.

You already caught our attention with your article. But not everyone has the time or means to go and re-do the tests.

However such information is really important to surface when making infra decisions. And if one of the brain cells pops up and says something about 20-80% perf improvement VS there were some perf improvements - which would be more convincing to research the topic when the time comes for the reader to benefit from your research?

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You likely tripped over a difference in power management profiles (and capabilities) between Intel and ARM.

You're testing "variability" and latency, and you even mention that "modern Intel CPUs tend to ramp frequency..." but entirely neglect to mention which specific Windows Power Profile you were using.

Fundamentally, you're benchmarking a server operating system on laptops and/or desktop-class hardware, and not the same spec either. I.e.: you're not controlling for differences in memory bandwidth, SSD performance, etc...

Even on server hardware the power profiles matter! A lot more than you think!

One of my gimmicks in my consulting gig is to change Intel server power settings from "Balanced" to "Maximum Performance" and gloat as the customer makes the Shocked Pikachu face because their $$$ "enterprise grade server" instantly triples in performance for the cost of a button press.

Not to mention that by testing this in VMs, you're benchmarking three layers: The outer OS (and its power management), the hypervisor stack, and the inner guest OS.

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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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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.

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

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Agreed. Not to mention NVME SSD throttle pretty quickly due to heat too.
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