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From: Thomas Gleixner <tglx@linutronix.de>
To: mikhail.v.gavrilov@gmail.com, Mathias Nyman
 <mathias.nyman@linux.intel.com>, Linux regressions mailing list
 <regressions@lists.linux.dev>
Cc: "Christian A. Ehrhardt" <lk@c--e.de>, niklas.neronin@linux.intel.com,
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Subject: Re: This is the fourth time I've tried to find what led to the
 regression of outgoing network speed and each time I find the merge commit
 8c94ccc7cd691472461448f98e2372c75849406c
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Date: Tue, 27 Feb 2024 18:23:51 +0100
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On Tue, Feb 27 2024 at 22:08, mikhail.v.gavrilov@gmail.com wrote:
> On Mon, 2024-02-26 at 19:09 +0100, Thomas Gleixner wrote:
>> we don't have any information about the overall workload,
>
> During measurements nothing was running except iperf3

Ok.

> I don't know how else to help you. What information to provide.

If we want to understand why CPU0 is problematic, then you need to use
tracing to capture what's going on on CPU0 vs. other CPUs.

> About repeatability my "unlucky" scenario.
> I have two MSI MPG B650I EDGE WIFI motherboards and this problem
> happened both at the same time.

Sure. The probe order and the number of interrupts are probably exactly
the same. As the spreading algorithm is very basic, it will result in
exactly the same setup for both.

> It seems the problem has always been there, we just never noticed it.

Exactly.

Thanks,

        tglx