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

From: Randy Dunlap
Date: Tue Feb 20 2024 - 18:41:44 EST


{+ tglx]

On 2/20/24 15:19, Mikhail Gavrilov wrote:
> On Mon, Feb 19, 2024 at 2:41 PM Mikhail Gavrilov
> <mikhail.v.gavrilov@xxxxxxxxx> wrote:
>>
>> I installed irqbalance daemon and nothing changed.
>> So who is responsible for irq balancing?
>
> Sorry for the noise. Can anyone give me an answer?
> Who is responsible for distributing interrupts in Linux?
> I spotted network performance regression and it turned out, this was
> due to the network card getting other interrupt. It is a side effect
> of commit 57e153dfd0e7a080373fe5853c5609443d97fa5a.

That's a merge commit (AFAIK, maybe not so much). The commit in mainline is:

commit f977f4c9301c
Author: Niklas Neronin <niklas.neronin@xxxxxxxxxxxxxxx>
Date: Fri Dec 1 17:06:40 2023 +0200

xhci: add handler for only one interrupt line

> Installing irqbalance daemon did not help. Maybe someone experienced
> such a problem?
>

Thomas, would you look at this, please?

A network device and xhci (USB) driver are now sharing interrupts.
This causes a large performance decrease for the networking device.

The thread begins here:
https://lore.kernel.org/lkml/CABXGCsNnUfCCYVSb_-j-a-cAdONu1r6Fe8p2OtQ5op_wskOfpw@xxxxxxxxxxxxxx/


motherboard:
"My motherboard is MPG-B650I-EDGE-WIFI looks like it is related to the
mentioned commit.
https://www.msi.com/Motherboard/MPG-B650I-EDGE-WIFI";

network device:
Network: RTL8125 2.5GbE Controller (rev 05)


thanks.
--
#Randy