Bug#1011523: systemd-logind: lightdm ignores keyboard input for the first 3 seconds

[Vincent Lefevre]

On 2022-06-24 15:57:22 +0200, Vincent Lefevre wrote:
> On 2022-05-25 20:43:50 +0200, Yves-Alexis Perez wrote:
> > I don't think there's really code in the display manager to specifically
> > handle keyboards, I'd assume it's in the X part, but I might be wrong.
> 
> The issue could also be in the X server, e.g. in case of a race condition
> whose effects appeared after the upgrade to systemd 251-2.

Well, the X server is not the cause. As said in the Xorg logs:
The server relies on udev to provide the list of input devices.

And the logs show that before the upgrade to systemd 251, the delay
was less than 2 seconds, while after the upgrade to systemd 251,
the delay is now 4 - 7 seconds.

Before:

[    14.784] 
X.Org X Server 1.21.1.3
[    16.597] (II) config/udev: Adding input device DELL Dell USB Entry Keyboard (/dev/input/event2)

[    15.005] 
X.Org X Server 1.21.1.3
[    16.818] (II) config/udev: Adding input device DELL Dell USB Entry Keyboard (/dev/input/event2)

After:

[    11.999] 
X.Org X Server 1.21.1.3
[    15.909] (II) config/udev: Adding input device DELL Dell USB Entry Keyboard (/dev/input/event2)

[     7.688] 
X.Org X Server 1.21.1.3
[    14.644] (II) config/udev: Adding input device DELL Dell USB Entry Keyboard (/dev/input/event2)

Is the kernel stressed because systemd now starts too many services
in parallel?

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Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
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