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crowpier

Member

Registered: 2021-11-04

Posts: 1

Nvidia 495 log spam - full message queue

I ran into the issue mentioned at bugs.kde.org. After anywhere from a few minutes to several hours, depending on the running applications, the journal gets spammed with messages about a full message queue, where sender, interface and member are all "(unset)". For reference here is a copy of the log message taken from the KDE bug post:

dbus-daemon[2006]: [system] Rejected: destination has a full message queue, 0 matched rules; type="error", sender="(unset)" ((bus)) interface="(unset)" member="(unset)" error name="org.freedesktop.DBus.Error.ServiceUnknown" requested_reply="1" destination=":1.38" (uid=1000 pid=2526 comm="/usr/bin/kwin_x11 ")

One user measured that on their machine an unknown/deprecated nvidia.powerd service was requested 27 times a second while an OpenGL application is running.
If you are using an NVIDIA card check your log files, the issue might have gone unnoticed and is increasing your journal logs rapidly, burying useful messages under mountains of spam.

On the nvidia forums people have discussed the issue and already created workarounds.
While there is no updated/fixed driver this workaround seems safe enough to temporarily add to the official nvidia packages, until NVIDIA releases a fixed version.
Following is a copy of the workaround by "user16974" from the NVIDIA forums. On my system I had to create the /etc/dbus-1/system.d/ directory manually and run systemctl reload dbus after creating the nvidia-fake-powerd.conf file.

/etc/dbus-1/system.d/nvidia-fake-powerd.conf

<!DOCTYPE busconfig PUBLIC
 "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
        <policy user="dbus">
                <allow own="nvidia.powerd.server"/>
        </policy>
        <policy context="default">
                <allow send_destination="nvidia.powerd.server"/>
                <allow receive_sender="nvidia.powerd.server"/>
        </policy>
</busconfig>

/etc/systemd/system/nvidia-fake-powerd.service

[Unit]
Description=NVIDIA fake powerd service

[Service]
Type=dbus
BusName=nvidia.powerd.server
ExecStart=/usr/bin/dbus-test-tool black-hole --system --name=nvidia.powerd.server
User=dbus
Group=dbus
LimitNPROC=2
ProtectHome=true
ProtectSystem=full

[Install]
WantedBy=default.target
Alias=dbus-nvidia.fake-powerd.service

Of course once these files are in place, systemd must be reloaded and the service enabled/started:

systemctl daemon-reload
systemctl enable nvidia-fake-powerd.service
systemctl start nvidia-fake-powerd.service
systemctl status nvidia-fake-powerd.service

Last edited by crowpier (2021-11-04 19:34:57)

Mr.Smith1974

Member

From: St. Petersburg, Russia

Registered: 2013-04-13

Posts: 38

Re: Nvidia 495 log spam - full message queue

I have error on start:

× nvidia-fake-powerd.service - NVIDIA fake powerd service
     Loaded: loaded (/etc/systemd/system/nvidia-fake-powerd.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Fri 2021-11-26 16:30:23 MSK; 15s ago
    Process: 2443 ExecStart=/usr/bin/dbus-test-tool black-hole --system --name=nvidia.powerd.server (code=exited, status=1/FAILURE)
   Main PID: 2443 (code=exited, status=1/FAILURE)
        CPU: 9ms

Nov 26 16:30:23 home-desktop systemd[1]: Starting NVIDIA fake powerd service...
Nov 26 16:30:23 home-desktop dbus-test-tool[2443]: failed to take bus name nvidia.powerd.server
Nov 26 16:30:23 home-desktop systemd[1]: nvidia-fake-powerd.service: Main process exited, code=exited, status=1/FAILURE
Nov 26 16:30:23 home-desktop systemd[1]: nvidia-fake-powerd.service: Failed with result 'exit-code'.
Nov 26 16:30:23 home-desktop systemd[1]: Failed to start NVIDIA fake powerd service.

KorvinSilver

Member

Registered: 2018-10-27

Posts: 26

Re: Nvidia 495 log spam - full message queue

I have error on start:

× nvidia-fake-powerd.service - NVIDIA fake powerd service
     Loaded: loaded (/etc/systemd/system/nvidia-fake-powerd.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Fri 2021-11-26 16:30:23 MSK; 15s ago
    Process: 2443 ExecStart=/usr/bin/dbus-test-tool black-hole --system --name=nvidia.powerd.server (code=exited, status=1/FAILURE)
   Main PID: 2443 (code=exited, status=1/FAILURE)
        CPU: 9ms

Nov 26 16:30:23 home-desktop systemd[1]: Starting NVIDIA fake powerd service...
Nov 26 16:30:23 home-desktop dbus-test-tool[2443]: failed to take bus name nvidia.powerd.server
Nov 26 16:30:23 home-desktop systemd[1]: nvidia-fake-powerd.service: Main process exited, code=exited, status=1/FAILURE
Nov 26 16:30:23 home-desktop systemd[1]: nvidia-fake-powerd.service: Failed with result 'exit-code'.
Nov 26 16:30:23 home-desktop systemd[1]: Failed to start NVIDIA fake powerd service.

Have you tried with the nvidia-fake-powerd from AUR? I got the same error when I set it up manually but for some reason with the package it works.

tethys

Member

Registered: 2019-08-13

Posts: 115

Re: Nvidia 495 log spam - full message queue

I was affected by this, it's been 6 months, I looked here, so I thought the problem has been solved. I rolled back the changes and big surprise: the journal was again full of spam (68M in about one hour!). Can somebody confirm that the bug has not been actually solved?