https://bugs.kde.org/show_bug.cgi?id=527808
Bug ID: 527808
Summary: powerdevil "(i2c_detect_x37) Extra x37 sleep" delays
startup of autostart applications
Classification: Plasma
Product: plasmashell
Version First 6.7.5
Reported In:
Platform: Fedora RPMs
OS: Linux
Status: REPORTED
Severity: normal
Priority: NOR
Component: Startup process
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected]
Target Milestone: 1.0
DESCRIPTION
On my system, when logging into the Plasma Wayland session, powerdevil's DDC
initialization seems to delay it reporting to systemd that the service is
ready, leading to the login sound and autostarted applications being delayed
for several seconds.
If I add a systemd override to set the POWERDEVIL_NO_DDCUTIL=1 environment
variable for plasma-powerdevil.service, then powerdevil loads almost instantly
and there's no longer any delay in autostarting applications.
I'm not sure if there are known issues with DDC on my hardware. The system is
AMD X870E motherboard + Nvidia 4090 GPU (driver version 615.78.08) + a single
display connected over HDMI (LG C1 TV). Assuming there's something
fundamentally slow about DDC in this hardware setup, would it be possible for
powerdevil to report that it's ready while the DDC startup logic runs in the
background?
The following is an example of the delay on my system (from `journalctl --user
-b -1 -u plasma-powerdevil`). plasma-workspace.target isn't reached until the
"Started plasma-powerdevil.service - Powerdevil" line and no autostarted
applications begin running until that point (== 6 second delay).
Oct 25 13:55:58 cxl-desktop-1 systemd[3125]: Starting
plasma-powerdevil.service - Powerdevil...
Oct 25 13:55:58 cxl-desktop-1 org_kde_powerdevil[3659]: Starting
libddcutil. library built Jul 15 2026 at 00:00:00.
stdout_stderr_redirected=true
Oct 25 13:55:58 cxl-desktop-1 org_kde_powerdevil[3659]: Initializing
libddcutil. ddcutil version: 2.2.1, shared library:
/usr/lib64/libddcutil.so.5.3.0
Oct 25 13:55:58 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] Options
passed from client:
Oct 25 13:55:58 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] Applying
combined libddcutil options:
Oct 25 13:55:58 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659]
(i2c_detect_x37) Extra x37 sleep: Sleeping for 2000 milliseconds
Oct 25 13:56:00 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659]
(i2c_detect_x37) Extra x37 sleep: Sleeping for 2000 milliseconds
Oct 25 13:56:02 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659]
(i2c_detect_x37) Extra x37 sleep: Sleeping for 2000 milliseconds
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: Library
initialization complete.
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: Watching for DPMS
state changes unimplemented
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] Watching
for DPMS state changes unimplemented
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] Watching
for display connection changes, resolved watch mode = Watch_Mode_Xevent, poll
loop interval = 100 millisec
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659]
extra_stabilization_millisec: 0,
stabilization_poll_millisec: 100
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] libddcutil
recheck thread 0x55aec20d20a0 started
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3659] libddcutil
watch thread 0x55aec20cb6a0 started
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: [ 3959]
(dw_recheck_displays_func) Recheck interval: Sleeping for 200 milliseconds
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]:
org.kde.powerdevil.chargethresholdhelper.getthreshold failed "Charge thresholds
are not supported by the kernel for this hardware"
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]:
org.kde.powerdevil.backlighthelper.brightness failed
Oct 25 13:56:04 cxl-desktop-1 systemd[3125]: Started
plasma-powerdevil.service - Powerdevil.
Oct 25 13:56:04 cxl-desktop-1 org_kde_powerdevil[3659]: Handle button
events action could not check for screen configuration
Oct 25 13:56:05 cxl-desktop-1 org_kde_powerdevil[3659]:
org.kde.powerdevil.chargethresholdhelper.getthreshold failed "Charge thresholds
are not supported by the kernel for this hardware"
Oct 25 13:56:05 cxl-desktop-1 org_kde_powerdevil[3659]: Failed to register
with host portal QDBusError("org.freedesktop.portal.Error.Failed", "Could not
register app ID: App info not found for 'org.kde.org_kde_powerdevil'")
Oct 25 13:56:05 cxl-desktop-1 org_kde_powerdevil[3659]: Failed to register
with host portal QDBusError("org.freedesktop.portal.Error.Failed", "Could not
register app ID: Connection already associated with an application ID")
SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 45
KDE Plasma Version: 6.7.5
KDE Frameworks Version: 6.31.0
Qt Version: 6.11.2
Kernel Version: 7.2.11-300.fc45.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 32 × AMD Ryzen 9 9950X3D 16-Core Processor
Memory: 96 GiB of RAM (93.9 GiB usable)
Graphics Processor: NVIDIA GeForce RTX 4090
--
You are receiving this mail because:
You are watching all bug changes.
