Xfce4-sensors-plugin displays wrong core temperatures in panel until sensor viewer or sensors plugin window are opened

[spike speigel]

Xfce4-sensors-plugin displays wrong core temperatures in panel until sensor viewer or sensors plugin window are opened. When the windows are opened, the user clearly sees the temperatures do not match, and are off by ~20-30 degrees Celsius. If those windows are opened and the user browses through the tabs, the panel readout finally adjusts to match the accurate temperatures displayed in the windows.

I'm experiencing this issue on a Dell XPS 13 9360 running Xubuntu/Ubuntu 17.10 with xfce4-sensors-plugin v1.2.6-1

I'm attaching before and after screenshots.

[spike speigel (frail-knight)]

Created attachment 7610
Panel_Displaying_Wrong_Core_Temps

Xfce4-sensors-plugin displays wrong core temperatures in panel until sensor viewer or sensors plugin window are opened. When the windows are opened, the user clearly sees the temperatures do not match, and are off by ~20-30 degrees Celsius. If those windows are opened and the user browses through the tabs, the panel readout finally adjusts to match the accurate temperatures displayed in the windows.

I'm experiencing this issue on a Dell XPS 13 9360 running Xubuntu/Ubuntu 17.10 with xfce4-sensors-plugin v1.2.6-1

I'm attaching before and after screenshots.

[spike speigel (frail-knight)]

Created attachment 7611
Panel_Displaying_Right_Core_Temps

[Fabian Nowak (timystery)]

Although I see your problems, I must tell you that
1. The xfce4-sensors standalone viewer does not interfere with the plugin
2. the ACPI values from file system and the values reported by libsensors3/4 are used; not detected on my own
3. I have similar problems with the coretemp values being 20-30K off the real value in comparison to ACPI, thinkpad and all the others.

You can try to
- check the update interval to something between 1 and 10 seconds
- run "sensors" on the command line, which displays just what libsensors4 delivers.

In order to tackle the problem more deeply, you could try running "sensors" just after system startup when the values in the sensors plugin are supposed to be too high. The values from the command line should be reported on the panel as well.

Hope that helps and that there aren't any real problems neither in the plugin nor in the libraries.

[spike speigel (frail-knight)]

It is all very strange. I think the system is fine. Just now the panel reported temps ~34 degrees C while the standalone viewer was reporting ~90 degrees C. Then I merely toggled between Celsius and Fahrenheit a few times and both the panel and standalone viewer then agreed on values ~56 degrees C. So neither the panel nor the standalone viewer were displaying the proper values before I toggled temperature scale.

If they should both be reading the same value from ACPI or libsensors, why would they both be different from each other AND wrong??

Perhaps it is a timing thing. I will watch for it a while on each boot.

[spike speigel (frail-knight)]

Hi Fabian,

At the moment the panel and standalone viewer are displaying the temps fine, but here are some results from your queries:

~$ apt-cache policy libsensors4
libsensors4:
  Installed: 1:3.4.0-4
  Candidate: 1:3.4.0-4
  Version table:
 *** 1:3.4.0-4 500
        500 http://us.archive.ubuntu.com/ubuntu artful/main amd64 Packages
        100 /var/lib/dpkg/status

~$ xfce4-sensors -V
Xfce4 Sensors 1.2.6

~$ sensors
coretemp-isa-0000
Adapter: ISA adapter
Package id 0: +52.0°C (high = +100.0°C, crit = +100.0°C)
Core 0: +51.0°C (high = +100.0°C, crit = +100.0°C)
Core 1: +50.0°C (high = +100.0°C, crit = +100.0°C)

acpitz-virtual-0
Adapter: Virtual device
temp1: +25.0°C (crit = +107.0°C)

pch_skylake-virtual-0
Adapter: Virtual device
temp1: +49.0°C

[Fabian Nowak (timystery)]

OK, so for now as a hint:

the output from ~$ sensors are the values that libsensors4 delivers to the standalone app and the panel plugin as well.

With rather old computers like mine, having fast/small update intervals impacts the system and thus can increase the temperature very fast. With a value of "1 s", system load of the panel plugin is between 4.x % and 11.x %, thereby increasing system temperature all the time, which is why I normally have "60 s". In contrast, or in addition, having slow/high update intervals in the panel plugin and then opening the app will immediately show the newest values only in the app, with large differences to those seen in the plugin.

Hitting the point when the panel plugin also updates the values you *should* have the same temps, just as with ~$ sensors. So maybe you can adjust the panel plugin to something like "10 s", then open the app after more than 10 s, and the values will hopefully be equal.

Toggling between the two available scales will update the values immediately in wherever you do that. However, the app and the plugin do not relate to each other! They only use the same library "libxfce4sensors" to interface libsensors4, ACPI, hddtemp and Nvidia.

HTH

Fabian

[Alcyone-9 (alcyone-9)]

I had similar issue with all readings first not updating and then disappearing after a while — and readings updated only by opening xfce4-sensors-plugin settings. Solved by two things:
1) Removed xfce4-sensors-plugin from panel settings list of items in panel (I don't know exact names in English, because I use Finnish).
2) From directory ~/.config/xfce4/panel removed files .xfce4-sensors-plugin-*.rc and xfce4-sensors-plugin-*.rc (notice the dot in front of the first one, I had one of those configs).
Then just readded the sensors plugin to the panel and did all settings again.

[Fabian Nowak (timystery)]

Yes, although I can't provide evidence for what happened exactly, your settings must have had Fahrenheit in between. Deleting all old config files while the plugin is not loaded or the entire panel not running at all, will probably fix your troubles.