Bug 409074 - System load viewer sometimes sees no load while there is some
Summary: System load viewer sometimes sees no load while there is some
Status: RESOLVED WORKSFORME
Alias: None
Product: kdeplasma-addons
Classification: Plasma
Component: systemloadviewer (show other bugs)
Version: 5.14.5
Platform: Other Linux
: NOR normal
Target Milestone: ---
Assignee: Plasma Bugs List
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2019-06-23 12:59 UTC by Ralf Jung
Modified: 2020-11-15 04:33 UTC (History)
0 users

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
A screenshot demonstrating the issue (299.47 KB, image/png)
2019-06-23 12:59 UTC, Ralf Jung
Details

Note You need to log in before you can comment on or make changes to this bug.
Description Ralf Jung 2019-06-23 12:59:09 UTC
Created attachment 121093 [details]
A screenshot demonstrating the issue

SUMMARY
When switching the system load viewer to show per-CPU load, during a long compilation session (where there's always load on at least one core), the laod seems to regularly drop to 0 according to the load viewer. Watching htop at the same time shows that there is always load, though.


STEPS TO REPRODUCE
0. Configure system load viewer to show per-CPU load and a high update frequency (e.g. 0.5s). The issue also happens with 2s, but is easier to observe with higher frequencies.
1. Start a long build.
2. Start htop.
3. Watch htop and the load viewer.

OBSERVED RESULT
They should show roughly the same thing.

EXPECTED RESULT
The load viewer frequently claims no load when there actually is plenty. I attached a screenshot. The system load viewer widget is marked in the bottom-left corner.  You can't see it because it shows 0 load.

SOFTWARE/OS VERSIONS
Operating System: Debian GNU/Linux 10
KDE Plasma Version: 5.14.5
Qt Version: 5.11.3
KDE Frameworks Version: 5.54.0
Kernel Version: 4.19.0-5-amd64
OS Type: 64-bit
Processors: 8 × Intel® Xeon® CPU E3-1505M v5 @ 2.80GHz
Memory: 15,5 GiB of RAM


ADDITIONAL INFORMATION
Comment 1 Ralf Jung 2019-06-23 13:05:52 UTC
Interestingly, I have never seen this happen when showing just one bar for the entire CPU load. So this seems to be something about the per-CPU-load measurement.
Comment 2 Nate Graham 2020-10-16 02:16:24 UTC
Is this still an issue or relevant with the new System Monitor applet in Plasma 5.19 and beyond?
Comment 3 Bug Janitor Service 2020-10-31 04:33:34 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 4 Bug Janitor Service 2020-11-15 04:33:42 UTC
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!