debcrafters-packages team mailing list archive

[Eduardo Henrique Silva Teixeira <2112342@xxxxxxxxxxxxxxxxxx>]

Thank you for the feedback — and apologies if the original report came
across as a personal preference rather than a serious technical issue.
This is my first bug report, and I may not have made the core problem
clear enough.

Let me clarify:

The issue is not that the system shuts down too early — the issue is
that it doesn't shut down at all.

When the battery reaches 2% (as per UPower's current default), on
laptops with moderate battery wear (in my case ~64% capacity remaining),
the voltage often drops too quickly for the system to finish the
shutdown or suspend process.

The result is not a graceful power-off, but rather:

1. A complete system freeze on boot screen (photo),
2. A blinking Caps Lock LED, which signals a kernel panic,
3. And sometimes filesystem corruption on the next boot due to unclean unmounting.

This is not a subjective preference — it's a data integrity and system
stability issue.

After changing:

"PercentageAction=5.0"

...the problem was fully resolved. The system now powers off (or hybrid-
sleeps) cleanly and reliably.


Raising PercentageAction slightly (e.g., to 5%) makes UPower more robust and fault-tolerant, especially in edge cases like:

1. Battery age or wear,
2. Cold environments (which reduce available charge),
3. Unexpected spikes in CPU/GPU activity that cause battery drop near the end.

In effect, this makes UPower safer by design — it prevents machines from
entering an unrecoverable freeze state that forces users to hold the
power button to force a shutdown, which risks hardware and data.

Again, I understand that defaults must work across many hardware
scenarios, and I'm glad UPower is configurable. But I hope this helps
explain why I believe this change would improve the reliability of
Ubuntu systems by preventing critical-level system crashes, even if
rare.

Thanks again for your time and consideration.

** Attachment added: "H3FAhGPO.jpg"
   https://bugs.launchpad.net/ubuntu/+source/upower/+bug/2112342/+attachment/5881891/+files/H3FAhGPO.jpg

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https://bugs.launchpad.net/bugs/2112342

Title:
  UPower default PercentageAction=2.0 is too aggressive for degraded
  batteries — suggest changing to 5.0%

Status in upower package in Ubuntu:
  Incomplete

Bug description:
  Affected system:
  Laptop: Lenovo ThinkPad T490
  Ubuntu versions tested: Ubuntu 24.04 LTS and Ubuntu 25.04
  Battery condition: Moderate degradation (~36% capacity loss)

  upower:
    Installed: 1.90.7-1build1

  energy-full:         32.35 Wh
  energy-full-design:  50.5 Wh
  capacity:            64.06%

  On this system, when the battery level dropped to ~2%, the system
  attempted to perform a shutdown as configured by UPower default:

  PercentageAction=2.0

  However, due to the degraded state of the battery, the voltage dropped
  too rapidly at that level for the system to complete the shutdown
  properly. This resulted in a system freeze with a blinking Caps Lock
  LED, indicative of a kernel panic caused by power failure during a
  critical system operation.

  This issue occurred reliably and repeatedly on both Ubuntu 24.04 and
  25.04.

  Diagnosis:
  1. The battery has significantly reduced capacity (~64% of design).
  2. At 2% reported charge, there was insufficient residual energy to allow the shutdown process to complete.
  3. Increasing the threshold for the shutdown action to 5% resolved the issue completely.

  Solution:
  I edited the file /etc/UPower/UPower.conf and changed the following lines:

  PercentageLow=20.0
  PercentageCritical=10.0
  PercentageAction=5.0

  
  I also restarted the service:

  sudo systemctl restart upower

  
  After this change, the system reliably enters CriticalPowerAction when the battery reaches 5%, with no further freezes or panics.

  
  Suggested change to default UPower configuration:

  PercentageAction=5.0

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