Battery Capacity Diminished After Jaunty Upgrade

Bug #354584 reported by Joe Barnett
10
Affects Status Importance Assigned to Milestone
linux (Ubuntu)
Invalid
Undecided
Unassigned

Bug Description

very possibly just a coincidence of timing, but after upgrading to Jaunty lat week, my laptop's battery life has severely diminished. Used to get ~2 hours on battery, but now down to 10-20 minutes (usually operate docked & plugged in, so unfortunately don't know if the battery life was this bad immediately before jaunty upgrade). On login, gnome-power-manager gives me a warning that battery is old or broken, w/ capacity of only 49%.

also, for what it's worth:

$ cat /proc/acpi/battery/BAT0/info
present: yes
design capacity: 5200 mAh
last full capacity: 2574 mAh
battery technology: rechargeable
design voltage: 11100 mV
design capacity warning: 520 mAh
design capacity low: 157 mAh
capacity granularity 1: 52 mAh
capacity granularity 2: 52 mAh
model number: DELL XD7366
serial number: 1890
battery type: LION
OEM info: SMP

again, probably just end of battery's lifetime, but is it possible that some sort of power management change could have caused this ?

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 9.04
MachineType: Dell Inc. Latitude D820
NonfreeKernelModules: nvidia
Package: linux-image-2.6.28-11-generic 2.6.28-11.39
ProcCmdLine: root=UUID=dec075cc-fdda-447f-b8c5-67b244f5f126 ro quiet splash
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.28-11.39-generic
SourcePackage: linux

Revision history for this message
Joe Barnett (thejoe) wrote :
Revision history for this message
Leann Ogasawara (leannogasawara) wrote :

Hi Joe,

Just curious if you boot into an older Intrepid 2.6.27 kernel does the battery capacity return to it's typical expected ~2hr battery life? It might help determine if it's really the battery going bad or a kernel regression. Please let us know. Thanks.

Changed in linux (Ubuntu):
status: New → Incomplete
Revision history for this message
Augusto Santos (mkhaos7) wrote :

I'm experiecing a similar behavior.
When I had intrepid my battery lasted, at least, 3 to four hours (Dell Vostro 1000, 9 cell battery), with Jaunty I'm experiencing the same 10-20 minutos battery life as Joe.

I've tried running powertop and using it recomendations but that didn't seen to help.
Dunno if this is relavant, but it says that it cannot get a estimated baterry live from ACPI.

I'll try loading a 2.6.27 or a 2.6.29 kernel to see what it gives me.

Any aditional info I'll be glad to provide!

Revision history for this message
Augusto Santos (mkhaos7) wrote :

Ok.
A feedback some time latter... for me it was just a coincidence between my battery dying and the installation of Jaunty :)
I changed my battery and everything was ubber. So, no issue in this area for me...

Revision history for this message
JMiykal (jmiykal) wrote :

I have noticed the same problem as mentioned above (Joe's original post). When I boot up, my battery shows itself nearly full, or around 85% or whatever... then, very suddenly, it either gives me an almost-dead warning, or just plain shuts down. It doesn't appear that power is being consumed faster than before, but as if some specific action of Jaunty is suddenly sapping the power.

Since this is a fairly fresh Jaunty install, pretty sure I don't have any older kernels to roll back to, but here's the contents of my info file:

present: yes
design capacity: 4000 mAh
last full capacity: 4000 mAh
battery technology: rechargeable
design voltage: 14800 mV
design capacity warning: 420 mAh
design capacity low: 156 mAh
capacity granularity 1: 264 mAh
capacity granularity 2: 3780 mAh
model number: PA3383U
serial number: 3658Q
battery type: Li-Ion
OEM info: TOSHIBA

This is too odd to be a coincidence; I just upgraded to Jaunty last week, and I frequently used the laptop unplugged, so I know it's not a fluke.

Revision history for this message
JMiykal (jmiykal) wrote :

After posting above comment, acpi -t returned "Battery 0: Charging, 22%, charging at zero rate - will never fully charge." Was up to 23% a few min later. I restarted my laptop. Tray applet and acpi showed it at 100% charge, but of course said that was an estimate. Leaving it plugged in all day to (hopefully) charge it completely, will see what happens when I get home.

Revision history for this message
JMiykal (jmiykal) wrote :

Just arrived home. Unplugged laptop and booted. acpi -t says at 99%, discharging at 0 rate, "will never discharge". About a minute later, down to 96%. Dropping about 2-3% per minute, for the time being, but keeps saying "discharging at zero rate, will never fully discharge". Something's not right with that power monitor.

Joe Barnett (thejoe)
Changed in linux (Ubuntu):
status: Incomplete → Invalid
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