Score:1

Quick Battery Drain in Suspend Mode

sa flag

I am using Ubuntu 22.10 and my laptop is a Dell XPS 13 9365. When I check my suspend type by typing

cat /sys/power/mem_sleep

it returns

s2idle [deep]

which I believe should save the most power. Despite this, I lose at least 4%-5% per hour. Recently my laptop battery was drained completely when initially fully charged in less than 12 hours.

David avatar
cn flag
You expected it to remain in suspend for over 12 hours? Does not seem reasonable. Did you check to see what the maker of the computer says about how long the battery should last in suspend.
Score:1
pl flag

sudo vi /sys/power/mem_sleep

Open the file with a super user account and edit and save:

s2idle [deep]

It should sleep in S3 sleep when you exexute systemctl suspend or equivalent to it.


Linux system has 4 sleep states

  • S0 - s2idle (freeze) Suspend-to-idle; providing power to SSD and RAM
  • S1 - shallow (stand-by) Power-on suspend; providing power lowest possible to CPU and I/O
  • S3 - deep Suspend-to-RAM; providing power to RAM, CPU goes off-line
  • S4 - disk Suspend-to-disk; write RAM information into Disk and give firmware control. Not many machines do this perfectly.

On XPS 13 93xx, might need to add "mem_sleep_default=deep" into boot option: This has been a confirmed bug (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1860390)

sudo vi /etc/default/grub

...
GRUB_CMDLINE_LINUX_DEFAULT="quiet mem_sleep_default=deep"
...

sudo update-grub


p.s. I am not sure that every machine can awake from S3 sleep perfectly.

Carter Hedinger avatar
sa flag
I typed that in and when it opened the file "[s2idle] deep" was already written there in the file. I noticed that executing "systemctl suspend" increases my battery life but it still loses around 2-3% per hour. Is that typical for deep sleep?
Sadaharu Wakisaka avatar
pl flag
@CarterHedinger, I am sorry that was my careless mistake, it meant to go in 's2idle' state. Now corrected and a little more information. Yes, 2-3% power drain in s2idle sounds normal to me. If you choose 'deep' S3 sleep then you get less energy drain, let's say s2idle for a day and deep for a couple days or a week. But I suggest to shutdown computer if you don't use for a week. Sleeping state on Linux OS is not designed in early days, I guess it still is not healthiest thing to do.
Score:0
cn flag

I had the same problem on Ubuntu 22.04, Dell Inspiron 15, where the deep suspend seem not to be supported by the manufacturer (and editing /sys/power/mem_sleep is not possible). Updating Linux kernel (e.g. following https://linuxhint.com/install-upgrade-latest-kernel-ubuntu-22-04/) made the battery drain much better in my case.

See also https://www.dell.com/community/XPS/XPS-13-9310-Ubuntu-deep-sleep-missing/m-p/8056343#M91204

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