How to set up the power management for Dell XPS 13

Use the Dell OEM Ubuntu ios file to install the ubuntu 18.04LTE.*

systemd sleep:

You can use pm-utils to manage the system for suspend/sleep/hibernate, see the doc in archlinux for details.

Ubuntu uses systemd to manage suspend/sleep/hibernate. If cat /sys/power/mem_sleep return

[s2idle] deep

This confirms that the default suspend mode is s2idle (since it is highlighted with brackets).

To permanently fix sleep to deep, you should sudo -H gedit /etc/default/grub. Replace the line

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

with

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash mem_sleep_default=deep"

Regenerate your grub configuration by run sudo update-grub.

Now the XPS is able to hibernate… Keep reading the new updates.

Another way to hibernate is to use the s2disk from uswsusp. See more details in this link: https://askubuntu.com/a/1132154

Newly update on 25/12/2019

After several update of the Ubuntu 18.04 system (18.04.3 LTS now), I tried sudo systemctl hibernate which works now. Then I can do the suspend-then-hibernate with a few steps.

If you have a problem of Failed to hibernate system via logind: Sleep verb not supported, try to disable fastboot in the BIOS and do not use UEFI for disk. You will also need to increase the swapfile size larger than your laptop memory with these steps:

Turn off all swap processes
```
sudo swapoff -a
```

Resize the swap

sudo dd if=/dev/zero of=/swapfile bs=1G count=8

if = input file of = output file bs = block size count = multiplier of blocks

Make the file usable as swap
```
sudo mkswap /swapfile
```
Activate the swap file
```
sudo swapon /swapfile
```
Check the amount of swap available
```
grep SwapTotal /proc/meminfo 
```

Try to modify the /etc/default/grub file

GRUB_CMDLINE_LINUX_DEFAULT="no_console_suspend initcall_debug resume=/dev/where_your_swap_file_is resume_offset=xxxx"

The xxxx should be replaced by the first number under physical_offset in the output of sudo filefrag -v /swapfile

$ sudo filefrag -v /swapfile
Filesystem type is: ef53
File size of /swapfile is 17179836416 (4194296 blocks of 4096 bytes)
 ext:     logical_offset:        physical_offset: length:   expected: flags:
0:        0..    2048:   59082751..  59084799:   2049:            
1:     2049..   28671:   59086848..  59113470:  26623:   59084800:
...

xxxx = 59082751

Update your grub file with sudo update-grub
Try to hibernate your laptop with
```
sudo systemctl hibernate
```
If this works fine, you can change the /etc/default/grub file back to
```
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash resume=/dev/where_your_swap_file_is resume_offset=xxxx"
```
Otherwise, you will get more information on why the hibernate fails. Don’t forget sudo update-grub to make the changes take effect.

Now, we make the laptop first deep-sleep then hibernate.

First create a file in /etc/systemd/sleep.conf

sudo vi /etc/systemd/sleep.conf

Add these content

[Sleep]
HibernateDelaySec=3600

test it by command:

sudo systemctl suspend-then-hibernate

you can edit HibernateDelaySec to reduce delay to hibernate.

If all works fine you can change Lid Close Action by editing the file /etc/systemd/logind.conf. You need to find option HandleLidSwitch=, uncomment it and change to HandleLidSwitch=suspend-then-hibernate. Then you need to restart systemd-logind service (warning! you user session will be restarted) by the next command:

sudo systemctl restart systemd-logind.service

That should work all fine.

Install tlp and/or powertop to save your buttery cost.

TLP usage: https://linrunner.de/en/tlp/docs/tlp-linux-advanced-power-management.html

powertop usage: https://www.tecmint.com/powertop-monitors-linux-laptop-battery-usage/

To avoid the wifi random dropping problem:

Try disabling wifi power management by opening ``/etc/NetworkManager/conf.d/default-wifi-powersave-on.conf` and changing

wifi.powersave = 3

wifi.powersave = 2

Do not set it to 0, which is the default value. From nm-setting-wireless.h:

/**
 * NMSettingWirelessPowersave:
 * @NM_SETTING_WIRELESS_POWERSAVE_DEFAULT: use the default value
 * @NM_SETTING_WIRELESS_POWERSAVE_IGNORE: don't touch existing setting
 * @NM_SETTING_WIRELESS_POWERSAVE_DISABLE: disable powersave
 * @NM_SETTING_WIRELESS_POWERSAVE_ENABLE: enable powersave
 *
 * These flags indicate whether wireless powersave must be enabled.
 **/
 
typedef enum {
    NM_SETTING_WIRELESS_POWERSAVE_DEFAULT       = 0,
    NM_SETTING_WIRELESS_POWERSAVE_IGNORE        = 1,
    NM_SETTING_WIRELESS_POWERSAVE_DISABLE       = 2,
    NM_SETTING_WIRELESS_POWERSAVE_ENABLE        = 3,
    _NM_SETTING_WIRELESS_POWERSAVE_NUM, /*< skip >*/
    NM_SETTING_WIRELESS_POWERSAVE_LAST          =  _NM_SETTING_WIRELESS_POWERSAVE_NUM - 1, /*< skip >*/
} NMSettingWirelessPowersave;

Original post 2019-03-10, updated 2019-07-15, updated again in 2019-09-19