Systemd-swap Error

Hello experts,

I was trying to enable systemd-swap,
i used following commands,

sudo pacman -S systemd-swap
sudo systemctl enable systemd-swap.service

and

sudo bash -c 'echo -e "zswap_enabled=1\nzram_enabled=0\nswapfc_enabled=1" > /etc/systemd/swap.conf.d/myswap.conf'

and on using this last command i am getting the below error

Please help in resolving the issue…thanks

Manually create the file /etc/systemd/swap.conf.d/myswap.conf like so… :arrow_down:

sudo nano /etc/systemd/swap.conf.d/myswap.conf

Add the lines… :arrow_down:

zswap_enabled=1
zram_enabled=0
swapfc_enabled=1

… to the file, followed by a newline (i.e. an empty line).

Save the file with Ctrl+O followed by Enter, and exit the editor with Ctrl+X. :wink:

Hello,
I recommend zram-generator instead.

1 Like

even I am getting error using your method

Do you actually have a directory /etc/systemd/swap.conf.d? If not, you have to create it first. :arrow_down:

sudo mkdir /etc/systemd/swap.conf.d

Then create the file.

i executed this command and it worked.
after this i created the file…

but after reboot, it is not showing any swap…

even in htop it is not showing any swap

Output of systemctl status systemd-swap.service?

here is the output…

[sonal@sonal-80e5 ~]$ systemctl status systemd-swap.service
● systemd-swap.service - Manage swap spaces on zram, files and partitions.
     Loaded: loaded (/usr/lib/systemd/system/systemd-swap.service; enabled; vendor preset: disabled)
     Active: active (running) since Sat 2021-05-22 23:34:17 IST; 8min ago
   Main PID: 563 (systemd-swap)
     Status: "Monitoring memory status..."
      Tasks: 1 (limit: 9423)
     Memory: 16.6M
     CGroup: /system.slice/systemd-swap.service
             └─563 /usr/bin/python3 -u /usr/bin/systemd-swap start

May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Zswap: backup current configuration: start
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Zswap: backup current configuration: complete
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Zswap: set new parameters: start
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Zswap: Enable: 1, Comp: zstd, Max pool %: 25, Zpool: z3fold
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Zswap: set new parameters: complete
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: Writing destroy info...
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: swapD: pick up devices from systemd-gpt-auto-generator
May 22 23:34:07 sonal-80e5 systemd-swap[563]: INFO: swapD: searching swap devices
May 22 23:34:17 sonal-80e5 systemd-swap[563]: INFO: swapFC: on-demand swap activation at >5116 MiB memory usage
May 22 23:34:17 sonal-80e5 systemd[1]: Started Manage swap spaces on zram, files and partitions..
[sonal@sonal-80e5 ~]$

Hi, avoid zram (that bloats ram and conficts with zswap)

Try this (translaton about ok :wink: )

1 Like

but i just enabled zswap…i dont know if i am using zram or not…
how did you concluded that i am using zram…

I think it’s not showing because it isn’t actually swapping. It is using part of your RAM as swap instead. :thinking:

2 Likes

yes sir , you are correct…when i opened multiple app to fill up the RAM it started showing the swap…

Thank you for the help

1 Like

maybe this?

I didn’t, it’s just advice.
what are the answers of

cat /etc/systemd/swap.conf
ls /etc/systemd/swap.conf.d -1

here…

[sonal@sonal-80e5 ~]$ cat /etc/systemd/swap.conf
#  This file is part of systemd-swap.
#
# Entries in this file show the systemd-swap defaults as
# specified in /usr/share/systemd-swap/swap-default.conf
# You can change settings by editing this file.
# Defaults can be restored by simply deleting this file.
#
# See swap.conf(5) and /usr/share/systemd-swap/swap-default.conf for details.

#zswap_enabled=1
#zswap_compressor=zstd
#zswap_max_pool_percent=25
#zswap_zpool=z3fold
#zram_enabled=0
#zram_size=$(( RAM_SIZE / 4 ))
#zram_count=${NCPU}
#zram_streams=${NCPU}
#zram_alg=zstd
#zram_prio=32767
#swapfc_enabled=0
#swapfc_force_use_loop=0
#swapfc_frequency=1
#swapfc_chunk_size=256M
#swapfc_max_count=32
#swapfc_min_count=0
#swapfc_free_ram_perc=35
#swapfc_free_swap_perc=15
#swapfc_remove_free_swap_perc=55
#swapfc_priority=50
#swapfc_path=/var/lib/systemd-swap/swapfc/
#swapfc_nocow=1
#swapfc_directio=1
#swapfc_force_preallocated=0
#swapd_auto_swapon=1
#swapd_prio=1024

here

[sonal@sonal-80e5 ~]$ ls /etc/systemd/swap.conf.d -1
myswap.conf

Ohh …anyways I followed your tutorial and everything is working fine now…i guess :slight_smile:

1 Like

Happy if it helped U ! :slight_smile:
Now just for check:

cat /etc/systemd/swap.conf.d/myswap.conf
cat /etc/systemd/swap.conf.d/overrides.conf

Screenshot_20210527_181701

Hi, nice, I think the two first lines may be redundant.

Check with:

cat /usr/share/systemd-swap/swap-default.conf

What do you think @Aragorn ?

I have no idea ─ I don’t use systemd-swapd, nor zram, nor zswap. :stuck_out_tongue:

Either way, the OP has indicated that “everything is working fine”, so I guess the matter is resolved. :man_shrugging:

1 Like

Then, the point I raised must be checked : never good to have redundant instructions as they can ultimately conflict. :wink:

1 Like