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Script to manage swap on:

• zswap - Enable/Configure
• zram - Autoconfigurating for swap
• files - (sparse files for saving space, supports btrfs)
• block devices - auto find and do swapon

ℹ️ It is configurable in/etc/systemd/swap.conf.

Additional terms:

• SwapFC (File Chunked) - provides a dynamic swap file allocation/deallocation

/etc/systemd/swap.conf/usr/lib/systemd/system/systemd-swap.service/usr/bin/systemd-swap

sudo systemctlenable --now systemd-swap

• Arch Linux: in thecommunity repo.

• Debian based distros

  git clone https://github.com/Nefelim4ag/systemd-swap.gitcd systemd-swapmake debsudo apt install ./systemd-swap_*_all.deb

• Fedora based distros

  sudo dnf coprenable zeno/systemd-swapsudo dnf install systemd-swap

  or

  git clone https://github.com/Nefelim4ag/systemd-swap.gitcd systemd-swapmake rpmsudo dnf install ./systemd-swap-*noarch.rpm

• Manual

  Install dependencies:

  • python3 >= 3.7
  • python3 packages:systemd-python andsysv_ipc

  git clone https://github.com/Nefelim4ag/systemd-swap.gitcd systemd-swapsudo make install# or into /usr/local:sudo make prefix=/usr/local install

Q: Do we need to activate both zram and zswap?
A: Nope, it's useless, as zram is a compressed RAM DISK, but zswap is a compressed"writeback" CACHE on swap file/disk. Also having both activated can lead to inverse LRU as notedhere

Q: Do I need to useswapfc_force_use_loop on swapFC?
A: Nope, as you wish really, native swapfile should work faster and it's safer in OOM condition in comparison to loop backed scenario.

Q: When would we want a certain configuration?
A: In most cases zram is enough since it on average compresses 2-3x and is much faster than disk based swap.

Q: How many zram devices should one use?A: If you are not using an ancient kernel (pre 4.7) there's no benefit from using multiple zram devices.

Q: Can we use this to enable hibernation?
A: Nope as hibernation wants a persistent fs blocks and wants access to swap data directly from disk, this will not work on:swapfc (without some magic of course, see#85).

• Enable swapfc if wanted (note, you shouldnever use zram and zswap at the same time)

  vim /etc/systemd/swap.conf.d/overrides.conf

  swapfc_enabled=1

• Stop any external swap:

  sudo swapoff -a

• Remove swap entry from fstab:

  vim /etc/fstab

• Remove your swap

  # For Ubuntusudo rm -f /swapfile# For Centos 7 (if using a swap partition and lvm)lvremove -Ay /dev/centos/swaplvextend -l +100%FREE centos/root

• Remove swap from Grub:

  # For Ubuntu remove resume* in grubvim /etc/default/grub# For Centos 7 remove rd.lvm.lv=centos/swap*vim /etc/default/grub# For Manjaro remove resume* in grub & mkinitcpiovim /etc/default/grubvim /etc/mkinitcpio.conf

  # For Ubuntuupdate-grub# For Centos 7grub2-mkconfig -o /boot/grub2/grub.cfg# For Manjaroupdate-grubmkinitcpio -P