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Stop making swap partitions
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swap.md

Stop making swap partitions—use swap files instead!

Swap files have had the same performance characteristics as swap partitions for almost 20 years[1] and yet, linux distributions continue to encourage the use of swap partitions during install.

Swap files are easier to use/add/remove/modify/extend after installation. They're better in every way––use swap files!

  1. Create a swap file.

💡 You can use dd for this too but if your filesystem supports it, fallocate is faster.

fallocate -l 4G /swapfile
  1. Only root should be able to write to the swap file.
chmod 0600 /swapfile
  1. Format the swap file.
mkswap /swapfile
  1. Enable it.
swapon /swapfile
  1. Make it persist across boots.
echo "/swapfile none swap defaults 0 0" >> /etc/fstab

[1] https://lkml.org/lkml/2005/7/7/326

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joshenders commented Dec 7, 2023 •
edited

If you're using btrfs:

btrfs filesystem mkswapfile --size 2G swapfile
swapon swapfile

https://btrfs.readthedocs.io/en/latest/Swapfile.html

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