No swap in FSTAB after update to 24.04

I was rendering a project in Blender when I noticed I was getting low on memory. I expected to see it start to use the swap partition, but then it crashed. Confused, I did “swapon -s” and nothing was listed. I then checked the FSTAB and … yep… no swap entry.

Its been a long time since I had to manually add a swap entry to the FSTAB and I have completely forgotten how to identify its UUID number, as I do not like using /dev/sdX due to hot plugging issues often renaming things.

So my questions are, how do I get the swap partitions UUID, and then, are the standard switches in the FSTAB ok, or is there something specific to Neon I should be aware of?

(and should I file a bug report? Where, and what would I call it?)

You can run, in a konsole,

sudo blkid

Or, use the KDE Partition Manager, right-click the swap partition and Properties.

For human-maintained fstab entries, IMO labels are less error-prone; this system’s swap entry is

LABEL=swan   none             swap   sw                   0   0

The KDE Partition Manager can set the label.

These days swap files are often created by default. The fstab entry has just the path to the file.

I’m not a Neon user so I’m not sure on what would have caused that, but theoretically nothing on the “upper layer” of the OS like KDE Plasma/Frameworks/Gear should cause fundamentally different operation for super low-level things like fstab.

I see there’s already a post mentioning you can use sudo blkid, just as a heads up, you can also get the UUID for a partition through lsblk --fs without needing to use sudo.

I’m not sure that it’s worth having a swap partition - I’d just delete that and set up swap file… especially if using SSD it’s just a better and slicker option.

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This was after the 22.04 to 24.04 rebase, in which I imagine the installer must have borked the FSTAB in the same way it borked the EFI partition lables. This seems likely a Calimaras (sp?) issue. I should check the kubuntu FSTAB see if it got borked after the 24.10 update. That may explain the crashes in Blender there too now that I think about it. Maybe an Ubuntu issue, not Neon.

I hear you. This install is years old, and me being a dinosaur, I just built the partitions the way I have always built them. I had already added a swap file as a secondary swap area. Both were gone from the FSTAB. I think I am going to grow the swap file and then delete the partition and give it back to the system partition.

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Thank you. I think I got it. We will find out after a reboot I guess. :wink: Wish me luck!