[SOLVED] How can I force swappiness=0

As far as I know swappiness=0 isn't supported anymore. If you don't want swapping at all, why don't you just remove your swap partition (open /etc/fstab and comment out the line that mounts your swap partition)? If you don't want to reboot you can also run swapoff -a to temporarily disable swapping.
 
To make it persistent you need to add the following line to /etc/sysctl.conf :
vm.swappiness=0
 
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From the kernel documentation:
This control is used to define the rough relative IO cost of swapping and filesystem paging, as a value between 0 and 200. At 100, the VM assumes equal IO cost and will thus apply memory pressure to the page cache and swap-backed pages equally; lower values signify more expensive swap IO, higher values indicates cheaper.
...
At 0, the kernel will not initiate swap until the amount of free and file-backed pages is less than the high watermark in a zone.
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So "swappiness=0" won't disable swap, it will just swap out very late. If you want the OOM to kill processes instead of swapping out RAM you really need to disable swap by swapoff -a or unmounting the swap device/file.
 
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Emilien said:
I didn't get the motivation to disable swap...
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A case could be creating a Kubernetes node.

If anyone else ends up here looking to disable swap to create a Kubernetes node template...

Dunuin said:
As far as I know swappiness=0 isn't supported anymore. If you don't want swapping at all, why don't you just remove your swap partition (open /etc/fstab and comment out the line that mounts your swap partition)? If you don't want to reboot you can also run swapoff -a to temporarily disable swapping.
Click to expand...

As Dunuin comments ^, the commenting out of the swap partition line in /etc/fstab seems to also be necessary.
 
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KSpur said:
A case could be creating a Kubernetes node.

If anyone else ends up here looking to disable swap to create a Kubernetes node template...



As Dunuin comments ^, the commenting out of the swap partition line in /etc/fstab seems to also be necessary.
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Doesn't kubernetes support swap now?
 
Quick follow up question to all this, after disabling swap, do I need to re-configure any of my lxcs swap settings? Or is it OK to just leave them thinking they have swap?
 
johnsturgeon said:
Quick follow up question to all this, after disabling swap, do I need to re-configure any of my lxcs swap settings? Or is it OK to just leave them thinking they have swap?
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Have you checked if they see the 0 swap? If they see it, the settings swap cannot be used.

Why do you want to disable swap?
 
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