Disable SMT / Hyper Threading on Grub:

This will disable SMT (called Hyper-threading on intel systems) for Linux through a grub option:

edit the /etc/default/grub file and add:

nosmt=force
to the GRUB_CMDLINE_LINUX_DEFAULT= line.

Save the file and reboot the computer and now SMT is disabled.

Sources: baeldung, Server Fault.
Date in Vivaldi: September 23rd 2023.

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