The SMT function of the CPU was accidentally turned off in the cockpit

Rocky Linux Help & Support
1

The SMT function of the CPU was accidentally turned off in the cockpit. Is there any way to reopen it

This server is for home use. No security concerns need to be considered. Only its performance is required.

2

Does the cockpit have only one-way options?

I would guess that the “turn off” is via kernel command-line parameters. Check what you have in /etc/default/grub
(The GRUB bootloader does not read that file. The grub.cfg must be recreated if /etc/default/grub is modified.)

3

GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=“$(sed ‘s, release .*$,g’ /etc/system-release)”
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT=“console”
GRUB_CMDLINE_LINUX=“crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M rhgb quiet nosmt”
GRUB_DISABLE_RECOVERY=“true”
GRUB_ENABLE_BLSCFG=true

I can’t see which one

4

The option disabling SMT in there is nosmt

Try sudo grubby --update-kernel=ALL --remove-args='nosmt', which should remove it and automatically update the grub configuration.

1 Like
5

thank you. SMT is finally re enabled.

I always use echo on>/sys/devices/system/cpu/smt/control to enable it. But every time you restart the system, SMT will always shut down again. Now it is finally normal.