Intel_pstate...

[ethon]

How do I implement:

intel_pstate=disable

permanently into my startup? I know I can do it each time I boot, but I need to make it permanent or the machine won't boot.

Step by step please, I'm very new to this part of unix.

Ethon

[TrevorH]

Edit /etc/default/grub and add it to the kernel parameters in that file. That should take effect on all new kernels installed once that file is edited. To have it take effect on the current one you will need to edit /boot/grub2/grub.cfg and add it there too.

[ethon]

Edit /etc/default/grub and add it to the kernel parameters in that file. That should take effect on all new kernels installed once that file is edited. To have it take effect on the current one you will need to edit /boot/grub2/grub.cfg and add it there too.

There is no grub.cfg file in my /boot/grub2 directory. Do I need to create it? Also, the contents of the grub file don't look anything like what I see when I edit it from startup. Should they be the same?

[TrevorH]

The /etc/default/grub file is used to construct the actual file from parts. You want to add to the GRUB_CMDLINE_LINUX= bit, inside the quotes.

If you're on a UEFI system then the config file is in a different location - I think something like /boot/EFI/efi/grub.cfg, you might need to hunt around under /boot/EFI for it since I'm not sure exactly where it is.

[ethon]

The /etc/default/grub file is used to construct the actual file from parts. You want to add to the GRUB_CMDLINE_LINUX= bit, inside the quotes.

If you're on a UEFI system then the config file is in a different location - I think something like /boot/EFI/efi/grub.cfg, you might need to hunt around under /boot/EFI for it since I'm not sure exactly where it is.

The only file I have been able to find and modify is the etc/default/grub file. I can find no other files that you have mentioned in any location.

BTW, making the change to the grub file did not change the boot, so it must not be reading that particular file. Any more details about where this might be?

[TrevorH]

The /etc/default/grub file only affects future kernel installs or the output from the grub2-mkconfig command. You could run that too but you would still need to know where the actual file it is using resides since you have to point that command at it so it can overwrite it. I don't have a UEFI system (well I do but I disable that stuff whenever I can). Post the output from ls -laR /boot/EFI/ and perhaps we can find it or someone who knows about UEFI systems can suggest the correct location.

[ethon]

The /etc/default/grub file only affects future kernel installs or the output from the grub2-mkconfig command. You could run that too but you would still need to know where the actual file it is using resides since you have to point that command at it so it can overwrite it. I don't have a UEFI system (well I do but I disable that stuff whenever I can). Post the output from ls -laR /boot/EFI/ and perhaps we can find it or someone who knows about UEFI systems can suggest the correct location.

Here is the listing, although I've looked through all of these and didn't see what you were referring to:

/boot/efi/:
total 24
drwx------. 3 root root 16384 Dec 31 1969 .
dr-xr-xr-x. 5 root root 4096 Dec 13 18:16 ..
drwx------. 4 root root 4096 Dec 13 21:32 EFI

/boot/efi/EFI:
total 28
drwx------. 4 root root 4096 Dec 13 21:32 .
drwx------. 3 root root 16384 Dec 31 1969 ..
drwx------. 2 root root 4096 Dec 13 21:32 BOOT
drwx------. 3 root root 4096 Dec 13 18:14 centos

/boot/efi/EFI/BOOT:
total 1428
drwx------. 2 root root 4096 Dec 13 21:32 .
drwx------. 4 root root 4096 Dec 13 21:32 ..
-rwx------. 1 root root 1384792 Jul 2 09:02 BOOTX64.EFI
-rwx------. 1 root root 64776 Jul 2 09:02 fallback.efi

/boot/efi/EFI/centos:
total 5836
drwx------. 3 root root 4096 Dec 13 18:14 .
drwx------. 4 root root 4096 Dec 13 21:32 ..
-rwx------. 1 root root 128 Jul 2 09:02 BOOT.CSV
drwx------. 2 root root 4096 Dec 13 21:31 fonts
-rwx------. 1 root root 954752 Jun 30 17:16 gcdx64.efi
-rwx------. 1 root root 5139 Dec 13 18:14 grub.cfg
-rwx------. 1 root root 954752 Jun 30 17:16 grubx64.efi
-rwx------. 1 root root 1268168 Jul 2 09:02 MokManager.efi
-rwx------. 1 root root 1384792 Jul 2 09:02 shim.efi
-rwx------. 1 root root 1376112 Jul 2 09:02 shim-redhat.efi

/boot/efi/EFI/centos/fonts:
total 2512
drwx------. 2 root root 4096 Dec 13 21:31 .
drwx------. 3 root root 4096 Dec 13 18:14 ..
-rwx------. 1 root root 2560080 Jun 30 17:16 unicode.pf2

[ethon]

Okay, I think I might be starting to understand how this works. So basically, you set the parameters you want in a config file, then use something else that actually picks up those parameters and builds the actual grub file.

I see the grub.cfg file under the EFI, and I can see the parameters I am seeing on boot. I am presuming this is what you were saying to edit, but with all the dire warnings at the beginning of the file indicating I shouldn't directly edit this file, it sounds like the "correct" way to do this is to make the file.

Sorry for being such a newbie.

[TrevorH]

You want /boot/efi/EFI/centos/grub.cfg and, yes, it has dire warnings in it but that's because it gets created when a new kernel is installed or an old one removed and if you don't also edit /etc/default/grub then your changes will be lost. I can't vouch for UEFI systems but on normal ones it's perfectly possible to edit the file itself as long as you don't make any syntax errors.

[MoonWolf]

Or you may use grub2-mkconfig.