[20:08] <sem> Hey everyone. I installed "ubuntustudio" initially on my laptop but I am trying to make it boot into the normal kernel instead of lowlatency for the power saving features.
[20:09] <sem> I noticed that update-grub pulls in /etc/default/grub.d/ubuntustudio.cfg which always sets the default boot option to lowlatency
[20:10] <sem> what is the "ubuntu studio" preferred method to specify that you want to boot the normal kernel by default? Can I just comment out this line in ubuntustudio.cfg or will this be overwritten in updates (and is it still the best idea) or is there a better way
[20:18] <Eickmeyer> sem: You can if you want. Up to you.
[20:20] <Eickmeyer> sem: If you edit that config, updates will not overwrite it, but upgrading to 24.04 will likely overwrite it, though it might ask you first.
[20:21] <sem> Alright, I think I will put in a comment explaining what I edited and why so when I upgrade, showing the files side by side will explain things
[20:21] <Eickmeyer> sem: That said, you don't have to worry about that until April or so.
[20:22] <sem> just to sanity check, the -generic kernel is the one which will have slightly better power management? I don't need -amd64 or something
[20:22] <Eickmeyer> You'll get amd64 by default. The package you want is linux-generic.
[20:22] <Eickmeyer> amd64 is likely your architecture.
[20:23] <Eickmeyer> !info linux-generic mantic
[20:23] <sem> when I do 'uname -r' it shows 6.5.0-13-generic ...?
[20:23] <Eickmeyer> That means you booted the generic kernel.
[20:24] <sem> But I actually should have booted -amd64 for the correct performance stuff?
[20:24] <sem> or is it correct to boot the generic kernel
[20:25] <Eickmeyer> No. amd64 is just the architecture, not a kernel flavor.
[20:25] <sem> oh ok. I have an old memory of booting the -i386 kernel or the -amd64 kernel; i think that used to be a thing maybe
[20:26] <Eickmeyer> If you want the generic by default, all you have to do is edit /etc/default/grub.d/ubuntustudio.cfg and replace "lowlatency" in line 4 to read "generic".
[20:27] <sem> so if 'threadirqs' is still added to the commandline that's ok?
[20:27] <Eickmeyer> Depends. Are you trying to avoid xruns at all?
[20:29] <sem> Ideally I would boot into the lowlatency kernel and avoid xruns when doing audio work (and choose that from the grub menu) but by default, boot into a kernel that optimizes for battery life / performance.
[20:30] <Eickmeyer> Unfortunately, there's no easy way to do that by just switching kernels. Threadirqs does take a power hit, but it is essential to avoiding xruns and activating the lowlatency effects of both the generic and lowlatency kernel. Without it, the lowlatency kernel isn't as lowlatency as it can be and *will* have xruns.
[20:30] <Eickmeyer> With that, you'll have to make compromises.
[20:32] <sem> My understanding might be a little confused... can I save the boot entry for "lowlatency" to add "threadirqs", but the boot entry for -generic doesn't have it? (Similar to having one boot entry with "quiet splash" and another one without it)
[20:32] <Eickmeyer> Another way is to use the refind bootloader, which is in the repositories. After it's installed, you can use "sudo dpkg-reconfigure ubuntustudio-lowlatency-settings" which will then configure between using threadirqs for lowlatency and not for generic as its postinstall script is refind-aware.
[20:33] <Eickmeyer> !info refind mantic
[20:33] <Eickmeyer> sem: Sadly, for grub, it doesn't work that way. It's either all or nothing.
[20:33] <sem> Ok. Maybe it is time I learned to use a new bootloader :)
[20:34] <Eickmeyer> sem: We used to have it for grub that it automatically put threadirqs only for lowlatency, but the script that did that became incompatible with this version of grub in 23.10, so we were forced to drop it. It was so incompatible our .iso images failed to build.
[20:35] <sem> the other thing I don't like about grub is that its OS_Prober does weird things to overwrite your /etc/default/grub configurations, so I have to always disable OS_Prober
[20:36] <Eickmeyer> sem: You can read more about refind here: http://www.rodsbooks.com/refind/
[20:42] <sem> according to the website it is a bootmanager not a bootloader, but the kernel is able to bootload itself; that is good to know
[20:43] <Eickmeyer> sem: Exactly. I use it and prefer it.