Hi there!
First of all, I just wanted to say how super happy I am about having lowlatency built-in to the Generic kernel and that we are going to be removing the lowlatency kernel from future kernel releases. However, this does cause some questions and leaves Ubuntu Studio in a state of ambiguity when it comes to the kernel.
I do wish the kernel team would have told me that the lowlatency kernel was planned to be sunset prior to 24.04’s release so that we could have planned accordingly, especially considering the HWE stack. Speaking of which, and I’m assuming here that the HWE kernels will not have a lowlatency variant since they’re, for all intents and purposes, backports of what lands in later Ubuntu releases. Is this going to be the case?
Right now, the plan, due to the HWE stack and assuming there is no lowlatency kernel going forward, is to reconfigure livecd-rootfs so that our Noble images so that they use the generic kernel for 24.04.1 and forward, and to reconfigure our ubuntustudio-lowlatency-settings package so that our default kernel parameters not only include threadirqs but also preempt=full and nohz_full=all which is rather trivial.
So, please let me know, and I hope to have better communication with the kernel team in the future. 
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Hi @eeickmeyer, we (kernel team) are sill planning to support lowlatency for 24.04, same with the backported HWE kernels based on 24.04 that will have a lowlatency variant. Did you see any comment / message that is stating the opposite or am I missing something? Thanks for pointing this out.
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Hi @arighi ,
This came from a post by @brettgrand on Linkedin:
Now that in 24.04 all linux-lowlatency configuration options have migrated to settings or merged with linux-generic, there is no need for a distinct linux-lowlatency binary any more and eventually will be deprecated.
It would make sense that the lowlatency kernel would be deprecated with this, but now it seems as though there’s a conflict in messaging because now I’m really confused.
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The LinkedIn post does sound confusing. The key takeaway for me is “eventually”. I can imagine that’s something on the roadmap towards 24.10 (or later), and doesn’t (yet) affect 24.04.X. Like you, I hope this roadmap will be communicated in timely fashion.
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@eeickmeyer that post was worded a bit vaguely. it should have read ‘and eventually will be deprecated in a future release of Ubuntu’. we would never make such a drastic change in a released stable kernel. this was just the initial notice that there is no reason to maintain 2 distinct binaries any more and we will eventually, in some future release of Ubuntu, do something to consolidate, but how and when is yet TBD
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Thanks for the response, @brettgrand .
My concern is that, as I understand it, the HWE kernels are usually a 1:1 backport of the kernel from the later release, for instance 24.10’s kernel would be the HWE-a kernel, 25.04’s kernel would be the HWE-b kernel, and so on.
With that in mind, it would validate my concern that one of those later kernels would not have the lowlatency binary built. That said, I might not know the picture here or the complete engineering behind how or what is being done here.
While I do understand that the 6.8 lowlatency kernel will not disappear, one of the later HWE kernels, which would be the default for a later point release update, could potentially not have the lowlatency kernel, in which case a SRU to both livecd-rootfs and ubuntustudio-lowlatency-settings would be needed.
Ubuntu Studio is committed to a 3-year LTS period with support ending in April 2027. While I understand these kernel support concerns are TBD, I would like to keep these communication channels open so that if and when something is decided, I can know as soon as possible.
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