Comment 118 for bug 1842320

My XPS 13 9380 (no luks) also triggers this on 5.19 after the 22.10 upgrade; I can see the initrd is about 7% bigger in 22.10 over 22.04.

 -rw-r--r-- 1 root root 111203941 Oct 30 18:16 initrd.img-5.15.0-52-generic
 -rw-r--r-- 1 root root 120222346 Oct 31 21:39 initrd.img-5.19.0-23-generic

#103 lays out some interesting blockers for grub2, so as of right now there is no simple way to get upstream through ubuntu repositories as grub2 2.06-2ubuntu12 does not have a fix.

I think it is interesting that in https://lists.gnu.org/archive/html/grub-devel/2017-03/msg00037.html there was pushback on autodetection to fix this, citing "that machine that nobody heard of that will fail" however it ended up being a bunch of not-yet-built systems that failed

Looking at initramfs-tools in Jammy, the very last changelog entry was the change to lower compression, that is triggering this issue:

 http://changelogs.ubuntu.com/changelogs/pool/main/i/initramfs-tools/initramfs-tools_0.140ubuntu13/changelog

 initramfs-tools (0.140ubuntu13) jammy; urgency=medium

  * Lower the compression levels for zstd and lz4 (LP: #1958148)
    Following the discussion on the mailing list, we have reached
    a conclusion to lower the default compression levels:
    - For lz4, the compression level is lowered to 2 from 9
    - For zstd, the compression level is lowered to 1 from 19

Simple fix IMHO is to just go back one version. Ubuntu main archive doesn't include all old versions, but other mirrors do. Here are some quick steps that let you run official binaries from Jammy under Kinetic to work around this issue until grub2 catches up and/or they tweak compression, or make compression more easily tunable.

wget https://ubuntu.repo.cure.edu.uy/mirror/pool/main/i/initramfs-tools/initramfs-tools-bin_0.140ubuntu12_amd64.deb
wget https://ubuntu.repo.cure.edu.uy/mirror/pool/main/i/initramfs-tools/initramfs-tools-core_0.140ubuntu12_all.deb
wget https://ubuntu.repo.cure.edu.uy/mirror/pool/main/i/initramfs-tools/initramfs-tools_0.140ubuntu12_all.deb
dpkg -i initramfs-tools-bin_0.140ubuntu12_amd64.deb
dpkg -i initramfs-tools-core_0.140ubuntu12_all.deb
dpkg -i initramfs-tools_0.140ubuntu12_all.deb
apt-mark hold initramfs-tools-bin
apt-mark hold initramfs-tools-core
apt-mark hold initramfs-tools
update-initramfs -u

Afterwards, big drop in initrd size. 34% smaller. I am definately getting those fractions of a second back on NVME boot.
-rw-r--r-- 1 root root 111203941 Oct 30 18:16 initrd.img-5.15.0-52-generic
-rw-r--r-- 1 root root 79034965 Oct 31 22:50 initrd.img-5.19.0-23-generic

Sometime down the road, when this bug is closed, you will want to un-hold these to restore the lastest packages

 apt-mark unhold initramfs-tools-bin
 apt-mark unhold initramfs-tools-core
 apt-mark unhold initramfs-tools