stop rechunking with hhd/legacy-rechunker and use rpm-ostree rechunker

[renner0e]

we need to implement this on aurora in 2026

zirconium-dev/zirconium@05f3e9c

Basically 2 changes at once, add a workaround we will probably have to keep for a very long time to undo nastiness of the hhd/rechunker (documented in the files of the mentioned commit) and utilize the rpm-ostree rechunker to reduce our update deltas again.

Related upstream issues/PRs:

• [BUG] build-chunked-oci does not place initramfs in its own layer coreos/rpm-ostree#5544
• container-encapsulate: Mark initramfs as exclusive component coreos/rpm-ostree#5535
• build-chunked-oci crashes if target image used as baseline and xattrs for non-rpm contents has changed coreos/rpm-ostree#5545
• ostree-ext: Make new packing if using prior build fails bootc-dev/bootc#1880
• ostree-ext: Failed assertion in Chunking::process_mapping bootc-dev/bootc#1885

This would make things considerably nicer

• feat: --previous-build-manifest option for build-chunked-oci coreos/rpm-ostree#5548

[inffy]

Can't we go straight to this, and not deal with the legacy one fork?

[renner0e]

Can't we go straight to this, and not deal with the legacy one fork?

We only update a digest with this one on our end.

I'm hesitant to move over during/right before the holidays because this is a change that could potentially break every users machine and would lead "stuck on black screen issues". Just do it after the holidays is all I'm saying.

[inffy]

Can't we go straight to this, and not deal with the legacy one fork?

We only update a digest with this one on our end.

I'm hesitant to move over during/right before the holidays because this is a change that could potentially break every users machine and would lead "stuck on black screen issues". Just do it after the holidays is all I'm saying.

oh right, yes that is better, not ruin holidays because of this :)

[renner0e]

I would appreciate it if someone rebased their machine to my images to test it:

i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

[Danathar]

I would appreciate it if someone rebased their machine to my images to test it:

i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

I've got a VM of Aurora that I can test it with. Is there anything else specific you would like me to look out for in addition to what you said?

[inffy]

I would appreciate it if someone rebased their machine to my images to test it:
i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

I've got a VM of Aurora that I can test it with. Is there anything specific you would like me to look out for in addition to what you said?

Pretty much that it boots normally.

How old is your VM install, just curious

[Danathar]

I would appreciate it if someone rebased their machine to my images to test it:
i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

I've got a VM of Aurora that I can test it with. Is there anything specific you would like me to look out for in addition to what you said?

Pretty much that it boots normally.

How old is your VM install, just curious

last couple of months. Made it just before the upgrade to 43, but I could easily spin up another if you want to test directly from the latest base.

[inffy]

I would appreciate it if someone rebased their machine to my images to test it:
i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

I've got a VM of Aurora that I can test it with. Is there anything specific you would like me to look out for in addition to what you said?

Pretty much that it boots normally.
How old is your VM install, just curious

last couple of months. Made it just before the upgrade to 43, but I could easily spin up another if you want to test directly from the latest base.

don't worry about it. We have tested few pretty fresh installs and those went fine.

[Danathar]

I would appreciate it if someone rebased their machine to my images to test it:
i.e.

sudo bootc switch ghcr.io/renner0e/aurora:stable-daily

"edge cases" like multiple users in 1XXX range would be nice, manually added groups

I've got a VM of Aurora that I can test it with. Is there anything specific you would like me to look out for in addition to what you said?

Pretty much that it boots normally.
How old is your VM install, just curious

last couple of months. Made it just before the upgrade to 43, but I could easily spin up another if you want to test directly from the latest base.

don't worry about it. We have tested few pretty fresh installs and those went fine.

Thanks. Tried it anyway ;) got an error about multiple entries when it tried to switch images.

[renner0e]

Thanks. Tried it anyway ;) got an error about multiple entries when it tried to switch images.

@Danathar What error did you get?