[oe] /usr merge, stateless systems and atomic updates w/ OpenEmbedded?

[Khem Raj]

On 1/14/17 11:45 AM, Leon Woestenberg wrote:
> Hello all,
> 
> more and more I am liking the approach taken by SuSE snapper (incremental
> but atomic updates using light-weight snapshots on BTRFS) and OSTree
> (incremental atomic updates using a GIT like approach on the source, bsdiff
> for delta updates).
> 
> These are targeting -- but also require -- systems that use the "/usr
> merge" approach, which is a bit controversial, but seems to fit many
> today's use cases; embedded, containers etc.
> 
> GNOME Continuous uses OpenEmbedded with OStree.
> Automotive Grade Linux has started to use Yocto with OSTree.
> 
> Looking back in the mailing lists, I have seen interest and activities in
> and around OpenEmbedded Core since 2013 to support /usr merge, but I am
> unaware of any upstream support for this, or distro's that implement it. Am
> I missing something?

I know archlinux based distros are already symlinking /bin and /lib
/sbin to their counterparts in /usr but I am not sure once you remove
these symlinks things will keep working as usual as there will be a set
of packages assuming these paths and so on.

> 
> Are there any developers here who do use OpenEmbedded with a /usr merge
> approach?
> 
> Regards,
> 
> Leon.
> 
> Some random links I came across:
> http://lists.openembedded.org/pipermail/openembedded-core/2014-December/099616.html
> https://patchwork.openembedded.org/patch/89069/
> http://lists.openembedded.org/pipermail/openembedded-core/2013-August/083595.html
> https://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge/
> https://patchwork.openembedded.org/patch/111129/
>