[systemd-devel] 'Offline System Updates' examination

[Alexander E. Patrakov]

2012/6/21 Lennart Poettering <lennart at poettering.net>:
> If source based distros want to implement this I'd probably recommend
> them to compile everything in the system, and only do the final step,
> the installation as part of the system-update step.

The problem is that your recommendation (if I understand it correctly)
does not work, at all.

Suppose that there are two packages to update, icu and libreoffice.
Libreoffice depends on icu, and for the reason of simplicity of the
argument let's pretend that there are no other packages in the system
that use icu. If your recommendation is to be followed literally, the
package manager needs to compile icu (thus creating either a binary
package or a tree where it can run "make install" later), compile
libreoffice the same way, then install both results later. However,
this would lead to installation of libreoffice compiled against the
old icu, which may or may not work. Libreoffice should really be
compiled with the new icu already installed, and this is directly
against the "install all updates in one big batch" approach.

So, could you please clarify the recommendation in the aspect of
dealing with such dependencies? The "install to btrfs snapshot"
approach would handle this correctly by installing each package as
soon as it gets compiled.

-- 
Alexander E. Patrakov