On Thu, Dec 17, 2015 at 05:54:52PM -0800, Brendan Conoboy wrote: > On 12/17/2015 05:46 PM, Zbigniew Jędrzejewski-Szmek wrote: > >On Thu, Dec 17, 2015 at 05:34:31PM -0800, Brendan Conoboy wrote: > >>On 12/17/2015 05:27 PM, Zbigniew Jędrzejewski-Szmek wrote: > >>>On Thu, Dec 17, 2015 at 04:13:06PM -0800, Brendan Conoboy wrote: > >>>>On 12/17/2015 01:43 AM, Harald Hoyer wrote: > >>>>>For docker containers, or containers, which don't want systemd, the current > >>>>>"Requires: systemd" in a lot of packages is preventing building a minimal image. > >>>>> > >>>>>To improve the situation, we could make use of the new rpm weak dependencies. > >>>>>So the > >>>>> > >>>>>Requires(post): systemd > >>>>>Requires(preun): systemd > >>>>>Requires(postun): systemd > >>>>> > >>>>>would become > >>>>> > >>>>>Recommends: systemd > >>>>>OrderWithRequires(post): systemd > >>>>>OrderWithRequires(preun): systemd > >>>>>OrderWithRequires(postun): systemd > >>>>> > >>>>>With this in place, kickstart files could omit systemd. > >>>>> > >>>>>The downside is: > >>>>>- if systemd is installed afterwards, the %post scripts do not trigger > >>>>>- packages, which need systemd-tmpfiles or systemd-sysusers could not be converted > >>>>> > >>>>>If systemd is removed before the other packages, I don't see a problem. > >>>>>There are only leftovers in /etc/systemd. > >>>>> > >>>>>To prevent having a non-bootable system (not container), we could let the > >>>>>kernel.spec have a Requires on systemd. > >>>>> > >>>>>Comments? Please discuss. > >>>> > >>>>I haven't seen a lot of downside brought up in this thread. If the > >>>>only objections people have is that it doesn't facilitate their > >>>>personal use cases those don't seem like real objections. Is > >>>>anybody going to be really negatively impacted by such a change? > >>>> > >>>>For my part I'd like to see this happen, not just for packages > >>>>requiring systemd, but for all packages where "Requires" is really > >>>>stronger than necessary. Now that we have soft dependencies it > >>>>would be nice to go through and move to Recommends where software > >>>>continues to function in some reduced capacity. > >>> > >>>For some packages "reduced capacity" because of lack of systemd.rpm > >>>means "doesn't even get started as expected" or "crashes on > >>>start with permission errors" or "cannot write logs" or similar. > >>>Like Lennart and Neil said, utilities provided by systemd.rpm are the > >>>basis which allows many things to "just work". This is so obvious > >>>that it is assumed implicitly in this disussion, and it's hardly > >>>"personal use cases". > >> > >>If the software crashes on start with permission error that's not > >>really working in a reduced capacity. > > > >Exactly. So Required(post/pre/preun):systemd cannot currently be > >changed to Recommmends, at least in the general case. > > It's not clear the cases you have in mind are the general case. > There is doubtless a happy medium here, though. Perhaps it is > opening up the policy to promote Recommends, but leave it to > packager discretion. Recommends largely behaves like requires, so > it's fairly low risk to err on the side of recommends. Currently service enablement is very much centralized. With the recent changes (https://fedoraproject.org/wiki/Packaging:DefaultServices) and the move of presets to fedora-release this is even more true than before. Various editions and spins modify the presets to disable/enable stuff they need, and this hinges on all packages behaving uniformly. Letting individual packages make the choice would break this centralization; packages are not the right level to make this choice. Zbyszek -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx http://lists.fedoraproject.org/admin/lists/devel@xxxxxxxxxxxxxxxxxxxxxxx
