[Mageia-dev] [Mageia 2 specifications] Systemd or not systemd

[Colin Guthrie]

'Twas brillig, and Eugeni Dodonov at 14/07/11 02:47 did gyre and gimble:
> On Tue, Jul 12, 2011 at 09:48, Colin Guthrie <mageia at colin.guthr.ie
> <mailto:mageia at colin.guthr.ie>> wrote:
> 
>     'Twas brillig, and Eugeni Dodonov at 12/07/11 13:15 did gyre and gimble:
>     > If nobody objects, I could help with that. Mandriva certainly gave a
>     > large experience on how to integrate systemd into the system without
>     > killing traditional sysvinit alternative.
>     >
>     > It would also be extremely interested to have native systemd services
>     > which use most of systemd features (like sound and alsa scripts, which
>     > we discussed with Colin and Andrey Borzenkov some months ago but never
>     > got to implement properly).
> 
>     Massive +1 for systemd and massive +1 Eugeni wanting to help out! \o/
> 
>     I'll try and help out in bits and bobs too, tho' time is always a
>     problem!
> 
> 
> 
> Ok, some n00b questions arise from my part, sorry if they seem too basic
> - I am only catching up with mga style of development :).
> 
> Systemd 30 is out, with lots of nice changes, so I think we should use
> it now as we are quite early in the release cycle. It is working on my
> machine, but before doing something about it, I prefer to hear opinions :).

Well, IMO (for what it matters) I'm massive for using it ASAP!

> Firstly, systemdrequires udev >= 172, what is the policy to update it?
> According to 'mgarepo maintdb get udev', it has no maintainers, does
> anyone objects if I grab/update it as well?

I think that would be most welcome!

> Secondly, what should be the correct way of supporting systemd in a
> package? In Mandriva, I thought on adding a --with flag to
> enable/disable systemd, but in most cases it does (almost) nothing. All
> services which want to support systemd only need to place their files
> into /lib/systemd - and that's it. Should we support opting-out of
> systemd in specs? I believe fcrozat is having the same dilemma in SuSE
> now as well, and he settled on some common packaging macros.

IMO, unless something goes horribly wrong with systemd (which I very
seriously doubt will happen - it's actually been amazing to watch this
project from birth to wide adoption) I'd say we just jump right in and
package the units unconditionally. They don't really take up much space
and do nothing if you choose to not use it for the time being. I think
by mga3 we'll likely *only* offer systemd (if not in mga2), so I'd say
putting in effort to opt out now is pretty much not going to be worth it.

If anyone else feels super strongly to the contrary, speak up now or
forever hold your peace :D

> Almost finally, should the systemd files belong to the main package, the
> same way as they do with initscripts-based one (e.g., the package would
> provide /lib/systemd/system/%{name}.service together with
> %_sysconfig/rc.d/init.d/%{name} for example), with no extra subpackages
> or flags - or should all systemd-specific files go into %{name}-systemd
> package for example? What do you think?

I vote to put them in the same place as the initscripts-based ones. As I
predicted above, I reckon it won't take too long for systemd to be the
only system offered and obsoleting all those subpackages would be a bit
of a PITA down the line. And if systemd isn't used those files do
nothing, so no harm done.

> And finally, what does seems to be the best way of starting to use
> systemd in cauldron? I have thought on 3 alternatives:
>  - easy way, only having it packaged, but not
> providing/obsoleting/conflicting with sysvinit. This way, it will work
> when kernel is booted with init=/bin/systemd (the least invasive way)
>  - compatible way (like in Mandriva) - it is available, systemd-sysvinit
> conflicts with sysvinit, so if someone installs systemd-sysvinit,
> sysvinit goes away and systemd is run by default. This seems to be the
> most sane way to me (but I could be biased), and it is easiest one for
> testing
>  - ultimate way - systemd provides and obsoletes sysvinit and its
> goodies. This way, systemd will be the only one (e.g., highlander
> style). This is how fedora did it if I am not mistaken, but I am not
> sure if it the best way.
> 
> So, that's it for now from my part..

I'd like option 2 please! :) It doesn't exclude using option 1 along
with it (I was doing this for a while), so it's most flexible.

If all goes well for those testing it, we can vote on whether we jump in
with both feet :)

That's my take on it anyway!

:)

Col



-- 

Colin Guthrie
mageia(at)colin.guthr.ie
http://colin.guthr.ie/

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