Re: [gentoo-dev] Changing order of default virtual/udev provider

[Rich Freeman <rich0@gentoo.org>]

On Tue, Feb 9, 2016 at 3:43 AM, Kent Fredric <kentfredric@gmail.com> wrote:
>
> A pure udev system is in comparison, much simpler than a systemd system.

I don't buy that at all.  In systemd you have a unified object model
across device nodes, mountpoints, services, and cron jobs.  In the
alternate model you have completely different implementations of all
of those, each with their own configurations and behaviors.

>
> And that's much of the beauty of OpenRC. Its simple, it achieves the
> same goals as Systemd and Upstart, etc, but does so with a lot less
> mechanics under the hood, and doesn't clutter up systems with features
> you don't need prematurely.

OpenRC doesn't achieve MANY of the goals of systemd.  Maybe you don't
personally care about some of them, but you really can't compare the
feature sets at this point.

> And there are great benefits from simplicity over complexity.

Absolutely.  It is great to create a text file and symlink it in a
directory named after a service to make that service auto-restart, or
have a memory limit, or set an IO priority for that service.  It is
great to not have to think about anything to have just about all your
processes organized into a sensible cgroup hierarchy.  It is great to
be able to tweak one config file to ensure that users who log out of a
system can't leave any processes behind.

It is great to be able to tweak something in policykit and change
things like who can shut down the system, or who can restart a
service.

The simplicity of systemd comes from the fact that it has brought what
used to be a collection of many independent tools under one roof, and
created a converging set of interfaces for all of them.

> And a lot of Gentoo is surprisingly simple: Like our use of bash
> scripts for recipies to build things, like using rsync to deploy/relay
> not just those recipies, but security notices and  news items, which
> are themselves reasonably simple formats.

Well, one thing about Gentoo that certainly isn't simple is our init.d scripts.

Compare this:
http://pastebin.com/sSDtpF4t

With this:
http://pastebin.com/Lfn8r7qP

Systemd does the job in 10% of the code (and half of it is a comment),
and doesn't implement its own service polling and killer script during
shutdown independently for every service (not that every init.d script
even does this - most of them will just leave orphans behind, and
systemd will catch orphans that even the lengthy init.d script for
apache misses).

>
> The only preference I see here is the preference to not have and
> install things your system has no use for, which I find an odd
> preference to be complaining about, and depending on your system
> requirements, that may also be not so much "preference".
>

And hence my suggestion that we simply get this stuff out of the
stage3s in the first place.  Then everybody can just pick the
implementation that best suits their requirements.

If you want to talk about default providers, the most straightforward
one to use is systemd.  It is what people are going to be used to
coming from other distros, it is what every upstream package expects
to be running anyway, and it is the simpler tool that does everything
that most people want.

For people who want a more exotic configuration, there are
alternatives, and Gentoo should certainly support using them as long
as people care to maintain them.

-- 
Rich