[arch-general] Think twice before moving to systemd

[Tom Gundersen]

Felipe,

On Aug 15, 2012 3:35 AM, "Felipe Contreras" <felipe.contreras at gmail.com>
wrote:
> I tried systemd a while ago in a brand new machine with Arch Linux and
> the boot was *much slower*. After some exchanges with Lennart
> Poettering and other people in Google+[1], it became clear I was on my
> own. Eventually I found the culprit: Fedora uses CONFIG_HZ_1000, and
> Arch Linux uses CONFIG_HZ_300. It became clear to me that systemd was
> not ready for prime time, it wasn't thoroughly tested in a lot of
> machines, and if you have problems Lennart Poettering will blame you
> (PulseAudio sounds familiar?).

Do you have a link to a proper bug report for this issue? I tried reading
the Google+ thread but I couldn't stomach how rude you were in each of your
messages (including the first one) so stopped reading.

> systemd was the reason I stopped using Fedora in the first place; when
> they moved to it my machine stopped booting reliably. My configuration
> was non-standard (a single encrypted partition), so I guess they never
> tested that. Similarly, I expect many Arch Linux users to bite these
> corner-cases.

Please note that we have waited much longer than Fedora did to make sure
the corner cases have been taken care of. Is this problem still an issue,
or is it just FUD? Link to (current) bug report?

> Finally, it's much harder to debug. If you have a problem you will not
> be able to open a script and figure out what is happening, and perhaps
> modify it, and debug it. You would be greeted with an unmodified
> binary, and the source code would be along these lines:
>
>
http://cgit.freedesktop.org/systemd/systemd/tree/src/remount-fs/remount-fs.c

As someone who has spent a lot of time debugging both, I much prefer
systemd. I think you are being disingenuous here, surely you don't have a
problem reading C?

> I'm sure in due time systemd will be ready, and will have nice
> advantages, but I doubt that's the case right now. Has anybody looked
> into the CONFIG_HZ issue? I doubt that.

This is the first I hear of it. I'd be interested to follow up if there is
a proper bug report without unnecessary hostility.

> I was expecting more from the Arch Linux community, something along
> the lines of Google's analysis to pick to mercurial[2], but so far I
> have only seen a couple of people saying +1 in the development mailing
> list, with barely any explanation at all. Such an important move (one
> that might make users' machines stop booting) should warrant at least
> an analysis of some sort, with clear advantages. Would it not?

We provided systemd optionally for a long time, as you know. Its pros and
cons have been discussed at the various making lists at great length. A
significant portion of our userbase has switched to it, and no serious
issues seem to remain, based on the feedback we have been getting. Each dev
will have had the possibility of trying it, and researching it. They will
have done their own analysis on which the +1s are based. I see no value in
providing an official public analysis. That's not how we work, and it would
not help in the decision making at this point.

That's not to say that an analysis would not be an interesting read, and
I'm sure people like Allan our Jason will provide some excellent blog posts
about this at some point.

> At the moment I am unconvinced; does systemd has any *real* advantage?
> I don't think so; the potential of breakage outweighs the "supposed"
> advantages, and I think a proper analysis would show that.

If you find any issues, please report bugs. Except for that, all I can say
is that no one set out to convince you, and I'm sure Google will find you
discussions/analysis/code if you are genuinely interested.

Tom