Gentoo Archives: gentoo-dev

From: "Michał Górny" <mgorny@g.o>
To: gentoo-dev@l.g.o
Cc: polynomial-c@g.o, Alex Alexander <wired@g.o>
Subject: Re: [gentoo-dev] rfc: locations of binaries and separate /usr
Date: Sun, 08 Jan 2012 09:33:31
Message-Id: 20120108103345.382b8db3@pomiocik.lan
In Reply to: Re: [gentoo-dev] rfc: locations of binaries and separate /usr by Lars Wendler
1 On Sun, 8 Jan 2012 00:47:21 +0100
2 Lars Wendler <polynomial-c@g.o> wrote:
3
4 > Am Freitag 06 Januar 2012, 17:07:20 schrieb Alex Alexander:
5 > > On Fri, Jan 06, 2012 at 08:35:32AM -0500, Rich Freeman wrote:
6 > > > On Thu, Jan 5, 2012 at 5:36 PM, Alex Alexander <wired@g.o>
7 > > > wrote:
8 > > > > If people are really interested in keeping a tight, self
9 > > > > contained root, we need to:
10 > > > >
11 > > > > - establish a [tight] list of software we consider critical
12 > > > > for /
13 > > > > - fix/patch software in that list so it can run without /usr
14 > > > > there
15 > > > > - create /bin => /usr/bin/ symlinks for above software
16 > > > > (simplifies things if packages start hardcoding /usr/bin here
17 > > > > and there)
18 > > > > - move everything else in /usr/bin/
19 > > >
20 > > > You're missing one thing:
21 > > >
22 > > > - establish a list of all the configurations that will actually
23 > > > work with this self-contained root
24 > > >
25 > > > I think this is why there is so much disagreement over whether
26 > > > this is a good move. If you have a really simple configuration,
27 > > > then the self-contained root concept works reasonably well
28 > > > (though apparently we'll have to heavily patch newer versions of
29 > > > udev or abandon it to sustain this).
30 > > >
31 > > > However, if you have a very complex configuration the current
32 > > > self-contained root is already broken and you need an initramfs
33 > > > anyway. For in-between cases things might work now but that is
34 > > > likely to change as upstream moves on.
35 > > >
36 > > > The binary distros don't have users tweaking their kernels and
37 > > > init scripts, so they basically have to design for worst-case.
38 > > > Gentoo can get away with designing for more of an average case
39 > > > since we just tell anybody with a complex case to go read a howto
40 > > > and configure what is necessary (and we like to do that stuff
41 > > > anyway).
42 > > >
43 > > > We can choose not to like it, but it sounds like maintaining a
44 > > > self-contained root for even the typical case will become
45 > > > untenable. Those who argue that having /usr on a separate
46 > > > partition simply shouldn't be supported are basically just saying
47 > > > that our "self-contained root" should include everything in /usr
48 > > > which seems to defeat the whole point of a "self-contained root"
49 > > > anyway.
50 > > >
51 > > > It seems to me that the most reasonable approach is to not force
52 > > > the issue, but not deviate greatly from upstream either. That
53 > > > means accepting that over time the rootfs will become less and
54 > > > less capable of working on its own, and immediately improving
55 > > > tools like dracut to overcome these limitations. Users who can
56 > > > get away with it can avoid using an initramfs, at least for a
57 > > > time.
58 > > >
59 > > > Sure, it is all open source, and Gentoo can swim upstream if we
60 > > > REALLY want to. However, this only works if developers are
61 > > > willing to spend the time constantly fixing upstream's tools. It
62 > > > sounds to me like the maintainers of packages like
63 > > > udev/systemd/etc want to actually move in the same direction as
64 > > > upstream so in practice I don't see that happening.
65 > > >
66 > > > Now, Gentoo is about choice, so one thing we should try to do as
67 > > > much as possible is understand the limitations of the various
68 > > > configurations and make it clear to users when they do and don't
69 > > > need an initramfs. To be honest, tight coupling worries me more
70 > > > than the /usr move, since that has a lot more potential to
71 > > > constrain the choices we can offer our users (which is a great
72 > > > deal of the value that Gentoo offers). I understand its
73 > > > advantages, but it seems somewhat contrary to "the unix way."
74 > >
75 > > That's why I wrote "tight list". I do not expect the self-contained
76 > > root to be able to handle everything /usr (or a complete initramfs)
77 > > would. What it could and couldn't do is something that needs to be
78 > > decided, but some work is already done there - it's just a bit
79 > > messy and incomplete and because most people don't care it keeps
80 > > getting worse.
81 > >
82 > > The important thing here is to make a clear definition of where we
83 > > draw the line and make sure things work the way we want them to.
84 > >
85 > > I agree with you in that at some point patching may become too time
86 > > consuming, but I still believe that if we do this properly, with a
87 > > well-defined plan and list of packages we want to keep in / (with
88 > > symlinks to be compatible with whatever others are trying to do), we
89 > > won't be alone in this. Gentoo may be one of the most hardcore
90 > > power-user distros out there, but we're certainly not the only one.
91 > >
92 > > Now, if only we had people interested enough in doing this... :)
93 >
94 > I'm interested in everything which prevents such kind of insanity
95 > from Gentoo. So count me in as volunteer keeping /bin, /sbin and /lib
96 > in Gentoo and systemd away from it.
97 > As long as we keep trying and working hard I'm sure we can do the
98 > workload that might come across when blind upstreams start adopting
99 > those foolish systemd/GnomeOS ideas...
100
101 From which point this was systemd/GnomeOS ideas? As far I can see, this
102 was completely irrelevant, separate Fedora idea. But with scapegoat,
103 everything seems better, doesn't it?
104
105 Does working hard involve compiling even more packages statically?
106 Considering that we all know the drawbacks of static linkage, this is
107 definitely not insanity.
108
109 --
110 Best regards,
111 Michał Górny

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Re: [gentoo-dev] rfc: locations of binaries and separate /usr Enrico Weigelt <weigelt@×××××.de>