Gentoo Archives: gentoo-user

From: "Canek Peláez Valdés" <caneko@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] bindmount or symlink?
Date: Tue, 13 Mar 2012 05:46:56
Message-Id: CADPrc81C3LS1TbHt01-aVkUXdL-2JuWXhBH2NwtMeK7kTjmXbw@mail.gmail.com
In Reply to: Re: [gentoo-user] bindmount or symlink? by Pandu Poluan
1 On Mon, Mar 12, 2012 at 11:39 PM, Pandu Poluan <pandu@××××××.info> wrote:
2 > On Tue, Mar 13, 2012 at 12:11, Canek Peláez Valdés <caneko@×××××.com> wrote:
3 >> On Mon, Mar 12, 2012 at 11:04 PM, Pandu Poluan <pandu@××××××.info> wrote:
4 >>> I am seriously thinking of splitting the storage of directories under /usr,
5 >>> e.g., /usr/portage and /usr/source actually living somewhere else, on
6 >>> different partition and different filesystem. Let's say something mounted on
7 >>> /mnt/Persistent.
8 >>>
9 >>> My question: should I use bindmount or symlinks to do that? What's the
10 >>> drawbacks/benefits for either?
11 >>
12 >> I'm sorry, I don't understand. What's the problem of having the
13 >> following in /etc/fstab?
14 >>
15 >> LABEL=Portage   /usr/portage            ext4            noatime,auto                    0 2
16 >> LABEL=Source            /usr/source             ext4            noatime,auto                    0 2
17 >>
18 >> (Replace LABEL=Portage with /dev/sda7, if you want to.)
19 >>
20 >> Why do you need to bindmount or link the directories when you can
21 >> mount them wherever you want?
22 >>
23 >
24 > Because I am avoiding "single partition per directory". And a slight
25 > mistake in my original email, it's not just /usr but also /var (and
26 > other root-based directories that will not interfere with boot-up /
27 > operations)
28 >
29 > Let me give an example:
30 >
31 > Let's say I have /dev/sdc and /dev/sdd, both having single partition
32 > each (/dev/sdc1 and /dev/sdd1).
33 >
34 > /dev/sdc1 will be formatted reiserfs mounted into /mnt/Persistent1
35 >
36 > /dev/sdd1 will be formatted ext4 mounted into /mnt/Persistent2
37 >
38 > Directories not really necessary for daily operations, such as
39 > /usr/src, /usr/portage, /var/db/pkg, and so on and so forth, will each
40 > be a subdir under either /mnt/Persistent1 or /mnt/Persistent2
41 > according to each directory's nature.
42 >
43 > Let's take the example of /usr/src ... I can either make /usr/src a
44 > symlink to /mnt/Persistent1/src, or bindmount /mnt/Persistent1/src to
45 > /usr/src
46
47 All of that sounds incredible complicated. Interesting choice of
48 partition handling.
49
50
51 > What will be the benefits/drawbacks for bindmount vs symlink?
52
53 In my experience, and if you are not dealing with NFS, no respectable
54 program cares about a dir being a symlink, so I would use symlinks
55 (they are easier to handle).
56
57 Regards.
58 --
59 Canek Peláez Valdés
60 Posgrado en Ciencia e Ingeniería de la Computación
61 Universidad Nacional Autónoma de México