Re: RFC: New required package: libblkid1
On Wed, Mar 19, 2003 at 08:58:00PM -0500, Stephen Frost wrote:
> * Theodore Ts'o (firstname.lastname@example.org) wrote:
> > Any comments, complaints with this plan?
> Just to whine about yet another file being written to in /etc and to ask
> if blkid.tab will be very large? Doesn't sound like it, just checking.
It's one line per block device, and it's in XML format:
<device DEVNO="0x0302" TIME="1047622800" LABEL="root" UUID="60cc84b5-f7df-43e6-b6f3-268cdef48de1" SEC_TYPE="ext3" TYPE="ext2">/dev/hda2</device>
<device DEVNO="0x0303" TIME="1047483818" TYPE="swap">/dev/hda3</device>
<device DEVNO="0x0305" TIME="1047483818" LABEL="var" UUID="a4ce30dd-01d2-4eac-b235-bddd0135b899" SEC_TYPE="ext3" TYPE="ext2">/dev/hda5</device>
<device DEVNO="0x0301" TIME="1047483818" UUID="082D-26E3" TYPE="vfat">/dev/hda1</device>
If you have a system with 2000 block devices then the blkid.tab file
will be around 160k, but that's not going to be the typical case. But
in that case where you have 2000 block devices, (A) you really want to
use UUID= or LABEL=, since managing that number of devices is not
pleasant, but (B) the implementation of searching all block devices
when using UUID= and LABEL= is really painful.
> Since you'd be adding to the /etc written stuff do you have any comment
> on the thread that was on here recently about moving things which are
> written to out of /etc and into somewhere else (such as /run)?
I think /run is stupid. People who think that /etc should only be
config files are being just way too anal. Yeah, the FHS didn't
specify that there were certain writeable files which were necessary
during the boot process before /usr and /var is mounted. However, the
FHS also does specifically calls out the following writeable files as
being in /etc: adjtime, mtab.
I ask you: what specific problem does creating a new top level
directory solve, other than making the making the anal-rentative FHS
lawyers happy? /run and /etc have to be on the root partition, and
the files need to be persistent, so it can't be a memory based
filesystem. (/mem is silly since there are very few writeable files
that don't need persistent across files.) Why do we really want to
separate configuration files such as /etc/fstab from files like
/etc/mtab? Being gratuitously different from other Unix systems just
to satisfy some abstract principle that /etc "should be configuratoin
files only" is just an idiotic idea.