David Wright composed on 2021-04-13 09:52 (UTC-0500):
> On Sun 11 Apr 2021 at 14:33:22 (-0400), Felix Miata wrote:
>>> On Thu 08 Apr 2021 at 14:37:59 (+0200), Marco Ippolito wrote:
>>>> What would you consider in your future planning regarding sizing /boot?
>> root@asa88:/boot# du -sh .
>> 769M .
>> root@asa88:/boot# dpkg -l | grep linux-image-4 | wc -l
>> 10
> Perhaps it should be pointed out that it's atypical to maintain such
> a large number of individual systems on one machine. ISTR your having
> more than a score of root filesystem partitions on one of your disks …
Only a small number of my "disks" have fewer than 10 total partitions. The only
installed one I can think of with only one / is on an inherited laptop. The vast
majority have more than 10 / filesystems. I have more than one with 40+ total.
I have a working Pentium III with 120G and 80G disks with 55 total between them,
40 / between them, that I just booted Debian 4 Etch on today for the first time
in
many moons. It has a separate /boot/ for Etch only, 204MB, with 90% freespace
and
3 installed kernels:
# ls -Gg /boot
total 18198
-rw-r--r-- 1 882748 Sep 27 2005 System.map-2.6.12-1-386
-rw-r--r-- 1 720074 Dec 4 2006 System.map-2.6.18-3-686
-rw-r--r-- 1 722037 May 10 2007 System.map-2.6.18-4-686
-rw------- 1 512 Dec 26 2005 backup_mbr
lrwxrwxrwx 1 1 Nov 14 2006 boot -> .
-rw-r--r-- 1 61577 Sep 26 2005 config-2.6.12-1-386
-rw-r--r-- 1 71331 Dec 4 2006 config-2.6.18-3-686
-rw-r--r-- 1 70781 May 9 2007 config-2.6.18-4-686
drwxr-xr-x 2 2048 Dec 14 05:32 grub
lrwxrwxrwx 1 23 Nov 14 2006 initrd.img -> initrd.img-2.6.12-1-386
-rw-r--r-- 1 1449984 Jan 11 2006 initrd.img-2.6.12-1-386
-rw-r--r-- 1 4496652 Dec 9 2006 initrd.img-2.6.18-3-686
-rw-r--r-- 1 4500813 Jun 14 2007 initrd.img-2.6.18-4-686
drwx------ 2 12288 Dec 12 2005 lost+found
-rw-rw-r-- 1 180856 May 13 2011 memtest.420
-rw-r--r-- 1 94356 Feb 2 2005 memtest86.bin
-rw-r--r-- 1 621056 Aug 16 2013 message
-rw-r--r-- 1 621056 Aug 16 2013 message-131m4-tux
-rw-r--r-- 1 128000 Dec 26 2005 message.prv
-rw-r--r-- 1 76803 Feb 12 2015 rdsosreport.txt
lrwxrwxrwx 1 20 Nov 14 2006 vmlinuz -> vmlinuz-2.6.12-1-386
-rw-r--r-- 1 1275119 Sep 27 2005 vmlinuz-2.6.12-1-386
-rw-r--r-- 1 1259920 Dec 4 2006 vmlinuz-2.6.18-3-686
-rw-r--r-- 1 1261213 May 10 2007 vmlinuz-2.6.18-4-686
Known to still be working with at least one OS updated less than a year ago 32
bit
systems number 12 here currently. 64 bit count is 28.
>> root@asa88:/boot# dpkg -l | grep linux-image-4
>> ii linux-image-4.19.0-1-amd64 4.19.12-1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-10-amd64 4.19.132-1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-12-amd64 4.19.152-1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-14-amd64 4.19.171-2 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-2-amd64 4.19.16-1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-4-amd64 4.19.28-2 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-5-amd64 4.19.37-5+deb10u2 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-6-amd64 4.19.67-2+deb10u2 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-8-amd64 4.19.98-1+deb10u1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
>> ii linux-image-4.19.0-9-amd64 4.19.118-2+deb10u1 amd64 Linux 4.19 for
>> 64-bit PCs (signed)
> … and I suppose that the contents of one of these partitions might
> explain why you might still boot, say, a 4.19.12 kernel.
Only one I can think of: the possibility to bisect without having to build a
kernel, or download anything to an out of support release. Essentially, bootable
archives on real hardware.
>> Keep in mind, on average, each kernel release is larger than the last.
> True, both the kernel itself and the amount that gets put into the
> initrd. But also bear in mind that:
> . if these kernels are all for just one system (which they appear to be),
> several of the older ones could be uninstalled, but the .debs kept for
> later reinstallation if and when required,
> . if the kernels were for many different systems on the one machine,
> the System.map/config/initrd.img/vmlinuz ensemble for several of
> them could simply be moved to the day-to-day system's archive,
> and copied back into place as and when required, to boot a
> different, less frequently used system.
> I think it's rare indeed to have to choose between ten different
> kernels at the drop of a hat when booting up one system. What would
> the use case be?
>
The example in this thread is probably my only instance of so many Debian
kernels
kept installed on one /. Reinstalling at some later time introduces the
possibility of impact from subsequent changes in the construction toolchain.
My sharing here was a simple matter of providing real world data for a
calculation
of required space for a separate /boot/ filesystem.
I remember when 75MB was enough for more than two kernels, while now it might
not
be enough for one.
--
Evolution as taught in public schools, like religion,
is based on faith, not on science.
Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!
Felix Miata *** http://fm.no-ip.com/
