[GTALUG] long war story: growing the ESP (/boot/efi)

[D. Hugh Redelmeier]

| From: o1bigtenor via talk <talk at gtalug.org>

| On Wed, Jul 7, 2021 at 5:52 PM D. Hugh Redelmeier via talk
| <talk at gtalug.org> wrote:
| >
| > == why you might wish to grow the ESP ==
| >
| > In a UEFI system, booting starts with the ESP (EFI System Partition).
| >
| > Apparently Windows creates a 100M ESP during a fresh install.

| Does this also happen if there is no Win quotient in the partition?

If you are asking: how much does Windows add to the requirement for
space?  I don't know.  Also: each manufacturer may decidedd to put
more or less diagnostic software in the ESP too.

If you are asking: how big an ESP would a Linux installation create?
I don't know.  The installers I use give a suggestion but let me
override.

What's a good size for an ESP?  My current guess is that 200M is
plenty and isn't too wasteful given how large disks are these days.

On my XPS 15 notebook (the one that prompted the adventure):
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/sda2         200623 95057    105566  48% /boot/efi
(More was used during the firmware update.)

On my desktop SSD:
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/sdb2         364544 65436    299108  18% /boot/efi
(The last firmware update was in 2014.)

Blue sky uses of ESP:

I imagine, if you want a lean installation, you could eliminate grub and 
boot a linux kernel directly from UEFI.

- the kernel and initramdisk files would have to live in the ESP

- the kernel wuld have to be in .efi form

I'd love to get rid of a whole layer of software from the booting process.  
What does grub2 do for us?

- select what to boot (but most UEFI software lets you do that too)

- place the OS on filesystems/partitions other than the ESP

- fiddle about when things go wrong.  Especially when that thing is grub