Re: [gentoo-dev] usr merge

[Canek Peláez Valdés]

On Sat, Apr 9, 2016 at 11:09 AM,  <waltdnes@××××××××.org> wrote:
> On Sat, Apr 09, 2016 at 07:11:31AM -0400, Rich Freeman wrote
>
>> It was simply a recognition that we were already in a state where
>> booting a system without /usr mounted early can cause problems.
>
>   For certain edge cases... yes.

Edge cases? According to whom?

> But they were already using initramfs
> or merging /usr into /.  I'm talking about the 95% who don't really need
> it.

Do you have *ANY* source for that 95%?

>
>> I never really got the mentality that using an initramfs is a burden.
>
>   One more piece of software that can go wrong.  You have to
> maintain+configure it; e.g. sync software and library versions with
> what's on the rest of the system.

Everything can go wrong; an initramfs is actually a really easy piece
of software to automatize and debug if it goes wrong.

>> An initramfs is just a secondary bootloader for userspace.  I almost
>> always use them even if I'm just booting a VM with a single partition
>> on it.  If something goes wrong you can fall back to a shell in the
>> initramfs and it is like having a rescue disk built into your system
>> disk.
>
>   There is single-user mode for rescue.

Which could fail if, for some reason, you need *something* from /usr
and it hasn't been mounted. And *something* is becoming *anything*,
whether you like it or not.

>> For a more complex setup it is much more robust than relying on
>> the kernel to find your root, and it also lets you build with a more
>> module-based kernel, which has some benefits as well even if you build
>> kernels tailored to each host.
>
>   I have "Production" and "Experimental" entries in my LILO menu.  A new
> kernel is always set up as the "Experimental" entry.  After running
> several days without problems, I run a script which copies the data from
> the "Experimental" portion to "Production".

You use LILO. That means, you don't use UEFI. That means, almost
certainly you don't use recent hardware.

Walter, *YOU* are the 5% edge case. Many people are running UEFI only
hardware, and the number will only increase, since BIOS *is* dead.

>   The only time my system had problems "finding root" was years ago when
> the switch from /dev/hd* to /dev/sd* took place.  The "Experimental"
> boot with the new kernel died.  I booted "Production", read the mailing
> list, changed "hd" to "sd" for the "Experimental" entry, and rebooted.
> After several days without problems, I made the same change to the
> "Production" entry, and copied the "Experimental" portion to
> "Production".

That was the only time *FOR YOU*. But, as I stated above, you are the
5% edge case; the Gentoo devs need to think about the general case,
starting with their own systems so they can do their jobs. I bet most
of them are on UEFI.

Nobody anywhere is telling you what to do with your systems (nor would
they in the future). The Gentoo devs only are saying that if by having
separated /usr without an initramfs, you risk screwing your system,
and if that happens, you are on you own.

Regards.
-- 
Dr. Canek Peláez Valdés
Profesor de Carrera Asociado C
Departamento de Matemáticas
Facultad de Ciencias
Universidad Nacional Autónoma de México