Re: [gentoo-dev] rfc: locations of binaries and separate /usr

[Olivier Crête]

On Fri, 2012-01-06 at 19:41 -0500, Walter Dnes wrote:
> On Wed, Jan 04, 2012 at 01:51:26PM -0500, Olivier Cr?te wrote
>
> > No no no, the idea is that once all binaries are in /usr, you can easily
> > share /usr between different systems and do updates in a sane way.. You
> > can also mount /usr read-only, but still have / be read-write.
>
>   One size does not fit all.  It breaks Gentoo horribly.  Here's my setup
>
> waltdnes@d530 / $ du -s /usr
> 3057917 usr
>
> waltdnes@d530 /usr $ du -s /usr/portage
> 1394646 /usr/portage
>
> waltdnes@d530 /usr $ du -s /usr/src
> 665069  /usr/src
>
>   In my 3 gig /usr directory, over 2 gigs are devoted to Gentoo-specific
> stuff that a binary distro like Redhat does not require.  What do we do
> if /usr is read-only?  Symlink or bindmount onto it?

You don't understand the purpose of read-only /usr. It has nothing to do
with source vs binary. It is for when you have many machines that are
identical or at least similar.

The idea is that you can mount the same /usr on many machines (using NFS
or something like that). So you can have a relatively small / as a r/w
nfsroot (containing /etc, /var, /tmp, etc, etc), and then share /usr
among all the machines in your cluster or machine room or your many user
desktops.

With the current system, you either have to maintain in sync
the /bin, /sbin, /usr, etc separately, making life harder for everyone.

But clearly, you've never been the sysadmin of that kind of setup.

-- 
Olivier Crête
tester@g.o
Gentoo Developer