2011/10/25 Harald Hoyer <harald.hoyer@xxxxxxxxx>: >> If anything, wouldn't it make more sense to move stuff in the opposite >> direction, from /usr/bin to /bin ? "usr" doesn't really mean anything >> - originally it was used because the filesystem format couldn't >> support more than 64MB(?) in a single volume, so the system had to be >> split to / and /usr. > > You want your OS in one directory and not split in 4 toplevel directories. I'd actually find it more natural to have _my data_ (whatever "data" means here, probably including httpd configuration and ssh keys - and defining this well is probably a difficult problem) in one directory and not all over / . I can rebuild "the system" anytime, and in a sense I don't really care about "the system", but I need to backup "my data". >> Also, Fedora already sort-of has a system for stateless OS images - >> see /etc/sysconfig/readonly-root. What will happen to it? > > It does not go away with this feature. Does it make sense to have two separate facilities for stateless OS images? How do they interact? When do I use one instead of the other? >> And more importantly, what is the overall benefit to our users? I >> can't find anything compelling in the "Benefit to Fedora" section (if >> /usr/ can be snapshotted, why not / ?); AFAICT this requires changing >> 257 packages for mostly aesthetic reasons. > > It's not only an aesthetic issue. This enables possibilities, which were > not doable before. > - snapshot /usr (with btrfs) If my stateful data were mounted to /var/lib/*, why couldn't I snapshot the read-only / volume just as easily? > - hot swap the OS (/usr) with another version Can I really do that when various processes will be running and have /usr/lib*/libc.so.* mapped? > - mount /usr ro and keep the rootfs writeable OK... but again, we supposedly have that functionality with /etc/sysconfig/readonly-root. > - share the _whole_ OS with other machines ... as long as I manage to update the configuration in /etc at the same time I update the OS image. Perhaps possible, but non-trivial. Mirek -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel