[systemd-devel] fully volatile running from ram

[jr]

hello,

in a fully-volatile boot scenario /usr from a physical disk gets mounted on
top of an instance of a tmpfs. my first question is why is that necessary?
(the tmpfs part i mean)

my second question is, would it be possible to do the same but rather than
mounting the /usr *populate* the said tmpfs with OS tree from said physical
disk, preferably in a blocked or fs cached setup (db-cache or bcachefs). i
realise that this can be done easily in initrd or even initramfs can hold
the /usr but the problem there is when we boot "developmen" and not
"production" in which case we want updates to be written to disk.

jrun