On 6/2/2016 7:04 AM, Lennart Poettering wrote:
In all of these cases you really want to make sure that whatever the
user did ends – really ends – by the time he logs out.
I apologize if this has already been brought up, but I didn't see this
particular point raised in the replies I've read and I wanted to be sure
it is mentioned.
The potential problem I see with changing the default behavior of
systemd is that it is non-intuitive and could be potentially harmful if
the user is not aware of it. Consider the following example. I
routinely use screen when I connect to the systems I manage remotely
specifically when I try to apply updates. I do this because if my VPN
connection or my Internet connection is interrupted, the update process
will not die with my login session. Incidentally, I learned to use
screen when applying updates the hard way many years ago when a killed
update wreaked havoc with a system of mine and I found screen to be an
Currently screen is a utility whose purpose is, in part, to allow a user
to disconnect from a running process in a safe way that will allow it to
keep running and be resumed in the future from another session
entirely. Now that will only be valid if the user knows whether or not
systemd is configured on the system in question to not automatically
reap these kinds of processes. This would have the effect of
transforming what is clear and precise documentation of a well known and
widely used utility into something that relies on another set of system
configuration settings that are arguably not as intuitive.
For the record, I am not trying to say I am opposed to increasing system
security and progress in general in the slightest - both are laudable
goals. What I am trying to say is that there is a lot of merit in
making sure things are not made unnecessarily more complex and difficult
to discern unnecessarily. Whatever needs to be done to increase
security needs to be done while embracing the notion of not pulling the
rug out from under legitimate uses of programs whose indiscriminate and
unexpected reaping could cause disastrous results.