long running sessions, restarts, etc.

[David Malcolm]

On Tue, 2009-09-29 at 14:12 -0400, Bill Nottingham wrote:
> With the move to more mobile devices (laptops, etc.), we're more likely to
> have very long-running sessions that are just suspended and resumed, as
> opposed to a workstation that is logged out every day.
> 
> This means that for me on rawhide, my session is often much longer-lived than my
> software set, as I'll have a two-week session that is running older code
> that I've long since upgraded past. Even for those on an actual release,
> this can be an issue given our update stream.
> 
> For system-level services, we have the idea of try-restart on upgrades; if
> the service is running, we automatically restart it on upgrade. How can
> we implement this sanely for session/desktop services? For example, in
> my session I see:
> 
> gvfsd
> obex-client/obex-data-server
> evolution-data-server
> packagekitd
> notification-daemon
> any number of status icons (volume control, gpk, g-p-m, etc.)
> ... and more I'm forgetting ...
> 
> Since very few of these have state, can't we implement a framework where
> they automatically get restarted on upgrade?

Brainstorming: perhaps when rpm updates/deletes a file it could look at
what processes are mapping that file (in particular ELF files), and thus
build a list for a transaction of all PIDs that now have stale data
(e.g. using old versions of a .so file that now has a security fix in
the new on-disk version).

No idea how to pass this information up through yum/PackageKit in a
useful way though.

Hope this is helpful
Dave