[systemd-devel] question on special configuration case

[Lennart Poettering]

On Tue, 07.06.16 21:00, Greg KH (gregkh at linuxfoundation.org) wrote:

> On Wed, Jun 08, 2016 at 02:04:48AM +0000, Hebenstreit, Michael wrote:
> > > What processes are showing up in your count?  Perhaps it's just a
> > > bug that needs to be fixed.
> > /bin/dbus-daemon
> > /usr/lib/systemd/systemd-journald
> > /usr/lib/systemd/systemd-logind
> > 
> > I understand from the previous mails those are necessary to make
> > systemd work - but here they are doing nothing more than talking to
> > each other!
> 
> Really?  No journal messages are getting created at all?  No users
> logging in/out?  What does strace show on those processes?

It's the "watchdog" logic most likely. i.e. systemd has a per-service
setting WatchdogSec=. If that's set the daemons have to ping back PID
1 in regular intervals, or otherwise are assumed hanging.

On top of that PID 1 actually talks to hw watchdogs, if there are any,
by default.

If both of that is turned off, then there should be zero wakeups
really...

Lennart

-- 
Lennart Poettering, Red Hat