You are using a 4.4 kernel, which used the older delayed work stuff at sampling
rate. This has all changed a lot and we hooks paired with the scheduler now to
do this instead. Things have mostly changed since 4.7. Would it be possible for
you to use a later kernel and see if you still see something wrong?

I switched to the latest stable kernel available, 4.9.5. Judging from 
the first test I ran, using this kernel I cannot
reproduce this behavior anymore. Looks like it has been fixed by the 
changes introduced.

Now coming back to 4.4, the timers (in the delayed works) can't get delayed but
the work can as it is just another process.

Can you please describe how things changed from version 4.4 to 4.9 - I'm 
not sure if I understand correctly.
Before 4.7 the governor was just running as a kernel process and 
triggered by the (free running) timers and
now its hooked with the scheduler. So the scheduler ensures that the 
governor work is not delayed?!

But your setup has no almost load
and that seems unlikely as well. So, it looks to be a problem at some other
place. Tracers are your friend, only those can confirm something here.

Thanks for the tip with the tracers. If time allows I will have a look 
into that - I would like to know whats going
on, just out of curiosity.

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|  Philipp Miedl                                                   |
|  PhD Student @ Computer Engineering and Networks Laboratory      |
|  ETH Zurich, ETZG76, Gloriastrasse 35, 8092 Zurich, Switzerland  |
|  mail: philipp.miedl@ee.tik.ethz.ch      phone: +41 44 632 70 61 |
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