On Thu, 14 Jun 2018 21:02:51 +0200
Daniel Wagner [off-list ref] wrote:

I am not sure if I am hunting a ghost. During testing on the CI
testfarm, a spike of around 400us popped up on a x86_64 box
(*). Fortunately, I have the same CPU for testing at home and I
tried very hard to reproduce it. Even Steven was helping out for
setting up the test correctly. But so far I haven't seen it again.

I believe it was a ghost. I just scared it away when I came over ;-)

-- Steve