Andre, the answer is in this one-line comment by Brion:
https://bugzilla.wikimedia.org/show_bug.cgi?id=16614#c3
None of this bugs should be closed unless both the reported occurrence
and the underlying problem are fixed. The alternative is that it's
proved to be an occasional problem which won't repeat itself ("servers
were busy looking at hurricane Sandy clouds"), or that the bug is closed
LATER.
As for the noisy search results, the problem is
https://bugzilla.wikimedia.org/show_bug.cgi?id=39644 ;-)
Nemo