KDevelop 5 too slow?

Hi,

I migrated from KDevelop 4 to 5 a few days ago (git master).
The first thing I noticed is that even for a very simple Qt5-based
project, KDevelop needs 2-3sec (or more) to auto-complete, which
is very slow compared to KDevelop 4. Actually, after simply modifying
any line it takes quite some time (sometimes over 5 seconds) for
the changes to get picked up and the error squiggles to go away.
All this on a quite fast machine (i7-2600 desktop).

Is this normal behavior, or is my build broken somehow?

KDev* release build from 2017-04-22 git master.
OpenSUSE 42.2, kde 5.9.4, clang 4.0.0, qt 5.8.0, gcc 4.8.5.
i7-2600, 16 GB RAM, SSD.

Thanks,
Alexander