Icinga2 agent on Windows 2012R2 server consumes every bit of RAM

Hi everybody,

I installed the newest Icings2 agent (Icinga2-v2.11.3-x86_64.msi) on my fully patched Windows 2012R2 server (a virtual machine) and configured it as said by the documentation.
What happens ist, that the agent consumes all of the RAM available, leading to an unresponsive server. No RDP login possible, even the Veeam backup failed. As soon as I restart the Icinga2 service, the server comes back to live.
The eventlog of the server says
Windows hat diagnostiziert, dass der virtuelle Speicher unzureichend ist. Die folgenden Programme belegten den meisten virtuellen Speicher: icinga2.exe (3976) belegt 5746020352 Bytes, sqlservr.exe (1408) belegt 2410893312 Bytes und iisexpress.exe (4920) belegt 139886592 Bytes.
Source Resource-Exhaustion-Detector, Event ID 2004.

Has anybody encountered that before and how do I get rid of it?