This version introduced more aggressive memory ballooning. Disable it globally: System > Preferences > QEMU > Disable Memory Ballooning (Check) > Save .

The system requirements for PNetLab 5.3.11 may include:

Elias clicked the 'Start' button on his topology. The little green lights flickered on the virtual IOL switches. Then, the lights turned red. The CPU usage on the host server spiked to 100% and stayed there. The WebUI froze.

3.11 release. Deep Dive into PNetLab 5.3.11: The Go-To Network Emulation Platform Just Got Faster