XGBoost Tree Ensemble Learner - Serialized execution when starting two nodes?

Hi,

I’m using KNIME 5.5.1 on a MacBook M3 (iOS Sequoia 15.6).

Starting two XGBoot Tree Ensemble Learner (Analytics/Integrations/XGBoost) in parallel I observed, that one node is starting the boosting rounds, while the other node seems to wait at 5% with ‘Executing - performing node execution’ mouse-over msg.

What is the reason for this serialization?

Best

Erich