When running a massive job sometimes KNIME captures 90% and more of the CPU usage which then limits the performance of other programs and the display of operations in KNIME itself.
Is there an option to limit the use of all KNIME nodes to a certain % (like 70%) in order to have the system still working for other tasks and navigating KNIME WF. Otherwise the experience is that the system is slow.
This is more general operating system question. You can either set the priority of a process or pin it to certain CPUs. How exactly this works depends on the OS.
Since it looks you are using Windows, I believe you can change the process priority through the Task Manager.
