Low utilization processor capacity

I'm using Knime server lite on a Windows server 2012 R2 based system with 4 Xeon processors with 4 cores each and 36 GB internal memory. The heap space in the ini file is configured on 16 GB yet.

I have a workflow with a loop with various parallel processes. Running this proces spends a lot of time. When I look at the task manager I see the utilization of the processors is only 15%. Memory is 12,7 GB. What opportunities do I have to speed up my proces?

Dear Taita,

it is difficult to diagnose without seeing the workflow. How big is the data?

Best, Iris