@leah wang The NiFi java process is actually two processes. The actual NiFi java process and a bootstrap java process. The bootstrap process has a very small memory footprint, 12MB to 24MB, that looks for the NiFi java process. If it doesn't find that process it will try to start it. The NiFi java process will reserve the memory allocated, in this case 8GB, and hold it. It doesn't actually use the memory, but reserves it so it is available as NiFi needs it. There won't be any garbage clean up until the memory usage is around 80% utilization. ... View more