Got a Java process with about 4 GB memory consumption after just starting up macOS
Yes, Allan's solution in his comment

Issue the command sudo launchctl list | grep 458 This will list the service associated with that process ID. Note that the PID may change, so check activity monitor for the PID number before issuing the command.

worked very well (In this case as the rogue process was run as the current user this worked without &quot;sudo&quot; also).
For me also it is Cassandra which is consuming the memory.