Congrats, that is a substantial nifi cluster.   Before other collaborators get into comment, we still want some more details.  @MattWho can probably help better than I can.  Let's make sure he has more than enough context.   Few more questions:   Can you describe your disk arrangement? Can you share your Thread Count settings (reference link in my previous reply)? What are the nifi min/max memory settings? Can you comment on any additional steps you have taken from known NiFI Performance Tuning?   https://community.cloudera.com/t5/Community-Articles/HDF-NIFI-Best-practices-for-setting-up-a-high-performance/ta-p/244999   ... View more