@Jarinek Some infofmation about your nifi configuration will help be more accurate. For example: min/max ram, number of cores, disk configuration, etc.. Information about your flow is important too. The processor/queue back pressure, concurrency, and run time all effect the performance you need.
Without this information, it sounds like your testing solution is exceeding the inbound capabilities of the flow tuning (nifi config, processor/queue config). You should look to increase concurrency, increase queue size and back pressure based on # of flowfiles moving through. your data flow. You should also inspect the min/max thread counts as these have a major impact on performance. All of these items will be seriously limited with a single node, so be mindful of your expectations.
If you can I would recommend a small 3 node nifi cluster to evaluate nifi performance in a better test environment where you can really turn up the performance and distribute the work load across 3 nodes. With 3 times as many cores & ram you can make better use of min/max thread count, increase concurrency much higher, and you should see the stability you are expecting.
If this answer resolves your issue or allows you to move forward, please choose to ACCEPT this solution and close this topic. If you have further dialogue on this topic please comment here or feel free to private message me. If you have new questions related to your Use Case please create separate topic and feel free to tag me in your post.
Thanks,
Steven @ DFHZ
