mosermw commented on PR #10372: URL: https://github.com/apache/nifi/pull/10372#issuecomment-3366534034
For -XX:+UseStringDeduplication, I guess it's anecdotal story time. We had a heavily loaded cluster that experienced a sluggish UI and sometimes the UI would completely stop responding. Also, the nodes would often drop from the cluster. We traced this to excessive garbage collection and stop-the-world time. It used G1GC and was doing full gc every 10 seconds with 5 seconds of stop-the-world. Once we applied the UseStringDeduplication flag, we saw a 50% reduction in full gc events with stop-the-world times in milliseconds. This made the UI happy and cluster nodes stopped dropping out. Of course, every NiFi flow is different, so it's not predictable how much this can help in general cases. We had some NiFi clusters that never do a full gc. Our prevailing theory was this cluster dealt with a hundreds of flowfile attributes on every file, which of course are all Strings. It also had custom components that also dealt with a lot of Strings while processing each file. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
