Hi Peter, Thanks for initiating this discussion. Despite activity on other branches, I have also observed the lack of recent releases for Xodus. I have not encountered the issues described in NIFI-12468, but I agree that an alternative needs to be considered based on the lack of maintenance activity. It is interesting that Xodus now mentions future work on YouTrackDB, but that repository has not published a release to Maven Central, so it does not appear to be in a helpful position.
Anything that requires a native library and wrapper is not a great candidate, like RocksDB as you noted. I looked at MapDB recently as well, but I was also concerned about the maintenance level. I'm not familiar with Chronicle-Map, so I plan to take a closer look. It appears to have a number of dependencies, which is initially concerning. Returning to H2 is not a good option, but mentioning it for the sake of background. Apache Derby is another embedded database, but it has had less maintenance in recent years. I plan to evaluate options and follow up, thanks again for raising the topic! Regards, David Handermann On Fri, Sep 19, 2025 at 7:46 AM Peter Gyori <[email protected]> wrote: > > Team, > > I am writing to propose we replace Xodus ( > https://github.com/JetBrains/xodus ) in NiFi with a more actively > maintained library. This change is necessary due to two key issues: > > - The Xodus project is no longer under active development. > - We've encountered issues with Xodus when running NiFi on Java 21, as > detailed in the comments of > https://issues.apache.org/jira/browse/NIFI-12468 > > I have evaluated some potential replacements and have summarized my initial > findings below. > > Replacement Candidates: > > - RocksDB https://github.com/facebook/rocksdb > - Pros: Popular, actively maintained, and license-compatible. > - Con: Written in C++ and relies on JNI. > - MapDB https://github.com/jankotek/mapdb > - Pros: Java-based and license-compatible. > - Con: The last release was in January 2024. > - Chronicle-Map https://github.com/OpenHFT/Chronicle-Map > - Pros: Java-based, actively maintained, and license-compatible. > > I welcome your input on this proposal, these candidates or any other > alternatives you might suggest. > > Regards, > Peter
