Thank you, David and Matt. I will also evaluate QuestDB to see if it's a good fit.
Regards, Peter On Fri, Sep 19, 2025 at 7:04 PM Matt Burgess <mattyb...@apache.org> wrote: > That's where I'm tending towards as well, QuestDB. I think it's a good idea > to back whatever appropriate capabilities with the same database library if > only just for maintenance purposes. Of course the downside is any > vulnerabilities that may arise, such as we had to deal with re: H2 a couple > years ago. > > Regards, > Matt > > On Fri, Sep 19, 2025 at 11:34 AM David Handermann < > exceptionfact...@apache.org> wrote: > > > Hi Peter, > > > > Another option I am evaluating is QuestDB [1]. There is an optional > > framework extension that uses QuestDB for persistent Status History. I > > would not intend to couple or reuse code from that module, but > > building a new implementation of the Audit Store on QuestDB might be a > > good solution. The Flow Configuration History is certainly > > timestamp-oriented, so this might be a potential way forward. > > > > Regards, > > David Handermann > > > > [1] https://questdb.com > > > > On Fri, Sep 19, 2025 at 9:36 AM Peter Gyori <pgy...@apache.org> wrote: > > > > > > Hi David, > > > > > > Thank you for your reply. > > > > > > Regarding NIFI-12468: whenever an Xodus transaction exceeds 60 seconds, > > the > > > database connection is terminated, and NiFi does not recover without a > > > restart. (Interestingly, with NiFi-1.x using Java11, recovery is not an > > > issue.) > > > > > > I also evaluated YouTrackDB, but ultimately decided against it. As an > > > object-oriented graph database, YouTrackDB seems to be a more > high-level > > > and complex solution than the simple key-value datastore we are looking > > for. > > > > > > Regards, > > > Peter > > > > > > On Fri, Sep 19, 2025 at 3:19 PM David Handermann < > > > exceptionfact...@apache.org> wrote: > > > > > > > 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 <pgy...@apache.org> > 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 > > > > > > >
