Ankit, "I guess the SegmentInfo "minVersion" is the min across all segments during the merge process?" > That is correct
I am wondering if there is any way to end up in the 2nd scenario, without having deleted all the documents first? > Consider the following sequence of events... an index with 2 segments (seg1 and seg2) originally created in Lucene 8.x. ==> Upgrade to 9.x ==> index few documents and commit ==> seg3 gets created with version 9.x, but merge doesn't kick in ==> documents in seg1 and seg2 get deleted followed by commit.==> You are left with seg3 in 9.x but indexCreatedVersionMajor as 8.x ==> Upgrade to Lucene 10.x fails. -Rahul On Sat, Apr 19, 2025 at 1:01 PM Ankit Jain <jain.ank...@gmail.com> wrote: > Hi Rahul, > > Thanks for starting this interesting discussion. I was initially thinking > that this API potentially allows upgrading "indexCreatedVersionMajor" via > the merge process after rewriting all the segments, but I guess the > SegmentInfo "minVersion" is the min across all segments during the merge > process? > > So, I am wondering if there is any way to end up in the 2nd scenario, > without having deleted all the documents first? > > > Thanks > Ankit > > On Sat, Apr 19, 2025 at 9:17 AM Rahul Goswami <rahul196...@gmail.com> > wrote: > >> Hello, >> Today even after all documents in an index are deleted via an API call, >> reindexing still doesn't change the "indexCreatedVersionMajor" property >> value in SegmentInfos. Hence even after complete reindexing, an upgrade >> path X--> X+1 --> X+2 is still not possible as we end up with an >> IndexFormatTooOldException. >> >> Requesting an API (on IndexWriter?) which can reset this property (upon a >> new commit) to the current Lucene version if: >> 1) No more live docs present >> OR >> 2) If all SegmentInfo in the index have a "minVersion" AND "version" >> stamp of the latest version , but SegmentInfos has an older >> "indexCreatedVersionMajor". >> >> This will help users a LOT since they can now interact with the index >> purely via API without needing manual deletion and also help open up a >> legitimate path to upgrade when an index doesn't HAVE to be repopulated >> from the source. >> >> If there is agreement, I am happy to pick this up and submit a PR. >> >> Thanks, >> Rahul Goswami >> >> >>
