Thanks Parveen, A community meetup demo would be very welcome I think!
Best, Jason On Sat, Feb 28, 2026 at 12:18 PM Parveen Saini <[email protected]> wrote: > > Hi all, > > While migrating a production system from Solr 5 to 8, we encountered subtle > ranking drift that did not surface in standard upgrade testing. The system > functioned correctly, but ranking behavior changed in non obvious ways. We > observed score distribution shifts, candidate set differences influenced by > negative score handling, and p99 latency regressions. > > Using that migration as a real world case, I put together a small side by > side validation harness designed to make behavioral differences across > major Solr versions observable. The goal is not to provide version specific > guidance, but to offer a structured approach for detecting ranking and > performance drift during major upgrades. > > The harness compares docset overlap, score distributions, and query level > behavior across versions. > > Sharing in case it is useful for others planning major Solr upgrades: > https://github.com/parveensaini/solr-lucene-migration-correctness > > Happy to share more details or present the approach at an upcoming > community meetup if there is interest. > > Thanks, > Parveen --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
