On Tue, 14 Jan 2025 at 04:05, Baodi Shi <ba...@apache.org> wrote: > > I believe that in the early stages of a major version, some breaking > changes are unavoidable. We can't ensure 100% prevention. > > However, once an issue arises, we need to fix and resolve it promptly, > rather than maintaining the breaking change. > > In other words, how many users are currently using version 4.0 in > production? We should aim to deliver future 4.0.x versions with high > stability and compatibility with version 3.0.
Thank you for raising these important considerations, Baodi. PR 9292 "Support large number of unack message store for cursor recovery" improvements deliver significant benefits for users running Pulsar at scale - which is a core use case for Pulsar. PR 9292 functionality should remain enabled by default. This helps keep Pulsar competitive in the high-scale data streaming space. To address your concerns, we can follow Enrico's suggestion to provide clear upgrade guide instructions for: - Handling upgrade and downgrade (rollback) scenarios - Disabling these features if needed While PR 23759 (https://github.com/apache/pulsar/pull/23759) enhances PR 9292's functionality and addresses issues, it shouldn't disable the "Support large number of unack message store for cursor recovery" functionality by default. This lets us continue advancing Pulsar's capabilities for high-scale deployments. -Lari
