On Wed, Apr 25, 2018 at 2:09 PM, Alexander Korotkov <a.korot...@postgrespro.ru> wrote: > Great. Thank you very much for your efforts on this feature!
You're welcome. I also appreciate the efforts of all Postgres Pro people. I especially appreciate Anastasia's work on this project. I hope that we see more B-Tree patches from Anastasia, and others. Getting this patch over the line was, it must be said, pretty painful for everyone. There were many reasons for that, some good, others not so good. However, I think that we've learned a few things about how to manage the risks around a patch like this one. This will hopefully make it significantly easier to do more work in this area. I think that it's badly needed. I think that its importance is generally underestimated, actually. The Gray and Reuter book says "B-Trees are by far the most important access path structure in database and file systems". I believe that that's just as true now, 25 years later. The core algorithms that are used by nbtree are generally very well implemented, and I don't think it's a good idea to work on features that change that. At least, I won't be working on something like merging of non-empty pages myself (or anything that touches concurrency, page deletion, etc). However, I do think that we can significantly improve nbtree for certain workloads by optimizing the representation at the page level, which I'm glad to see more interest in in the past few years. The major difficulty here is choosing an on-disk representation that lets us do everything that we'll want to do in the future. That requires strong cooperation. -- Peter Geoghegan
