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Previous discussions: 2016: https://news.ycombinator.com/item?id=12166585 https://news.ycombinator.com/item?id=12166585 2018: https://news.ycombinator.com/ite

Previous discussions: 2016: https://news.ycombinator.com/item?id=12166585 https://news.ycombinator.com/item?id=12166585 2018: https://news.ycombinator.com/item?id=17280239 https://news.ycombinator.com/item?id=17280239 Community responses: - https://news.ycombinator.com/item?id=12216680 https://news.ycombinator.com/item?id=12216680 - https://news.ycombinator.com/item?id=12179222 https://news.ycombinator.com/item?id=12179222

chris_wot 6y ago
The response was: https://news.ycombinator.com/item?id=14222721 https://news.ycombinator.com/item?id=14222721
- asah 6y ago
  Even though 99.9% of applications will never run into Uber's issues, it's been 4 years and 4 major versions later, and I'd love to review these complaints and see if they still apply to PG 13.
  - Tostino 6y ago
    Wait until 14 for that comparison and it'll look much better. Bottom up index deletion helped solve some of the write amplification issues.
    - petergeoghegan 6y ago
      There is also index deduplication in Postgres 13 and the B-Tree enhancements in Postgres 12. All of these enhancements significantly improved the situation for workloads affected by what the blog post calls write amplification. (I myself call this phenomenon index version churn, since it is more descriptive and has less baggage.) I was the author of all of the above, including the Postgres 14 work you mentioned (though Anastasia Lubennikova was the primary author of index deduplication). To me it feels like one very large project -- the effects are cumulative, and each major Postgres version had B-Tree work that built on the last release in one way or another.
dang 6y ago
Thanks! Here's an annotated list of all those (plus chris_wot's and a couple others): Why Uber Engineering Switched from Postgres to MySQL (2016) - https://news.ycombinator.com/item?id=17280239 https://news.ycombinator.com/item?id=17280239 - June 2018 (47 comments) Re: Why Uber Engineering Switched from Postgres to MySQL - https://news.ycombinator.com/item?id=12179222 https://news.ycombinator.com/item?id=12179222 - July 2016 (67 comments) Why Uber Engineering Switched from Postgres to MySQL - https://news.ycombinator.com/item?id=12166585 https://news.ycombinator.com/item?id=12166585 - July 2016 (294 comments) Thoughts on Uber’s List of Postgres Limitations - https://news.ycombinator.com/item?id=12216680 https://news.ycombinator.com/item?id=12216680 - Aug 2016 (103 comments) A PostgreSQL response to Uber [pdf] - https://news.ycombinator.com/item?id=14222721 https://news.ycombinator.com/item?id=14222721 - April 2017 (82 comments) Why we lost Uber as a user - https://news.ycombinator.com/item?id=12201353 https://news.ycombinator.com/item?id=12201353 - Aug 2016 (285 comments) Uber's Move Away from PostgreSQL - https://news.ycombinator.com/item?id=12223216 https://news.ycombinator.com/item?id=12223216 - Aug 2016 (15 comments)

chris_wot 6y ago

The response was: https://news.ycombinator.com/item?id=14222721 https://news.ycombinator.com/item?id=14222721

asah 6y ago
Even though 99.9% of applications will never run into Uber's issues, it's been 4 years and 4 major versions later, and I'd love to review these complaints and see if they still apply to PG 13.
- Tostino 6y ago
  Wait until 14 for that comparison and it'll look much better. Bottom up index deletion helped solve some of the write amplification issues.
  - petergeoghegan 6y ago
    There is also index deduplication in Postgres 13 and the B-Tree enhancements in Postgres 12. All of these enhancements significantly improved the situation for workloads affected by what the blog post calls write amplification. (I myself call this phenomenon index version churn, since it is more descriptive and has less baggage.) I was the author of all of the above, including the Postgres 14 work you mentioned (though Anastasia Lubennikova was the primary author of index deduplication). To me it feels like one very large project -- the effects are cumulative, and each major Postgres version had B-Tree work that built on the last release in one way or another.

dang 6y ago

Thanks! Here's an annotated list of all those (plus chris_wot's and a couple others): Why Uber Engineering Switched from Postgres to MySQL (2016) - https://news.ycombinator.com/item?id=17280239 https://news.ycombinator.com/item?id=17280239 - June 2018 (47 comments) Re: Why Uber Engineering Switched from Postgres to MySQL - https://news.ycombinator.com/item?id=12179222 https://news.ycombinator.com/item?id=12179222 - July 2016 (67 comments) Why Uber Engineering Switched from Postgres to MySQL - https://news.ycombinator.com/item?id=12166585 https://news.ycombinator.com/item?id=12166585 - July 2016 (294 comments) Thoughts on Uber’s List of Postgres Limitations - https://news.ycombinator.com/item?id=12216680 https://news.ycombinator.com/item?id=12216680 - Aug 2016 (103 comments) A PostgreSQL response to Uber [pdf] - https://news.ycombinator.com/item?id=14222721 https://news.ycombinator.com/item?id=14222721 - April 2017 (82 comments) Why we lost Uber as a user - https://news.ycombinator.com/item?id=12201353 https://news.ycombinator.com/item?id=12201353 - Aug 2016 (285 comments) Uber's Move Away from PostgreSQL - https://news.ycombinator.com/item?id=12223216 https://news.ycombinator.com/item?id=12223216 - Aug 2016 (15 comments)