Where do the performance cliffs come from? | POSETTE 2024

From the creator

Video of a conference talk about where do performance cliffs come from presented by Tomas Vondra at POSETTE: An Event for Postgres 2024. When running queries on a Postgres database, chances are you have experience with hitting a "performance cliff" - an abrupt change of performance for a given Postgres query, after only a small change in data and/or query parameters. In this talk, you'll learn why performance cliffs happen in Postgres. After a brief explanation of how cost-based optimizers work and what assumptions that relies on, I'll show a couple examples why/how it fails. I'll also share recommendations on how to mitigate these issues. If time permits, I'll talk about a couple interesting improvements & possible solutions proposed in recent research projects, focused on making Postgres query execution more adaptive & robust. Tomas is a long-term PostgreSQL contributor & committer, focusing on performance, query planning & optimization, etc. Chapters: 00:00 Introduction 01:27 What is a performance cliff? 09:03 Runtime decisions 14:21 Multiple Paths 19:12 Mitigations 24:06 Robustness / Research papers 📕 Everything you need to know about POSETTE: An Event for Postgres 2024 can be found at: https://aka.ms/posette ✅ Learn more: Watch more POSETTE talks: https://aka.ms/posette-playlist-2024 📌 Let’s connect: X – @PosetteConf https://x.com/PosetteConf Mastodon - @posetteconf https://mastodon.social/@posetteconf Threads – @posetteconf https://www.threads.net/@posettecon

Published 2024-06-13 · Watch on YouTube ↗
Availability and playback restrictions are controlled by the original channel.