Highlights of FOSDEM 2023

Of the talks I attended at FOSDEM ‘23 and FOSDEM PgDay ‘23, these were the ones I thought were particularly interesting or informative.

Understanding PostgreSQL Query Plans (Stephen Frost)

A comprehensive overview of the various options to EXPLAIN available in PostgreSQL with explanations for how to interpret query plans. Also dipped into some details of how Postgres calculates cost values internally.
FOSDEM PgDay wasn’t recorded but a previous version of the talk is available here.

Fighting write amplification by stimulating HOT updates through the fill factor (Derk van Veen)

An explanation of the different ways Postgres can update records, the benefits of Heap-Only Tuple (HOT) updates and examination of how tuning the fillfactor table setting can improve the proportion of updates that can be applied as HOT updates. Also covers how to monitor proportion of HOT updates and circumstances that will prevent HOT updates from occurring.
A previous version of the talk is available here. There is also a series of blog posts by the speaker covering the content of the talk here and here.

Chimera Linux (Daniel Kolesa)

A new Linux distro utilising FreeBSD userspace tools and LLVM. Lots of thought seems to have gone into design decisions. Video and slides here.

Exploring WebAssembly with Forth (Remko Tronçon)

A Forth compiler hand written in web assembly. Video and slides here.

Whippet: A new production embeddable garbage collector (Andy Wingo)

A discussion of technical details of a new garbage collector for Guile. Video and slides here.

Algebraic Effects and Types as First-Class Features in the Fuzion Language (Fridtjof Siebert)

An explanation and demonstration of the algebraic effect system in Fuzion language. Video and slides here.

IDP-Z3, a reasoning engine for FO(.) (Pierre Carbonnelle)

An overview of the IDP-Z3 reasoning engine. Video and slides here.

The Microkernel Landscape in 2023 (Martin Děcký)

Overview of various microkernel projects that are in active development today. Video and slides here.

NOVA Microhypervisor Feature Update (Udo Steinberg)

An overview of the Nova microkernel followed by discussion of recent improvements. The coverage of recent CPU protection features went into some depth, including measured performance impact.
CPU features covered were:

Video and slides here.