Dennis Gustafsson – Parallelizing the physics solver – BSC 2025

Better Software Conference · 77K views · 2025 · 1:07:09

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Game programming & enginesSoftware performance & optimizationtalk

Why Hacker News recommends it

HN points to it as a practical example of solving a tricky multithreading problem, including using a spinlock to speed up a real-time physics solver.

What it is

Dennis Gustafsson, creator of Teardown, presents how he parallelized the physics solver for an upcoming game, followed by a Q&A. The talk was given at the Better Software Conference 2025.

Recommended by 2 HN commenters across 2 different months, 2025 to 2026.

What Hacker News said

Recommends fasterik · 2026-01 · on “Spinning around: Please don't – Common problems with spin locks”

As always: use standard libraries, profile, then write your own if the data indicates it's necessary. The following is an interesting talk where the author used a spinlock to speed up a real-time physics solver significantly. Dennis Gustafsson – Parallelizing the physics solver – BSC 2025 [this video]

Recommends Hikikomori · 2026-03 · on “The unlikely story of Teardown Multiplayer”

Not about multiplayer but still interesting. Dennis Gustafsson – Parallelizing the physics solver – BSC 2025 [this video]

Cites levodelellis · 2025-11 · on “Futurelock: A subtle risk in async Rust”

From my understanding this talk describes how he implemented a solution for a similar problem [this video] I'm saying if you're not writing multi-threaded code everyday, use a library. It can use atomics/locks but you shouldn't use it directly. If the library is designed well it'd be impossible to deadlock.