Lua Memory That Stops Surprising You

Tue, 07 Apr 2026 09:00:00 -0600

With my current projects, I’m spending a lot of time in Lua 5.4. Get ready for some posts about it as the good, bad, and ugly has been an interesing journey–not just in the language, but in how the language has modernized in the last few releases.

Let’s start with something that I could nearly ignore in C# and javascript: garbage collection.

Lua’s garbage collector doesn’t announce itself. It waits until the heap crosses a threshold, then pauses execution while it sweeps. In a local system or editor, that pause is invisible. In a game running at 60 frames per second, a 16ms budget per frame means any GC pause over a few milliseconds shows up as a hitch the player feels. Worse is server side code and that 16ms hits hundreds of clients at once.

Memory-Optimization on David R. Longnecker - Converting Coffee to Code

Lua Memory That Stops Surprising You