Has anyone benchmarked Go's garbage collector lately? I like a lot of stuff about Go, but a lot of my work is in video games and real time audio, and I am extremely hesitant to use a garbage collected language for those things.
I've been working on a Go -> C++ compiler pretty much mainly for this use case, that skips the GC and concurrency stuff -- https://www.reddit.com/r/golang/comments/r2795t/i_wrote_a_si... -- Includes a demo video of a game I'm making with it and a built-in scene editor that uses reflection etc.
Repo for compiler itself: https://github.com/nikki93/gx (no README.md etc. yet, will be getting to that when I next have a chance (it's a side project)). It just takes around 1500 lines of Go thanks to the parser and typechecker in the standard library.
Go's perf was definitely non-trivially bad for me on WebAssembly.
> I know I can "do things to maybe cause the GC to run less" or such, but then that immediately starts to detract from the goal of having a language where I can focus on just the gameplay code.
Did you try implementing pooling (e.g. sync.Pool) for game objects/entities/components/etc? How did that go perf-wise?
I think the main thing is it starts to become a distraction from just writing the gameplay code. I don't have to implement the pooling stuff now that I have this compiler--naive / simple code tends to also start off with a high perf ceiling. But yeah if I did go further with the game in vanilla Go I might have to try the pool approach. Having worked on game engines with GC language runtimes (using Lua etc.) before, you always ultimately hit a perf ceiling due to lack of memory control and wish you could move out of it, but the runtimes don't give you a way to do that incrementally.
Ultimately in the game scenario the GC is actually just ... not helpful. Game logic code already explicitly handles lifetimes to some degree (eg. when this entity collides with that one, destroy it, etc.) -- emergently deciding when to free things based on references is usually not what you want. You do want it for resource management (like a texture cache), but it actually makes sense to kind of roll that on your own and adapt it to the game. So having a GC and then fighting it just sounds like an ill-fitted solution.
Allocation pooling gets around the Go GC but is also used in non-GC languages because it can drastically reduce the overall number of allocations AND improve cache performance. In a GC lang, it also forces you to be explicit with your lifetimes which can lead to better code (i.e. you need to Pool.Put rather than let the GC clean up).
In a well designed game engine, you will only need to implement it a handful of times (if that) to cover 99% of the hot code. Certainly not something to need to do for each class of game object.
Pooling is indeed what the ECS I use (entt) basically does--every component type has a contiguous pool of instances. Compiling Go to C++ lets me use entt among other things (target all of C++'s targets including Wasm, have some types of metaprogramming like statically reflecting all component types, etc.). The GC thing is just one of the results. There is no comparison for the amount of control you get vs. vanilla Go (where things can escape to the heap "whenever").
