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Comment by vladharbuz | Hacker News Reader

Hey, I'm open to any answer that helps me write better programs. :) Which languages do you have experience working with in high-performance situations? I, for one, had high hopes for using Go for video game development, but it turns out that even in highly-tuned Go code with the latest GC optimisations, there are still significant GC pauses that cannot be overcome [0]. However, perhaps you're referring to other types of GCs I'm not aware of?

[0]: https://ebiten.org/blog/native_compiling_for_nintendo_switch...

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I don’t have much experience with C#, but currently that seems to have the best balance of control over allocations and a performant GC due to having value types (and pointers as well if I’m not mistaken?)

But regarding GC, Java is unquestionably the king in that aspect, throughput-wise G1 is unbeatable and its relatively new ZGC might be of interest to use. It is the one I thought about previously, it currently promises sub-millisecond max pause times and this pause time doesn’t grow with heap size. Unfortunately Java doesn’t have value types yet, so you either write your hot loops with only primitives and allocations you make sure gets optimized by the escape-analyser, or do some manual memory management with the new Panama APIs, which are quite friendly in my opinion.

EDIT: Just read your link, while Java can be AOT-compiled with GraalVM, only the enterprise version supports some of the more exotic GC-variants (though not sure about ZGC). It should be free for personal use, but do have a look at it. Though what I wrote concern mostly running code with the JVM.

Yep, worth noting that there are a number of actual games that use MonoGame / FNA, including low-latency platformers like Celeste. I've actually found games written in these engines to be among the best performing games all around on old hardware.

Java's ZGC as of jdk 17 has very low pause times (e.g. a p99 of roughly 0.1 ms in this benchmark[0]). Their stated goal is to remain sub 1 ms, but in practice it stays well below that.

The JVM isn't the most common game dev platform, but I have been enjoying using LibGDX with Scala on jdk 17 with ZGC.

[0] https://kstefanj.github.io/2021/11/24/gc-progress-8-17.html

I use pony https://ponylang.io/ as a language - it's an Actor based language with GC where every actor has its own memory and is responsible for its own GC.

The main feature is its ability to safely share or move data around between actors in a way that is data-race and deadlock free. Pony doesn't use locks anyways :-)

A high level as to how it achieves this:

i. All variables have a "reference capability" - which is a description of what you can and cannot do with the variable alias (pointer) you have.

ii. The references to the data (think pointer) are passed in messages.

iii. As references are made and removed, actors send messages to the originating actor updating the count of references. When the count reaches zero, that data can be GC'd.

It's nice, because unlike some other language runtimes, it doesn't have to stop the world to work out what can and can't be GC'd. It's all done on-the-fly as it were.

Hi, this article says that I could overcome GC pauses. Thanks.

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