Do you use D's GC?

[Dylan Graham]

On Sunday, 1 August 2021 at 08:54:05 UTC, Kirill wrote:
> It's interesting to hear do you use D's GC? Or do you use your 
> own custom memory management structure?

It entirely depends on the scope of the problem. For a script or 
tool, absolutely yes. Game development? Yes. Embedded? Maybe.

I implemented a voxel game (similar to [Blockscape around 
2012](https://images.app.goo.gl/7yJAfnUu9wa7A74fA)) and the GC 
was largely not a problem. The underlying array for a chunk of 
voxels (chunks come in and out of scope very frequently as the 
player moves), was `malloc`ed to reduce pressure on the GC (and 
to enable on-the-fly RLE compression). Otherwise, everything else 
was GC dependent and I did not have performance problems.

> How performant is GC?

Some people complain about it, but I haven't had an issue. I 
think my usage of it was before they introduced the 
parallel-sweep GC. I don't recall GC pauses any longer than 
4-5ms, and there was no stutter.

D's GC is significantly easier to manage than something like 
C#'s. I ported the game over from C# because I was always 
fighting .NET's GC. It always seemed to run, no matter how much I 
tried to stop allocations (while you can can *temporarily* stop 
the GC, it wasn't a solution). D's GC only runs *when you 
allocate with* `new`.

> The reason I'm asking is I'm planning to dive into 3D game dev 
> with D as a hobby in an attempt to create a game I dreamed of 
> since I was a kid. I'd like to know if GC is worth using at 
> all, or should I go with 100% manual memory management.
>
> Any opinion is appreciated. Thanks in advance.

We might be able to give a more informed answer with some of your 
planned technical details. As is, I'd advise you use the GC.

D is in a very good position to become a gamedev language. The GC 
is very helpful, but when you really need, it's super easy to opt 
out. D is about giving *you* power.