[nialo]

Do you know if this is still true with the newer "concurrent" garbage collector in more recent Mono versions? I work on an audio player app rather than games, but also have problems with the GC in Mono on IOS. We're hopeful that eventually they'll go away, but haven't tried again recently.

[thehardsphere]

I am not certain. Theoretically, it should be better, because I think they implemented a GC algorithm similar to the one on Windows. But I have never actually run it.

It's hard to emphasize how bad the Unity Mono GC is. It's a Mark-and-Sweep garbage collector, which is like the simplest-yet-least performant approach to GC there is. Nearly every other GC in production use in other stacks is better.

[danbolt]

I'm willing to bet that Mono GC has improved a lot, but I don't think that Unity frequently updates the runtime. It's kind of painful, from what I've been told.

[migueldeicaza]

We are collaborating with Unity to assist on upgrading not only their runtime but also to adopt the latest and greatest GC.

Additionally in C# 7, 7.1 and the upcoming 7.x series there are many improvements that reduce object allocation (like ref structs, value type tasks and others)

[atomicrat2552]

Unity is just now updating the runtime for the first time in seven years. I think only the 2017.x releases have the new Mono, and most platforms use their IL2CPP AoT compiler I believe

[littlehood]

It is an experimental option for Xamarin. Though haven't played with it.