Scripting Engine Overhead: C++ Native vs Lua/C# Garbage Collection Spikes: Advanced Implementation and Real-World Architecture

[Matthew Edwards]

When I profile our competitive FPS during ranked sessions, even sub-millisecond GC stalls from the C# runtime show up as perceptible input lag and micro-stutters on 240Hz monitors.

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📍 Munich (Germany)

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[Ella Roberts]

Great topic. The core difference comes down to who controls memory reclamation. In a C++ native codebase you own the entire lifecycle—RAII, custom allocators, and arena/pool patterns mean allocations during gameplay frames are bounded and predictable, so your frame time stays flat. The trade-off is that you’re responsible for every leak and double-free.

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📍 New York, NY (USA)

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[Sam Roberts]

Real talk on this—GC spikes are exactly what kills your 1% lows, not average FPS. In C# (Unity’s managed runtime or IL2CPP with boxing), the culprit is almost always hidden heap allocations triggering the incremental GC. A single List growth, string concatenation in a hot path, or returning a new struct/array per frame will spike GC.

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📍 Seattle, WA (USA)

"144Hz is baseline, 360Hz is reflex, 540Hz is pure instinct."

[Matthew Edwards]

Followed the advice and finally killed the GC spikes—turns out my Lua scripts were allocating new tables every frame for event dispatch, and the C# side was doing the same with LINQ queries in the update loop. Switched to object pooling + pre-allocated buffer reuse, pinned the GC to manual mode during load screens, and moved the hot path to a native C++ module. Framedrops are completely gone now, running a rock-solid 60fps even with a hundred active scripts. Huge thanks to everyone for the pointers, this was driving me up a wall for weeks!

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[Chloe Richardson]

Real talk after testing this across a few titles: the GC spike problem is rarely about raw throughput—it’s about allocation timing. With Lua, the default incremental GC is fine for prototyping but will absolutely bite you in a competitive title where a 16ms hitch during a teamfight is a lost round. The fix I’ve landed on is treating the GC as first-class: run it in

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