What causes RTS performance with large armies?

Each unit runs its own AI, pathfinding, and collision every frame, so hundreds of units overwhelm the CPU, especially during pathfinding and combat resolution.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix RTS Performance with Large Armies

Quick answer: Batch and time-slice unit AI, use group and flow-field pathfinding, and simplify distant or idle units so the army scales without per-unit cost dominating.

Large-army slowdown is per-unit cost multiplied. Batching and shared pathfinding fix it. Here is how.

How to fix it

1. Time-slice unit AI

Do not run every unit's full AI every frame. Update units in groups across frames and let idle units tick rarely, so the per-frame AI cost scales with what matters, not the total count.

2. Use group and flow-field pathfinding

Pathfinding each unit individually to the same destination is wasteful and causes clumping. Compute one flow field or group path many units follow, drastically cutting pathfinding cost for armies.

3. Simplify distant and idle units

Units far from the action or doing nothing do not need full simulation. Reduce their update rate and collision detail so the budget goes to units actively fighting.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Reproduce it once with full context and the fix writes itself. The hunt is the expensive part.