What causes frame spikes from updating thousands of agents at once?

All agents run their expensive per-tick logic on the same frame, so the combined cost lands in a single update and blows the frame budget periodically.

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 Frame Spikes When Ticking Thousands of Sim Agents

Quick answer: Spread agent updates across multiple frames with a round-robin scheduler, processing a bounded slice each frame so per-frame cost stays flat.

A city sim that hitches every time the simulation ticks is doing all its agent work in one burst. The total cost is fine averaged out, but concentrating it on one frame causes a visible spike. Amortize the work by updating a fixed slice of agents per frame. Here is how to time-slice safely.

How to fix it

1. Round-robin a slice per frame

Keep an index into the agent array and update only budget agents per frame, advancing the index and wrapping around. Each agent still ticks regularly, but the cost is spread evenly.

2. Decouple decisions from movement

Run cheap per-frame work (movement, animation) every frame, but heavy decisions (re-pathing, job search) only on each agent's scheduled slice, so the visible behavior stays smooth while heavy work is amortized.

3. Budget by time, not just count

Track elapsed time within the frame and stop processing agents once you cross a millisecond budget, deferring the rest to next frame so an unexpectedly heavy agent cannot still cause a spike.

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.

Ship the fix, watch the signature disappear from the next build. That's how you know it's really gone.