# Large frame spike caused by Chaos physics broadphase rebuild during World Partition streaming **URL:** \ **Category:** Programming & Scripting\ **Tags:** Optimization, fps-drop, unreal-engine, WorldPartition, Blueprint, question\ **Created:** [March 13, 2026, 2:07am UTC](https://forums.unrealengine.com/t/large-frame-spike-caused-by-chaos-physics-broadphase-rebuild-during-world-partition-streaming/2705818 "2026-03-13T02:07:20Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![BioFrost.in](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@BioFrost.in](https://forums.unrealengine.com/u/BioFrost.in)\ **Post date:** [March 13, 2026, 2:07am UTC](https://forums.unrealengine.com/t/large-frame-spike-caused-by-chaos-physics-broadphase-rebuild-during-world-partition-streaming/2705818/1 "2026-03-13T02:07:20Z")
![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/0/e/e/0ee5f17e39a59fa82b8456b5925efafbe2111375.png) Hi everyone, I’m trying to track down a large frame spike in my project and I would appreciate any insight into what might be causing it and how to mitigate it. The game is an open-world project using **World Partition**. The issue only happens while the player is **moving** , which makes me suspect that it is related to streaming. This step alone takes around **85–90 ms** in a single frame. From what I understand, this seems to be a **Chaos physics broadphase / spatial acceleration structure rebuild**. Earlier in the same frame I also see: - `UpdateLevelStreaming` - `AddToWorld` - `RegisterComponent` - `FoliageInstancedStaticMeshComponent` - physics bodies being initialized 1. Is there a recommended way to **prevent Chaos from rebuilding the spatial acceleration structure so expensively** during streaming? 2. Are there best practices for **foliage / instanced meshes with collision in large World Partition worlds** to avoid this?