# 4.12 bad performance **URL:** \ **Category:** World Creation\ **Tags:** unreal-engine, Performance, bug-report, editor, UE4, question\ **Created:** [June 2, 2016, 7:01pm UTC](https://forums.unrealengine.com/t/4-12-bad-performance/359411 "2016-06-02T19:01:42Z")\ **Posts on this page:** 1\ **Showing post:** 9
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [June 3, 2016, 1:44pm UTC](https://forums.unrealengine.com/t/4-12-bad-performance/359411/9 "2016-06-03T13:44:43Z")
Are you streaming levels or do you have all levels constantly loaded? Are you using the world composition browser? Have you made sure all levels have had lighting built and saved or just the persistent level? Additionally, have you run through our lighting and swarm agent troubleshooting guides to see if they resolve your error? > **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)** > > After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — https://unrealcommunity.wiki/! You will be able to find content from... > **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)** > > After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — https://unrealcommunity.wiki/! You will be able to find content from... --- _[View the full topic](https://forums.unrealengine.com/t/4-12-bad-performance/359411)._