# \[Critical\] Extreme lag / performance problems on UEFN islands with creatures & wildlife while building enabled **URL:** \ **Category:** Issues and Bug Reporting\ **Tags:** fortnite-creative, unreal-editor-for-fortnite, fortnite\ **Created:** [January 3, 2024, 6:00pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206 "2024-01-03T18:00:49Z")\ **Posts on this page:** 10\ **Page:** 2
**Author:** ![chrisp\_games](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/chrisp_games/32/895155_2.png) [@chrisp\_games](https://forums.unrealengine.com/u/chrisp_games)\ **Post date:** [April 11, 2024, 5:37pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/21 "2024-04-11T17:37:45Z")
Little update: Bug still exists but got a few messages today of people having found different solutions. I optimized the map to be able to disable streaming completely which seems to have fixed the issue for now:) Obviously just a temporary fix as my map is an openworld map which needs the memory / streaming to be able to have more content 🙂 ---
**Author:** ![im\_a\_lama](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/im_a_lama/32/995063_2.png) [@im\_a\_lama](https://forums.unrealengine.com/u/im_a_lama)\ **Post date:** [April 11, 2024, 11:17pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/22 "2024-04-11T23:17:28Z")
This is a real issue that people are trying to solve by doing random things, this is clearly not our job and we clearly don’t have enough tools to debug that, could we get an expert telling us what’s wrong or if it’s even being looked at please ? ---
**Author:** ![im\_a\_lama](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/im_a_lama/32/995063_2.png) [@im\_a\_lama](https://forums.unrealengine.com/u/im_a_lama)\ **Post date:** [April 11, 2024, 11:27pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/23 "2024-04-11T23:27:39Z")
Do you have an ocean on your map btw ? (I think the infinite navmesh generated by it doesn’t help) ---
**Author:** ![CALINS\_GRATUITS](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/calins_gratuits/32/924222_2.png) [@CALINS\_GRATUITS](https://forums.unrealengine.com/u/CALINS_GRATUITS)\ **Post date:** [April 24, 2024, 1:37pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/24 "2024-04-24T13:37:28Z")
This issue should be fixed with 29.30. Navmesh is no more generated for the entire map but now uses Navigation Invokers around players, AI devices and NPCs. This is the new way to generate Navigation Mesh to support Open World and level streaming. Thanks. ---
**Author:** ![chrisp\_games](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/chrisp_games/32/895155_2.png) [@chrisp\_games](https://forums.unrealengine.com/u/chrisp_games)\ **Post date:** [April 29, 2024, 8:47am UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/25 "2024-04-29T08:47:42Z")
The bug is fixed! 🙂 ---
**Author:** ![chrisp\_games](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/chrisp_games/32/895155_2.png) [@chrisp\_games](https://forums.unrealengine.com/u/chrisp_games)\ **Post date:** [April 29, 2024, 8:51am UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/26 "2024-04-29T08:51:37Z")
Thank you so much for fixing the bug ! 🙂 ---
**Author:** ![im\_a\_lama](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/im_a_lama/32/995063_2.png) [@im\_a\_lama](https://forums.unrealengine.com/u/im_a_lama)\ **Post date:** [April 29, 2024, 10:31am UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/27 "2024-04-29T10:31:07Z")
Thanks for the update, though I find the explanation a bit weird, I’m pretty sure it was already like this when I tried a month ago, the navmesh would be generated upon spawning guards that had patrol enabled, which would cause lag spikes, meaning that the invokers were already used before So maybe the real thing happening is that it was previously being generated both at start and at runtime, which is weird too because the lag caused by patrolling guards would occur even on parts that are walkable by default (in which the navmesh could generate in edit mode) Now that I think about it maybe there was an incompatibility with World Streaming I’m glad that it fixed @chrisp_games issue, I still think navmeshes could use a better documentation and more tools to understand them better ---
**Author:** ![PledgedRanger](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/pledgedranger/32/1039255_2.png) [@PledgedRanger](https://forums.unrealengine.com/u/PledgedRanger)\ **Post date:** [May 10, 2024, 10:15pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/28 "2024-05-10T22:15:39Z")
Thank you for your help! Although it is 5/10/2024 and I got a Publishing rejection saying my map is not 30fps, and players reporting this. However when I test on my ps4 and pc it is running 100 fps on TSR Epic and Full Nanite settings turned all the way to EPIC. ps4 bounces 60fps to 120 fps. I am not sure what is causing lagging for other users and I gaurantee there is a bug. Please can you help? All my textures are 512 x 512 to 1024 x 1024 at the most! Please help ??? ---
**Author:** ![CALINS\_GRATUITS](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/calins_gratuits/32/924222_2.png) [@CALINS\_GRATUITS](https://forums.unrealengine.com/u/CALINS_GRATUITS)\ **Post date:** [May 22, 2024, 5:43pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/29 "2024-05-22T17:43:41Z")
Please create another post for your issue @PledgedRanger as it is unrelated to NPC. ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [August 27, 2024, 12:33pm UTC](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206/31 "2024-08-27T12:33:24Z")
hi @im_a_lama , The main documentation is [Understanding NPC Behaviors | Unreal Editor for Fortnite Documentation](https://dev.epicgames.com/documentation/en-us/uefn/understanding-npc-behaviors-in-unreal-editor-for-fortnite) The Colors in [What does the different colors of the debug navmesh mean?](https://forums.unrealengine.com/t/what-does-the-different-colors-of-the-debug-navmesh-mean/1301729/7) The main Documentation is in > **[AI and NPCs | Unreal Editor for Fortnite Documentation | Epic Developer...](https://dev.epicgames.com/documentation/en-us/uefn/ai-and-npcs-in-unreal-editor-for-fortnite)** > > Learn how to use NPCs and create custom AI logic and behaviors for your islands! [Previous page](https://forums.unrealengine.com/t/critical-extreme-lag-performance-problems-on-uefn-islands-with-creatures-wildlife-while-building-enabled/1585206.md?page=1)