If left idle, UEFN starts losing fps

Summary

Noticed that after leaving UEFN idle for a while (with live edit on), and come back after, the viewport moving camera will start consistently have lower fps

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Stability

Steps to Reproduce

Open UEFN with a project at 50k memory
Open live edit
Leave it idle for an hour

Expected Result

UEFN fps will not drop

Observed Result

UEFN fps drops depending the time its left idle (gets worse over time)

Platform(s)

pc

Hi,

Can you please check the memory usage for the editor process in task manager (Details tab) before and after the idle period? The “Memory (private working set)” and “Commit size” columns are both relevant. Do they increase significantly?

I found the cause (it was a niagara particle), but when I checked memory it wasn’t on any values that I havent seen before (seen way worse before on this pc). Sorry if this doesnt help, I have the particle uasset file if you want me to send through DevRel (strange thing is that the effect is based on one of the templates inside niagara, which is why I didn’t think of it initially)

FORT-1129152 has been added to our ‘To Do’ list. Someone’s been assigned this task.

Can you please attach the particle system? (or send through DevRel)