UE4 using more RAM after light build than before

Hi all,
i have run into a weird issue concerning the RAM usage of the UE4Editor process.

Build: 4.4.0-2237849

So here is what’s happening and i hope you can reproduce it this way:

  1. I start the editor and open my project. The process is using about 2 GB of ram.
  2. I click on Build Light Only and wait until it has finished.
  3. After that the Editor process itself is using about 6 GB of ram.
  4. Everytime i click on Build Light Only all this repeats and the ram usage is increased by another 2 GB.

Specs: i7 4790k, 32gb ram, gtx 680 and a freshly installed win7 64bit.

And here is a screenshot i made to visualize it a little bit better.

Is this a real bug or am i just doing something horribly wrong?

Hi Mirila,

Thank you for your report. I have entered in a bug report, TTP#344843 , to be assessed by our development staff. Have a great day!

Thank you for having a look.

I actually found an easy way to reproduce this issue.

  1. Create an empty Project and Map.
  2. Add a Stationary Directional Light and default size Lightmass Importance Volume.
  3. Create a Landscape with the following parameters.

5.Hit Build Lighting Only.