GPU particle performance in VR

Hello there,

I have a very strange issue with the performance of GPU particles. I have 2 effects I created. One created in an older version of UE4 (4.9) and one created in the current 4.10 version. It is a VR project.

The effect is basically the default particle but swtiched to GPU particles. Now here is the strange part. The particle created in 4.10 has a performance hit of about 2 MS when profiling. And the other does not. The 4.9 one doesn’t even have a particle simulation show up in the profiler. I have stripped down the effects to the very bare bones effect but the difference is still there.

Anyone have a clue why the migrated 4.9 effect doesn’t have a 2 MS performance hit. I would like to know what is causing the particle simulation time to be so extremely high. When viewing the scene with a normal camera, the particle simulation time is down to 0.02.

Anyone have any idea’s? Is this a bug perhaps?