Strange performance problem, profiler not helpful

Hello,

We are very confused right now by this impressive performance dip we are getting. Without going in too much detail, this is suppose to be game on rail, so everything is mostly happening the same way every time we play, but this lag is happening somewhat randomly between one and two minutes into the game.

We tried finding the culprit for a while, but without success and the profiler isn’t being much of a help, but we are not very familiar with it, so if anyone is able to see the problem it would be very appreciated. All the thread, even the game thread, seems to be stalled except for the render thread which is spending his time with multiple “New Bound Shader State Time”

Any help would be greatly appreciated.

Thank you !

Well, we tried to delete absolutely everything from the scene except for the camera in the sequencer and a sky dome to be able to see something on the screen and we still get this huge spike happening, dropping from 270 fps to less than 100. So if anyone has even a hint for us we would be very grateful.