After updating my project from 4.18 to 4.19, I started getting huge FPS drops in regular intervals. I managed to trace back the issue to particle systems with mesh emitters and could reproduce the problem in an empty new project with a default particle mesh emitter (download link below). The FPS drops start out small, but get progressively worse the longer the editor is open. After a minute or two, “stat unitgraph” looks like this:
I couldn’t find any information about this behavior, so I have no idea if this is “by design” due to some new feature in 4.19 or if it’s a bug. Does anyone have any idea what’s going on there and how I can prevent or work around it? Should I simply report it as a bug and hope for a hotfix?
I tested the project linked above on a different machine today and didn’t run into any issues, so I assume it’s a hardware-specific bug. I’m working with a GeForce GTX970 (latest driver), the PC without the issue has a Radeon R9 200 Series. It would be great if someone could test the project and report whether or not it’s running smoothly.
As a point of reference, here’s a video of how it looks on my PC (you’ll have to skip through the video a bit to see the render time spikes increasing over time):
Another quick update: The problem also occurs with a GTX 1080, so I assume most or all Nvidia cards are affected. Although that’s hard to believe when apparently no one else seems to care about this issue.
