Hi, When I checked the Unity 2017.3.0f2 release notes, I found some improvement in cloth physics. So I did a quick test and found out the cloth physics is broken in Unity 2017.3.0f2. In my test scene, the performance in Unity 5.5 is about 8.0ms. But the performance in Unity 2017.3 is about 680ms! I also notice the verts count is 161k which should be 45k in Unity 5.5 I just put one dress(40020 verts) in the scene and add cloth component to this object. Finally, I paint the verts on top of the dress to fix this mesh. Very simple.