I am noticing something really odd with Blender 2.8 viewports. I often get quite poor viewport performance with very visible lag and microstutter when I launch Blender after freshly rebooted computer with nothing else open. As soon as I open anything that at least little bit utilized the GPU, such as having running OBS screen recorder in the background, Blender is perfectly smooth. But it appears that Blender itself is not capable of utilizing my GTX1080Ti on Windows well enough so that it doesn’t keep going idle.
Another big issue is that as soon as viewport manipulator is shown, I get significant input lag in the viewport. This is apparently caused by Vsync. If I force Vsync off in the nVidia drivers, the input lag and input delay with manipulator shown is completely gone.
Since Windows 10 is by far the most popular platform of Blender users and nVidia cards are the most popular brands, it would be very appropriate to thoroughly test these performance corner cases on Windows, instead of constantly developing Blender 2.8 in the dark on a platform only fraction of users will use. These Windows specific issues really tend to add up.
I am sure by now most of the developers are aware how important first impression is, so it’s desirable that Blender 2.8 performance on Windows is good out of the box, without requiring users to manually set up obscure setting combinations in nVidia driver.