If you run a system with an AMD CPU, you might want to hold off upgrading to Windows 11 for a bit.
AMD has announced that all of its WIndows 11-compatible processors can suffer from reduced performance in some applications when used with the new operating system, with extreme outliers in eSports gaming titles resulting in up to a 10-15% reduction. For applications, AMD says that the performance impact weighs in at 3–5%. A software update and a Windows Update are in the works to address the issues, with both expected to arrive in October 2021 (this month).