The move away from kernel extensions in favor of native virtualization code has helped deliver useful performance improvements.
“Parallels invested more than 25-man-years of engineer programming to take full advantage of the new macOS Big Sur architecture and revamped kernel extensions to deliver our best Windows-on-Mac performance ever for our Parallels Desktop 16 customers,” said Nick Dobrovolskiy, Parallels Senior Vice President of Engineering and Support in a statement. As a result of the abandonment of such extensions on the Mac, the company had to dedicate a great deal of energy to replace them with native Mac virtualization code.
One major change in Big Sur is the removal of support for third-party kernel extensions (kexts), which is what Parallels relied on for its emulation.
