Kernel code synthesis reduces the execution path for frequently used kernel calls.
Optimistic synchronization increases concurrency within the kernel.
Their combination results in significant performance improvement over traditional operating system implementations. As with access to immutable data, the details of the mechanism can be hidden with a surrogate object. A General Approach for Run-Time . . . Henry Massalin and Calton Pu. The kernel of a multiprocessing operating system - Wulf, Cohen, Corwin et al.