[$] Kernel-text replication on NUMA systems

Kernel developers often go out of their way to reduce the memory used by
the kernel itself; that memory is not available for the workloads that
people are actually interested in running on their systems. Lower memory
usage also tends to lead to better performance overall. But there are
times when the expenditure of some extra memory can make the system faster.
The replication of the kernel's text (executable code) and read-only data
across a NUMA system may be a case in point; patch sets have been posted
adding that capability to two architectures.