Updates to nonvolatile memory pages are mirrored so that certain features of a computer system, such as live migration of applications, fault tolerance, and high availability, will be available even when nonvolatile memory is local to the computer system. Mirroring may be carried out when a cache flush instruction is executed to flush contents of the cache into nonvolatile memory. In addition, mirroring may be carried out asynchronously with respect to execution of the cache flush instruction by retrieving content that is to be mirrored from the nonvolatile memory using memory addresses of the nonvolatile memory corresponding to target memory addresses of the cache flush instruction.