[$] Extending the mempolicy interface for heterogeneous systems

Non-uniform memory access (NUMA) systems are organized with their CPUsgrouped into nodes, each of which has memory attached to it. All memory inthe system is accessible from all CPUs, but memory attached to the localnode is faster. The kernel's memory-policy("mempolicy") interface allows threads to inform the kernel about howthey would like their memory placed to get the best performance. In recentyears, the NUMA concept has been extended to support the management ofdifferent types of memory in a system, pushing the limits of the mempolicysubsystem. In a remotely presented session at the 2024 Linux Storage,Filesystem, Memory Management, and BPF Summit, Gregory Price discussedthe ways in which the kernel's memory-policy support should evolve tohandle today's more-complex systems.