[$] Improving access to physically contiguous memory

For years, kernel developers have been told to avoid allocating large chunks ofphysically contiguous memory; as the system runs and memory becomesfragmented, satisfying such allocations becomes increasingly difficult.But, as Zi Yan pointed out in a memory-management track session at the 2019Linux Storage, Filesystem, and Memory-Management Summit, there are timeswhen contiguous memory is useful. In this session, the memory-managementdevelopers discussed ways to make such allocations more likely to succeed.