On Mon, Mar 12, 2018 at 03:32:12PM +0100, Ingo Molnar wrote: > > * Kirill A. Shutemov <kir...@shutemov.name> wrote: > > > > We can of course bike shed / benchmark this once my desktop refresh > > > sports this feature, but ISTR this being one of the very first things > > > Ingo mentioned when we started this whole 5L thing. > > > > I would rather not fix the problem that may not actually exist. :) > > That 5 level pagetables involve more overhead is a realy problem. > > By default we should only enable 5-level paging if memory mappings exist in > the memory map that require the extended physical memory space.
Does it mean that if a machine supports 5lvl but has phisycal memory installed fitting the 4lvl space, and has memory hotplug supported, adding more memory won't have effect until next reboot?
