On Tue 23-04-19 16:38:43, Pavel Tatashin wrote: > sparsemem section size determines the maximum size and alignment that > is allowed to offline/online memory block. The bigger the size the less > the clutter in /sys/devices/system/memory/*. On the other hand, however, > there is less flexability in what granules of memory can be added and > removed. > > Recently, it was enabled in Linux to hotadd persistent memory that > can be either real NV device, or reserved from regular System RAM > and has identity of devdax. > > The problem is that because ARM64's section size is 1G, and devdax must > have 2M label section, the first 1G is always missed when device is > attached, because it is not 1G aligned. > > Allow, better flexibility by making section size configurable. Is there any inherent reason (64k page size?) that enforces such a large memsection? -- Michal Hocko SUSE Labs
