"However, I wonder how the modern UNIX OS will work with a system like this without block devices at all." I don't think that's how it works - I think you get

"However, I wonder how the modern UNIX OS will work with a system like this without block devices at all." I don't think that's how it works - I think you get a special driver that presents the fast-storage-in-dimm-slot as a block device. So you still have a block device, it's just faster. Right ?