How does the Machine recover from software errors? If it has only persistent RAM, then when some important program goes bonkers (it always goes), there is no luxury of pressing the reset button to get back to a pristine state.
Taking into account the possibility of memory corruption, I think ultimately they won't get away without some sort of checkpointing to external storage.
To actually take advantage of persistent RAM and have fast restarts with no rollback, I bet early solutions will just partition the RAM into "bonkers-prone software" and "data" parts, with reboots involving a complete wipe of the former. Then somebody will submit Linux patches to keep some application or kernel data in the data part and hell knows where it goes from there.
And BTW, the announcement doesn't say they already have persistent RAM.
My guess is that there would be a microkernel service that is the core OS, like the BIOS, and it could be instructed to actively wipe the memory and reload the boot files when the machine freezes
To actually take advantage of persistent RAM and have fast restarts with no rollback, I bet early solutions will just partition the RAM into "bonkers-prone software" and "data" parts, with reboots involving a complete wipe of the former. Then somebody will submit Linux patches to keep some application or kernel data in the data part and hell knows where it goes from there.
And BTW, the announcement doesn't say they already have persistent RAM.