Right, there are physical limitations to how physical states can be altered (density, speed, energy) with enough persistence against entropic decay. Persistence is an abstraction to push the renewal burden onto backup maintainers. I'd much rather see work directed towards a self-repairing style of persistence.

According to the conclusion in the white paper, they tested for endurance only to 10^7 with no degradation. Obviously that is not enough for a real system.

Without constantly loading cached data into dram the number of writes to it would be significantly lower.

Do you know good sources on that? Thanks.