Does Rio provide reliability or availability?
Rio’s focus is reliability (not losing data). In general, availability (being able to access data continuously) requires hardware replication. Rio can provide availability in much the same way that disks can. For example, a cheap serial line from the memory card to another computer would provide availability while rebooting or during hardware failure. With safe sync, Rio can provide availability with dual-ported disks (as with any disk-based system). We are exploring using DEC’s Memory Channel to provide high availability and reliability in the face of hardware failures. • Does Rio survive hardware failure? Rio’s focus is on surviving software crashes, because prior studies indicate that software failures outnumber hardware failures 10-to-1. Rio can be extended to survive hardware failures. A cheap serial line from the memory card to another computer allows data to be transferred to another machine in case of hardware failure. Safe sync with dual-ported disks allows Rio to survive hard
