Pronto: High availability for standard off-the-shelf databases

Enterprise applications typically store their state in databases. If a database fails, the application is unavailable while the database recovers. Database recovery is time consuming because it involves replaying the persistent transaction log. To isolate end users from database failures we introduce Pronto, a protocol to orchestrate the transaction processing by multiple, standard databases so that they collectively implement the illusion of a single, highly available database. Pronto is a novel replication protocol that handles non-determinism without relying on perfect failure detection, does not require any modifications in existing applications and databases, and allows databases from different providers to be part of the replicated compound.