Using Logs to Increase Availability in Real-Time Main-Memory Database

Real-time main-memory databases are useful in real-time environments. They are often faster and provide more predictable execution of transactions than disk-based databases do. The most reprehensible feature is the volatility of the memory. In the RODAIN Database Architecture we solve this problem by maintaining a remote copy of the database in a stand-by node. We use logs to update the database copy on the hot stand-by. The log writing is often the most dominating factor in the transaction commit phase. With hot stand-by we can completely omit the disk update from the critical path of the transaction, thus providing more predictable commit phase execution, which is important when the transactions need to be finished within their deadlines.