ReStream
Johann Schleier-Smith, Erik T. Krogen, Joseph M. Hellerstein · 2016
Real-time predictive applications can demand continuous and agile development, with new models constantly being trained, tested, and then deployed. Training and testing are done by replaying stored event logs, running new models in the context of historical data in a form of backtesting or "what if?" analysis. To replay weeks or months of logs while developers wait, we need systems that can stream event logs through prediction logic many times faster than the real-time rate. A challenge with high-speed replay is preserving sequential semantics while harnessing parallel processing power. The crux of the problem lies with causal dependencies inherent in the sequential semantics of log replay.