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FFWD: Latency-Aware Event Stream Processing via Domain-Specific Load-Shedding Policies

Tools and applications for event stream processing and real-time analytics are getting a huge hype these days on a wide range of application scenarios, from the smallest Internet of Things (IoT) embedded sensor to the most popular Social Network feed. Unfortunately, dealing with this kind of input rises some issues that can easily mine the real-time analysis requirement due to an unexpected overload of the system, this happens as the processing time may strongly depend on the single event content, while the event arrival rate may vary unpredictably over time. In this work, we propose Fast Forward With Degradation (FFWD), a latency-aware load shedding framework that exploits performance degradation techniques to adapt the throughput of the application to the size of the input, allowing the system to have a fast and reliable response time in case of overloading. Moreover, we show how different domain-specific policies can guarantee a reasonable accuracy of the aggregated output metrics.