Ricerc@Sapienza

Distributed stream processing systems are today gaining momentum as a tool to perform analytics on continuous data streams. Load shedding is a technique used to handle unpredictable spikes in the input load whenever available computing resources are not adequately provisioned. In this paper, we propose Load-Aware Shedding (LAS), a novel load shedding solution that, unlike previous works, does not rely neither on a pre-defined cost model nor on any assumption on the tuple execution duration.

We revisit Byzantine-tolerant reliable broadcast algorithms in multi-hop networks. To tolerate up to f Byzantine nodes, previous solutions require an exponential number of messages to be sent over the network. We propose optimizations that preserve the safety and liveness properties of the original algorithms, while highly decreasing their observed message complexity when simulated on two families of random graphs.