Data streams abound in the world of Big Data: Twitter, search queries, stock quotes, website analytics, sensor data to name a few. Yet, popular approaches for data processing at this scale are based on MapReduce: a batch-oriented framework; in other cases, there are proprietary stream processing systems, or ad-hoc solutions for particular problems.
We understand that the greatest value from data is sometimes derived by processing it as soon as we get it. S4 is a general-purpose open platform built from the ground up to process data streams — we mean process data as it arrives, one event at a time; not buffered in arbitrary batches.
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