Count-Min Sketch: The Art and Science of Estimating Stuff

This post delves into the exciting world of probabilistic data structures and Redis modules. It highlights that large-scale low-latency data processing is challenging, but Redis' high performance and versatility make it ideal for solving such challenges. The Count-Min Sketch (CMS) is a probabilistic data structure that sacrifices some accuracy to gain space, making it useful in scenarios where reduced accuracy is acceptable. CMS works by aggregating the count of all items in your dataset into several counter arrays and returning the item's minimum count upon query. It has been a Redis module for several years and was recently rewritten as part of the RedisBloom module v2.0. The post also discusses other probabilistic data structures, such as HyperLogLog, and their applications in high-scale low-latency data processing.