"If you're looking at performance and you want to get some quick wins, the obvious place to start is caching. Caching as a concept is focused exclusively around improving performance. It's been used in disk controllers, processors, and other hardware devices since nearly the beginning of computing. Various software methods have been devised to do caching as well. Fundamentally caching has one limitation — managing updates — and several decisions. In this article, we'll explore the basic options for caching and their impact on performance."

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