Why use add instead of set when warming a cache?
An add only writes if the key is absent. A warming process copying a snapshot could otherwise overwrite a newer value that live traffic wrote moments earlier. Add-only inserts let live writes win, so warming can never make the cache staler.
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Caches That Survive Change: Warming, CDC Invalidation and Partitioning Apart From the DatabaseResizing a cache, replacing a node or failing over a region causes cold starts. How warming, log-driven invalidation and separate partitioning prevent them.
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