juniorCaching

What is Local Memory Caching?

Updated Apr 28, 2026

Short answer

Storing data in the RAM of the specific application instance where the code is running.

Deep explanation

Caching is essential for performance optimization. Storing data in the RAM of the specific application instance where the code is running. By reducing the need to access slower storage layers (like HDDs or remote databases), systems can achieve much lower latency.

Real-world example

Storing the results of a complex database query in Redis.

Common mistakes

  • Not setting a TTL, leading to the cache growing indefinitely or serving very old data.

Follow-up questions

  • Is cache persistent?

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