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Cache stampede
See what happens to the database when many cache keys expire at the same moment — and how two small fixes stop it.
How it works
- 1When many keys are cached at the same time with the same expiry, they also expire together. Every request for them misses at once and hits the database.
- 2Jitter gives each key a slightly different expiry, so the misses spread out.
- 3Single-flight lets only one request refresh a key; the rest wait for that result instead of all querying the database.
Read the post: How to build an API for 100,000 requests a second
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