Backend · Mid-level · Theory

You have a popular key in Redis with a TTL, and every time it expires, the database gets a load spike and starts to slow down. What's going on, and how do you fix it?

~4 min by voice

How to approach it

The interviewer wants to see whether you recognize a cache stampede (dogpile, thundering herd) and understand its mechanism. The second thing that matters: whether you can propose several layers of protection rather than just "increase the TTL" or "give the database more resources".

Have you seen this question in a real interview?

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Topics

caching cache stampede

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min