Scaling Reads easy
In a caching system, what is a 'Cache Miss'?
- A When the cache server crashes.
- B When the requested data is not found in the cache, forcing the application to fetch it from the database.
- C When the data in the cache is corrupt.
- D When the cache is full.
Answer: B. When the requested data is not found in the cache, forcing the application to fetch it from the database.
A Miss is normal. It simply means the faster storage (RAM) didn't have the item, so the system must fallback to the slower storage (Disk/DB) to retrieve it.
One system design question a day, with spaced repetition so the ones you miss come back.
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