Caching easy
What is the primary architectural goal of introducing a cache into a system?
- A To serve as the primary persistent source of truth for all application state and data.
- B To increase the system's total storage capacity by utilizing high-density disk arrays.
- C To reduce read latency and decrease the overall load on the underlying data store.
- D To provide a secure, encrypted storage layer for sensitive user credentials at rest.
Answer: C. To reduce read latency and decrease the overall load on the underlying data store.
The primary goal of a cache is detailed in the **read-heavy** workload optimization: it stores copies of frequently accessed data in fast storage (like RAM) to reduce the time it takes to retrieve that data (latency) and to reduce the workload (read throughput) on the slower, persistent database layer.
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- Your cache uses an LRU (Least Recently Used) eviction policy. When the cache is full, which item is removed?
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