Caching & Performance Vocabulary
Performance optimization is a common topic. Know how to explain your approach clearly.
Caching Terms
| Term | Meaning |
|---|
| cache hit | Data found in cache — fast response |
| cache miss | Data not in cache — must fetch from DB |
| TTL (Time To Live) | How long cached data stays valid |
| cache invalidation | Removing stale data from cache |
| write-through | Write to cache and DB simultaneously |
| lazy loading | Load data into cache only when first requested |
Performance Vocabulary
- latency — time for a single request to complete
- throughput — number of requests handled per second
- bottleneck — the slowest part limiting overall performance
- profiling — measuring where time/resources are spent
Useful Phrases
- "I added a Redis cache with a 5-minute TTL to reduce database load."
- "The bottleneck was the N+1 query problem in the ORM."
- "After profiling, I found that 80% of latency came from a single slow query."