DevOps Interview DropAdvanced TierScenario+50 XP on read
When would you scale vertically instead of horizontally?
Core Summary
Go vertical when the bottleneck doesn't split: database buffer cache, cache memory, network bandwidth on one node, a single-threaded lock. Go horizontal when the work partitions cleanly. The real question isn't which is better, it's whether the thing that's saturated can be divided across machines at all.
Hints
Hint 1: Vertical when the bottleneck is not parallelizable
Hint 2: Horizontal when you can shard the data or split the traffic
Hint 3: Some systems force a choice: databases are harder to scale horizontally than stateless services
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