Question 490
An ALB-backed web tier sees variable traffic while CPU remains low because most work waits on downstream I/O. Which autoscaling metric can directly reflect request load per healthy target?
Explanation
Correct Answer
Per-target request demand responds to changes in fleet size and can track I/O-bound web traffic better than CPU.
Incorrect Answers
Total requests do not decrease per target when capacity doubles.
Available root filesystem GiB does not directly measure incoming ALB requests per serving target. Choose a scaling signal that correlates with actual work, such as ALB request count per target.
DNS resolvers cache lookups and may reuse an answer for many HTTP requests; DNS question counts do not directly represent load per ALB target.






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