問題文
An engineer needs the samples of http_requests_total from the last five minutes as input to a function. Which expression produces a range vector, and what does the square bracket syntax mean?
選択肢
- http_requests_total @ 5m produces the range vector, because the at modifier pins the evaluation to a five-minute window.
- http_requests_total offset 5m selects the samples of the preceding five minutes, because the offset modifier widens the selection window to that duration.
- http_requests_total[5m] selects, for each matching series, the samples recorded within the preceding five minutes rather than a single value.
- sum_over_time(http_requests_total) produces the range vector, because the function name and its suffix declare the intent to look back over time.