問題文
A detector is configured to fire when a metric stays above fifty for five minutes. The team receives an alert, but when they open the detector later the chart shows values below fifty for that whole period. What explains this?
選択肢
- Some data points arrived several minutes late, so at evaluation time the engine saw only the high values that had arrived and fired; the late points are later stored with their correct timestamps, which makes the chart look as if the condition was never met.
- The alert was sent by a different rule of the same detector, one whose condition uses a lower threshold; the chart the team opened later belongs to a rule that stayed quiet.
- The detector evaluated a different signal than the chart shows, because a detector created from a chart keeps its own copy of the signal and the two drift apart whenever the chart is edited afterwards by anyone.
- The chart is applying a rollup that averages away the peak, so the values were above fifty at native resolution but the chart is showing a coarser resolution; changing the chart's time range to a shorter window will reveal the peak that caused the alert to be sent.