Query Details
let latencyCachedData = materialize(SigninLogs | where TimeGenerated > ago(24h) | project TimeGenerated, IngestionLatency = (_TimeReceived - TimeGenerated) | extend IngestionLatencyInMinutes = (IngestionLatency / 1m)); union (latencyCachedData | evaluate rolling_percentile(IngestionLatencyInMinutes, 95, TimeGenerated, 15m, 5) | extend pcnt=95), (latencyCachedData | evaluate rolling_percentile(IngestionLatencyInMinutes, 99, TimeGenerated, 15m, 5) | extend pcnt=99)
The query calculates the ingestion latency for sign-in logs in the past 24 hours. It then calculates the 95th and 99th percentile of the ingestion latency over a rolling 15-minute window with a 5-minute interval.

Rod Trent
Released: March 26, 2020
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