Merge pull request #104195 from mamccrea/event-rate

Stream Analytics: add metrics for su increase

Author: PRMerger13

articles/stream-analytics/stream-analytics-streaming-unit-consumption.md

@@ -55,6 +55,8 @@ Note that a job with complex query logic could have high SU% utilization even wh
 
 SU% utilization may suddenly drop to 0 for a short period before coming back to expected levels. This happens due to transient errors or system initiated upgrades. Increasing number of streaming units for a job might not reduce SU% Utilization if your query is not [fully parallel](https://docs.microsoft.com/azure/stream-analytics/stream-analytics-parallelization).
 
+While comparing utilization over a period of time, use [event rate metrics](stream-analytics-monitoring.md). InputEvents and OutputEvents metrics show how many events were read and processed. There are metrics that indicate number of error events as well, such as deserialization errors. When the number of events per time unit increases, SU% increases in most cases.
+
 ## Stateful query logic in temporal elements
 One of the unique capability of Azure Stream Analytics job is to perform stateful processing, such as windowed aggregates, temporal joins, and temporal analytic functions. Each of these operators keeps state information. The maximum window size for these query elements is seven days.