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• There are > 0 commits in the engine's commit pipeline
• The number of completed commits in the pipeline has not changed for a configurable period of time
• Stuck alert events are now only emitted if the stuck condition has persisted through two stuck alert threshold checks. This prevents a 'false positve' alert from occurring in the case where an engine has been idle for more than the stuck alert threshold and a new transaction is started just before a stuck engine check is made.
• A message or event handler is hung and preventing the engine's multiplexer thread from processing further events
• The stuck condition above remains present for 2 consecutive stuck engine checks. An alert will only be raised on the second stuck engine check which confirms that the condition is persistent. 
• Per stuck engine check either a HungTransactionPipeline or HungEventHandler will be reported, not both, and HungTransactionPipeline takes precedence. Stuck alerts are meant to raise a warning that an administrator should investigate engine health, and make a deeper determination of possible root causes. Upon seeing that StuckAlertEvent has been raised, thread dumps should be taken, and stats and trace logs should be examined to determine if there is a serious issue. 

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