Web Infrastructure: Requests rejected due to application level throttle

Microsoft.LS.2013.Monitoring.UnitMonitor.ThresholdPC.WebInfra.PERF_WEBAUTH_REQUESTS_FAILED_APP_THROTTLE (UnitMonitor)

Knowledge Base article:

Summary

The number of requests that were rejected because per-application queue limit was exceeded

Causes

This value may grow if an application is overloaded because of a large number of requests. It may also represent requests that are waiting on other services to respond or software errors resulting in no response being returned.

Resolutions

If the traffic volume is overloading the server, reduce traffic by adding additional servers to the pool. If the issue is caused by another system or a software error, restart the website and report the problem to Microsoft.

Element properties:

TargetMicrosoft.LS.2013.Dependency.WebInfra.ApplicationPool
Parent MonitorSystem.Health.PerformanceState
CategoryPerformanceHealth
EnabledTrue
Alert GenerateTrue
Alert SeverityError
Alert PriorityNormal
Alert Auto ResolveTrue
Monitor TypeMicrosoft.LS.2013.Performance.Double.DeltaThresholdMonitor
RemotableTrue
AccessibilityPublic
Alert Message
[LYNC] The number of requests that were rejected because per-application queue limit was exceeded
Perf Object Name:
Perf Counter Name: WEB - Requests Exceeded Per-App Limit
Perf Counter Value: {0}
Error Threshold: 3
Warning Threshold: 1
Delta Window Size: 3
Dynamic Instance. Name: Application Pool DependencyId: ApplicationPool Symbol Prefix: WEBAUTH Category: LS:WEB - Throttling and Authentication Discover Interval: 14400 Excluded Instances:
Please see the 'Product Knowledge' and the 'Alert Context' tab on Alert Properties view for more information.
RunAsDefault

Source Code:

<UnitMonitor ID="Microsoft.LS.2013.Monitoring.UnitMonitor.ThresholdPC.WebInfra.PERF_WEBAUTH_REQUESTS_FAILED_APP_THROTTLE" Accessibility="Public" Enabled="true" Target="Microsoft.LS.2013.Dependency.WebInfra.ApplicationPool" ParentMonitorID="Health!System.Health.PerformanceState" Remotable="true" Priority="Normal" TypeID="Microsoft.LS.2013.Performance.Double.DeltaThresholdMonitor" ConfirmDelivery="false">
<Category>PerformanceHealth</Category>
<AlertSettings AlertMessage="Alert_The_number_of_requests_that_were_rejected_because_per_application_queue_limit_was_exceeded">
<AlertOnState>Error</AlertOnState>
<AutoResolve>true</AutoResolve>
<AlertPriority>Normal</AlertPriority>
<AlertSeverity>Error</AlertSeverity>
<AlertParameters>
<AlertParameter1>$Data/Context/Value$</AlertParameter1>
</AlertParameters>
</AlertSettings>
<OperationalStates>
<OperationalState ID="Microsoft.LS.2013.Monitoring.UnitMonitor.ThresholdPC.WebInfra.PERF_WEBAUTH_REQUESTS_FAILED_APP_THROTTLE_OverThreshold" MonitorTypeStateID="OverThreshold" HealthState="Error"/>
<OperationalState ID="Microsoft.LS.2013.Monitoring.UnitMonitor.ThresholdPC.WebInfra.PERF_WEBAUTH_REQUESTS_FAILED_APP_THROTTLE_UnderThreshold" MonitorTypeStateID="UnderThreshold" HealthState="Success"/>
<OperationalState ID="Microsoft.LS.2013.Monitoring.UnitMonitor.ThresholdPC.WebInfra.PERF_WEBAUTH_REQUESTS_FAILED_APP_THROTTLE_UnderThresholdOverThreshold" MonitorTypeStateID="UnderThresholdOverThreshold" HealthState="Warning"/>
</OperationalStates>
<Configuration>
<ComputerName>$Target/Host/Host/Host/Host/Property[Type="Windows!Microsoft.Windows.Computer"]/NetworkName$</ComputerName>
<CounterName>WEB - Requests Exceeded Per-App Limit</CounterName>
<ObjectName>LS:WEB - Throttling and Authentication</ObjectName>
<InstanceName>$Target/Property[Type="Microsoft.LS.2013.Dependency"]/Id$</InstanceName>
<AllInstances>false</AllInstances>
<Frequency>900</Frequency>
<WarningThreshold>1</WarningThreshold>
<ErrorThreshold>3</ErrorThreshold>
<NumSamples>3</NumSamples>
</Configuration>
</UnitMonitor>