CPU Percentage Interrupt Time (Windows Server 2008 R2)

Microsoft.Windows.Server.2008.R2.Processor.PercentInterruptTime (UnitMonitor)

Monitors the CPU Percentage Interrupt Time in Windows Server 2008 R2 Operating System.

Knowledge Base article:


The % Interrupt Time (Processor Information\% Interrupt Time) for the processor has exceeded the threshold. Overall system performance may significantly diminish which will result in poor operating system and application performance.

% Interrupt Time is the time the processor spends receiving and servicing hardware interrupts during sample intervals. This value is an indirect indicator of the activity of devices that generate interrupts, such as the system clock, the mouse, disk drivers, data communication lines, network interface cards and other peripheral devices. These devices normally interrupt the processor when they have completed a task or require attention.

This monitor is only valid for Windows Server 2008 R2 Operating System.


A high % Interrupt Time most often indicates that there is a problem with a hardware device.


To view recent Processor\% Interrupt Time history you can use the following view:

Start Processor Performance View

The % Interrupt Time counter will not specifically identify the device that is causing a high % Interrupt Time. To identify the device use Kernrate Viewer (KrView.exe) or Process Trace Information events to determine which ISRs are being dispatched most frequently.

Once the device has been identified the vendor should be contacted to determine a final resolution.


For more information about the Kernrate Viewer, see the Microsoft Download Center Web site at http://go.microsoft.com/fwlink/?LinkId=27748.

For more information about the processor object, see the Microsoft Corporation Web site at http://go.microsoft.com/fwlink/?LinkId=27758.

For more information about analyzing processor activity, see the Microsoft® Windows 2000 Resource Kits Web site at http://go.microsoft.com/fwlink/?LinkId=27678.

Element properties:

Parent MonitorSystem.Health.PerformanceState
Instance NameProcessor Information
Counter Name\% Interrupt Time
Alert GenerateFalse
Alert Auto ResolveTrue
Monitor TypeSystem.Performance.ConsecutiveSamplesThreshold

Source Code:

<UnitMonitor ID="Microsoft.Windows.Server.2008.R2.Processor.PercentInterruptTime" Accessibility="Public" Enabled="false" Target="Server2008!Microsoft.Windows.Server.2008.Processor" ParentMonitorID="SystemHealth!System.Health.PerformanceState" Remotable="true" Priority="Normal" TypeID="SystemPerf!System.Performance.ConsecutiveSamplesThreshold" ConfirmDelivery="false">
<OperationalState ID="OverThreshold" MonitorTypeStateID="ConditionTrue" HealthState="Error"/>
<OperationalState ID="UnderThreshold" MonitorTypeStateID="ConditionFalse" HealthState="Success"/>
<CounterName>% Interrupt Time</CounterName>
<ObjectName>Processor Information</ObjectName>