Page Life Expectancy (s) for DB Engine
Page Life Expectancy is number of seconds a page will stay in the buffer pool without references. High page life expectancy means that required data can be found in cache instead of going to hard drive.
Extremely low Page Life Expectancy values can be an indication of:
Too small memory on the system
Too small memory configured for SQL Server’s use
Poor index design
Check I/O system to verify how it handles the load, if values of Average Disk sec/Read and Average Disk sec/Write counters for object PhysicalDisk are high (usually higher than 10 msec.), it means your system may overloaded or opportunities exist for query and index improvement.
Buffer Pool can be overloaded because SQL Server works with high amount of tables simultaneously, or full scanning is used in place of search by criteria. Check SQL Server:Access Methods:Full Scans per Second counter to verify the problem.
You may use SQL Server Profiler and browse Showplan Statistics in the Performance category to find an application that cause full scanning.
Name | Description | Default Value |
Alert Priority | Defines Alert Priority. | Normal |
Alert Severity | Defines Alert Severity. | Error |
Enabled | Enables or disables the workflow. | Yes |
Generates Alerts | Defines whether the workflow generates an Alert. | Yes |
Interval (seconds) | The recurring interval of time in seconds in which to run the workflow. | 300 |
Number of samples | Indicates how many times a measured value should breach a threshold before the state is changed. | 6 |
Synchronization Time | The synchronization time specified by using a 24-hour format. May be omitted. |
|
Threshold | The collected value will be compared against this parameter. | 300 |
Timeout (seconds) | Specifies the time the workflow is allowed to run before being closed and marked as failed. | 200 |
Timeout for database connection (seconds) | The workflow will fail and register an event, if it cannot access the database during the specified period. | 15 |
Target | Microsoft.SQLServer.Windows.DBEngine | ||
Parent Monitor | System.Health.PerformanceState | ||
Category | PerformanceHealth | ||
Enabled | True | ||
Alert Generate | True | ||
Alert Severity | Error | ||
Alert Priority | Normal | ||
Alert Auto Resolve | True | ||
Monitor Type | Microsoft.SQLServer.Windows.MonitorType.DBEngine.PageLifeExpectancy | ||
Remotable | True | ||
Accessibility | Public | ||
Alert Message |
| ||
RunAs | Default |
<UnitMonitor ID="Microsoft.SQLServer.Windows.Monitor.DBEngine.PageLifeExpectancy" Accessibility="Public" Enabled="true" Target="SqlDiscW!Microsoft.SQLServer.Windows.DBEngine" ParentMonitorID="Health!System.Health.PerformanceState" Remotable="true" Priority="Normal" TypeID="Microsoft.SQLServer.Windows.MonitorType.DBEngine.PageLifeExpectancy" ConfirmDelivery="false">
<Category>PerformanceHealth</Category>
<AlertSettings AlertMessage="Microsoft.SQLServer.Windows.Monitor.DBEngine.PageLifeExpectancy.AlertMessage">
<AlertOnState>Error</AlertOnState>
<AutoResolve>true</AutoResolve>
<AlertPriority>Normal</AlertPriority>
<AlertSeverity>Error</AlertSeverity>
<AlertParameters>
<AlertParameter1>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/InstanceName$</AlertParameter1>
<AlertParameter2>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/MachineName$</AlertParameter2>
</AlertParameters>
</AlertSettings>
<OperationalStates>
<OperationalState ID="Normal" MonitorTypeStateID="Normal" HealthState="Success"/>
<OperationalState ID="Error" MonitorTypeStateID="Error" HealthState="Error"/>
</OperationalStates>
<Configuration>
<MachineName>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/MachineName$</MachineName>
<InstanceName>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/InstanceName$</InstanceName>
<ConnectionString>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/ConnectionString$</ConnectionString>
<MonitoringType>$Target/Property[Type="SqlDiscW!Microsoft.SQLServer.Windows.DBEngine"]/MonitoringType$</MonitoringType>
<IntervalSeconds>300</IntervalSeconds>
<SyncTime/>
<Threshold>300</Threshold>
<NumSamples>6</NumSamples>
<TimeoutSeconds>200</TimeoutSeconds>
<SqlTimeoutSeconds>15</SqlTimeoutSeconds>
<PerformanceCounterObject>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/PerformanceCounterObject$</PerformanceCounterObject>
</Configuration>
</UnitMonitor>