ServiceThrottlingBehavior.MaxConcurrentCalls Property
Gets or sets a value that specifies the maximum number of messages actively processing across a ServiceHost.
Namespace: System.ServiceModel.Description
Assembly: System.ServiceModel (in System.ServiceModel.dll)
Property Value
Type: System.Int32The upper limit of active messages in the service. The default is 16 times the processor count.
The MaxConcurrentCalls property specifies the maximum number of messages actively processing across a ServiceHost object. Each channel can have one pending message that does not count against the value of MaxConcurrentCalls until Windows Communication Foundation (WCF) begins to process it.
You can also set the values of this attribute by using the <serviceThrottling> element in an application configuration file.
 Caution |
|---|
MaxConcurrentCalls should be set to less than the SQL connection pool size in queued scenarios. |
The following code example shows the use of ServiceThrottlingBehavior from an application configuration file that sets the MaxConcurrentSessions, MaxConcurrentCalls, and MaxConcurrentInstances properties to 1 as an example. Real-world experience determines what the optimal settings are for any particular application.
<configuration>
<appSettings>
<!-- use appSetting to configure base address provided by host -->
<add key="baseAddress" value="http://localhost:8080/ServiceMetadata" />
</appSettings>
<system.serviceModel>
<services>
<service
name="Microsoft.WCF.Documentation.SampleService"
behaviorConfiguration="Throttled" >
<host>
<baseAddresses>
<add baseAddress="http://localhost:8080/SampleService"/>
</baseAddresses>
</host>
<endpoint
address=""
binding="wsHttpBinding"
contract="Microsoft.WCF.Documentation.ISampleService"
/>
<endpoint
address="mex"
binding="mexHttpBinding"
contract="IMetadataExchange"
/>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior name="Throttled">
<serviceThrottling
maxConcurrentCalls="1"
maxConcurrentSessions="1"
maxConcurrentInstances="1"
/>
<serviceMetadata
httpGetEnabled="true"
httpGetUrl=""
/>
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
</configuration>
<configuration>
<appSettings>
<!-- use appSetting to configure base address provided by host -->
<add key="baseAddress" value="http://localhost:8080/ServiceMetadata" />
</appSettings>
<system.serviceModel>
<services>
<service
name="Microsoft.WCF.Documentation.SampleService"
behaviorConfiguration="Throttled" >
<host>
<baseAddresses>
<add baseAddress="http://localhost:8080/SampleService"/>
</baseAddresses>
</host>
<endpoint
address=""
binding="wsHttpBinding"
contract="Microsoft.WCF.Documentation.ISampleService"
/>
<endpoint
address="mex"
binding="mexHttpBinding"
contract="IMetadataExchange"
/>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior name="Throttled">
<serviceThrottling
maxConcurrentCalls="1"
maxConcurrentSessions="1"
maxConcurrentInstances="1"
/>
<serviceMetadata
httpGetEnabled="true"
httpGetUrl=""
/>
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
</configuration>
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
