WebHost failed to process a request.
 Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/49648990
 Exception: System.ServiceModel.ServiceActivationException: The service '/WCF/SynCacheService.svc' cannot be activated due to an exception during compilation.  The exception message is: Memory gates checking failed because the free memory (140656640 bytes) is less than 5% of total memory.  As a result, the service will not be available for incoming requests.  To resolve this, either reduce the load on the machine or adjust the value of minFreeMemoryPercentageToActivateService on the serviceHostingEnvironment config element.. ---> System.InsufficientMemoryException: Memory gates checking failed because the free memory (140656640 bytes) is less than 5% of total memory.  As a result, the service will not be available for incoming requests.  To resolve this, either reduce the load on the machine or adjust the value of minFreeMemoryPercentageToActivateService on the serviceHostingEnvironment config element.
   at System.ServiceModel.Activation.ServiceMemoryGates.Check(Int32 minFreeMemoryPercentage, Boolean throwOnLowMemory, UInt64& availableMemoryBytes)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CheckMemoryCloseIdleServices(EventTraceActivity eventTraceActivity)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity)
   --- End of inner exception stack trace ---
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity)
   at System.ServiceModel.ServiceHostingEnvironment.EnsureServiceAvailableFast(String relativeVirtualPath, EventTraceActivity eventTraceActivity)
 Process Name: w3wp
 Process ID: 7636

Today, an error occurred in the project, and the above information is prompted. This is a mistake made when using WCF. If you have the same error, please check the sign and take your seat. Memory entry check failed because free memory is less than 5%.
To solve this problem, add a node on the corresponding Web.config of WCF. The node structure is as follows:

<configuration>  
  <system.serviceModel>
　　<serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" minFreeMemoryPercentageToActivateService="0"/>
    ......
  </system.serviceModel>
</configuration>

Under the system.Servicemodel node

<serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" minFreeMemoryPercentageToActivateService="0"/>

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