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TFS - XAML Build controller stops working–Part 2

Yesterday I blogged about a problem that I had with the XAML Build controllers. I reconfigured the /queue what seemed to solve the problem.

Unfortunately the problem reappeared after a few hours. Instead of getting a 404 error, this time the details exposed a 500 error code.

In the logs I noticed the following error message:

WebHost failed to process a request.

Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/17729775

Exception: System.ServiceModel.ServiceActivationException: The service '/queue/SampleCollection/Services/v4.0/MessageQueueService2.svc' cannot be activated due to an exception during compilation.  The exception message is: Memory gates checking failed because the free memory (419909632 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 (419909632 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: 2216

Whoops! It seems that our TFS server is desperate for some memory. And indeed, after adding some extra memory and a reboot it finally started to work.

Let’s move on to the next problem…

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