CompilerServerUnitTests.MultipleSimultaneousCompiles failed

[tmat]

http://dotnet-ci.cloudapp.net/job/roslyn_prtest_win_dbg_unit64/2290/console

  Microsoft.CodeAnalysis.CompilerServer.UnitTests.CompilerServerUnitTests.MultipleSimultaneousCompiles
      Assert.Equal() Failure
      Expected: 20
      Actual:   19
      Stack Trace:
        src\Compilers\Server\VBCSCompilerTests\CompilerServerTests.cs(259,0): at Microsoft.CodeAnalysis.CompilerServer.UnitTests.CompilerServerUnitTests.<Verify>d__35.MoveNext()
        --- End of stack trace from previous location where exception was thrown ---
           at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
           at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
           at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
        src\Compilers\Server\VBCSCompilerTests\CompilerServerTests.cs(1010,0): at Microsoft.CodeAnalysis.CompilerServer.UnitTests.CompilerServerUnitTests.<MultipleSimultaneousCompiles>d__63.MoveNext()
        --- End of stack trace from previous location where exception was thrown ---
           at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
           at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
        --- End of stack trace from previous location where exception was thrown ---
           at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
           at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
        --- End of stack trace from previous location where exception was thrown ---
           at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
           at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)

[tmat]

@dotnet/roslyn-compiler

[amcasey]

Failed again: Roslyn-Master-Signed-Release\20160106.1\xUnitResults

[jaredpar]

I believe the problem here is the Jenkins machine is under serious load. As a result the server simply can't keep up with the requests being sent and one of them falls back to a local compilation. That throws off the test which is expecting that all of them complete on the server.

Need to change the suite so that it accounts for this possibility.