title: TeamCity NUnit build step ends with long delay?
body: <p>I'm running a TeamCity 8.1.2 build server with 3 agents on AWS cloud.</p>
  
  <p>I'm experiencing unusually long delays following completion of an NUnit build step.  I have just over 30,000 unit tests running, which take around 3 mins to complete.  However the build log shows the step takes 11 mins to complete (at least, sometimes 15 mins), most of which seems to be due to a delay at the end of the step, internal to TeamCity.</p>
  
  <p><em>EDIT</em> This delay has increased over time, the build used to complete within 5-6 mins.</p>
  
  <p>Here's an excerpt from the build log of a fairly quick run.  Note the 7 min delay between 'Process exited' and '##teamcity':</p>
  
  <pre><code>[22:39:17]Step 6/7: Run Unit Tests (NUnit) (11m:26s)
  [22:39:17][Step 6/7] ##teamcity[buildStatisticValue key='buildStageDuration:buildStepRUNNER_20' value='0.0']
  [22:39:17][Step 6/7] Starting: D:\BuildAgent\plugins\dotnetPlugin\bin\JetBrains.BuildServer.NUnitLauncher.exe #TeamCityImplicit
  [22:39:17][Step 6/7] in directory: D:\builds\X.Web\Build
  [22:39:30][Step 6/7] Start TeamCity NUnit Test Runner
  [22:39:30][Step 6/7] Running NUnit-2.6.3 tests under .NET Framework v4.0 x64
  [22:39:39][Step 6/7] X.Tests.dll (2m:39s)
  [22:42:59][Step 6/7] X.ServiceInterface.Tests.dll (1s)
  [22:43:04][Step 6/7] X.Data.Tests.dll (24s)
  [22:43:30][Step 6/7] Process exited with code 0
  [22:50:44][Step 6/7] ##teamcity[buildStatisticValue key='buildStageDuration:buildStepRUNNER_20' value='686467.0']
  [22:50:44]Step 7/7: Pack Feed NuGet Packages (NuGet Pack) (6s)
  </code></pre>
  
  <p>Any ideas?  I'll drop a support ticket to jetbrains, but I thought I'd throw this out to the community in case someone's seen it before.  Thanks in advance for any help.</p>