# for the bug where the logging agent cannot start up if the file is
    # corrupted.
    Remove-Item `
      -Force `
      -ErrorAction Ignore `
      ("$STACKDRIVER_ROOT\LoggingAgent\Main\pos\winevtlog.pos\worker0\" +
       "storage.json")
    Log-Output ("Skip: Stackdriver logging agent is already installed")
    return
  }

  if (IsLoggingAgentInstalled) {

		wg.Add(1)
		go func() {
			defer wg.Done()
			<-hold
			err := RemoveAll(root)
			if err != nil {
				t.Errorf("unexpected error: %T, %q", err, err)
			}
		}()
	}
	close(hold) // let workers race to remove root
	wg.Wait()
}

// Test that reading from a pipe doesn't use up a thread.
func TestPipeThreads(t *testing.T) {
	switch runtime.GOOS {
	case "illumos", "solaris":

		// time so we can track it for the GC CPU limiter.
		//
		// Limiter event tracking might be disabled if we end up here
		// while on a mark worker.
		start := nanotime()
		track := pp.limiterEvent.start(limiterEventScavengeAssist, start)

		// Scavenge, but back out if the limiter turns on.
		released := h.pages.scavenge(bytesToScavenge, func() bool {