diff --git a/input/carbon/carbon_test.go b/input/carbon/carbon_test.go
index 41522d384c..2bfd29034d 100644
--- a/input/carbon/carbon_test.go
+++ b/input/carbon/carbon_test.go
@@ -105,6 +105,8 @@ func test_handleMessage(worker int, t *testing.T) map[string]int {
 			t.Fatal(err)
 		}
 	}
+	// as soon as this function ends, the server will close the socket.  We need to sleep here
+	// to ensure that the packets have time to be procesed by the kernel and passed to the server.
 	time.Sleep(time.Millisecond * 100)
 	return metrics
 }