+#XXX the test is relying on one-second accuracy, which is too tight.
+# The measured time is only one-second precision, so certain to sometime
+# straddle a boundary, even ignoring scheduling and I/O-wait issues.
+# Consider a factor of (?) two, in the retry section of the conf/ file
+# and +1 /2 after the diff operation (runtest:463).
+#