* true iff the "request" dimension is to be included;
*/
protected List<MetricDatum> latencyMetricOf(MetricType metricType,
Request<?> req, Object response, boolean includesRequestType) {
AWSRequestMetrics m = req.getAWSRequestMetrics();
TimingInfo root = m.getTimingInfo();
final String metricName = metricType.name();
List<TimingInfo> subMeasures =
root.getAllSubMeasurements(metricName);
if (subMeasures != null) {
List<MetricDatum> result =
new ArrayList<MetricDatum>(subMeasures.size());
for (TimingInfo sub : subMeasures) {
if (sub.isEndTimeKnown()) { // being defensive