Contains a message about this GetMetricData operation, if the operation results in such a message.
An example of a message that
might be returned is Maximum number of allowed metrics exceeded. If there is a message, as much of the
operation as possible is still executed.
A message appears here only if it is related to the global GetMetricData operation. Any message
about a specific metric returned by the operation appears in the MetricDataResult object returned for that metric.
The metrics that are returned, including the metric name, namespace, and dimensions.
A token that marks the next batch of returned results.
Metadata pertaining to this request.