In order to be able to get a sense for the absolute maximum number of donations our system can handle before messages start backing up in the queue, I would like to start tracking how quickly the donations queue consumer is adding new donations to civicrm.
Note: This is not total number of messages consumed in one run. We'd need a new counter for new donations added.
It would be especially useful, if this was done in such a way that an accurate rate of consumption could be captured regardless of the load volume during any particular run (assuming that there is at least one valid donation to work with). That way, we could detect performance hits in the off-season.