I have a logging level I call "log lots" where it will log the first time with probability 1, but as it hits more often the same line, it will log with lower and lower probability bottoming out around 1/20000 times. Sort of a "log with probability proportional to the unlikiness of the event". So if I get e.g. sporadic failures to some back end, I will see them all, but if it goes down hard I will see it is still down but also be able to read other log msgs.