in mutornadomon/monitor.py [0:0]
def _reset_ephemeral(self):
"""Reset ephemeral statistics.
For some things, rather than recording all values or just the latest
value, we want to record the highest or lowest value since the last
time stats were sampled. This function resets those gauges.
"""
self._MIN_GAUGES = {}
self._MAX_GAUGES = {}