private UsageRecord PingUpdate(uint key, UsageRecord oldValue)
{
var now = clock.GetMinutes();
// Saturating addition
var oldFrequency = oldValue.GetCurrentFrequency(now, halfLifeMinutes);
oldValue.frequency = Math.Max(oldFrequency + 1, oldFrequency);
oldValue.lastRead = now;
return(oldValue);
}
internal UsageRecord(IClock clock)
{
lastRead = clock.GetMinutes();
frequency = 1;
}