code: func (c *CCache) DelMetric(rawMetric schema.MKey) (int, int) {
  	if c == nil {
  		return 0, 0
  	}
  	archives, series := 0, 0
  
  	c.Lock()
  	defer c.Unlock()
  
  	archs, ok := c.metricRawKeys[rawMetric]
  	if !ok {
  		return archives, series
  	}
  
  	metric := schema.AMKey{MKey: rawMetric}
  	for arch := range archs {
  		metric.Archive = arch
  		delete(c.metricCache, metric)
  		c.accnt.DelMetric(metric)
  		archives++
  	}
  
  	delete(c.metricRawKeys, rawMetric)
  	series++
  
  	return series, archives
  }
docs: // takes a raw key and deletes all archives associated with it from cache