protected CassandraLeafCounter counter(final Counter.Key ckey,
final DynamicDelegatedSerializer<Object> serializer,
final ColumnSlice<String, Object> map,
final String marker) {
return new CassandraLeafCounter(ckey, this, marker)
.sync(new M2AwareStatisticalSummary(
getOrDefault( serializer, map.getColumnByName( "mean" ), DoubleSerializer.get() ).doubleValue(),
getOrDefault( serializer, map.getColumnByName( "variance" ), DoubleSerializer.get() ).doubleValue(),
getOrDefault( serializer, map.getColumnByName( "n" ), LongSerializer.get() ).longValue(),
getOrDefault( serializer, map.getColumnByName( "max" ), DoubleSerializer.get() ).doubleValue(),
getOrDefault( serializer, map.getColumnByName( "min" ), DoubleSerializer.get() ).doubleValue(),
getOrDefault( serializer, map.getColumnByName( "sum" ), DoubleSerializer.get() ).doubleValue(),
getOrDefault( serializer, map.getColumnByName( "m2" ), DoubleSerializer.get() ).doubleValue()),
getOrDefault( serializer, map.getColumnByName( "maxConcurrency" ),
IntegerSerializer.get() ).intValue());
}