org.apache.iotdb.db.engine.cache

类 TimeSeriesMetadataCache

java.lang.Object

org.apache.iotdb.db.engine.cache.TimeSeriesMetadataCache

public class TimeSeriesMetadataCache
extends Object

This class is used to cache TimeSeriesMetadata in IoTDB. The caching strategy is LRU.

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey

方法概要

限定符和类型	方法和说明
double	calculateTimeSeriesMetadataHitRatio()
void	clear() clear LRUCache.
TimeseriesMetadata	get(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key, Set<String> allSensors, boolean ignoreNotExists, boolean debug)
double	getAverageLoadPenalty()
long	getAverageSize()
long	getEvictionCount()
static TimeSeriesMetadataCache	getInstance()
long	getMaxMemory()
boolean	isEmpty()
void	remove(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key)

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

方法详细资料

getInstance

public static TimeSeriesMetadataCache getInstance()

get

public TimeseriesMetadata get(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key,
                              Set<String> allSensors,
                              boolean ignoreNotExists,
                              boolean debug)
                       throws IOException

抛出:

IOException

calculateTimeSeriesMetadataHitRatio

public double calculateTimeSeriesMetadataHitRatio()

getEvictionCount

public long getEvictionCount()

getMaxMemory

public long getMaxMemory()

getAverageLoadPenalty

public double getAverageLoadPenalty()

getAverageSize

public long getAverageSize()

clear

public void clear()

clear LRUCache.

remove

public void remove(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key)

isEmpty

public boolean isEmpty()