Package org.apache.iotdb.db.engine.cache

Class TimeSeriesMetadataCache

java.lang.Object

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

public class TimeSeriesMetadataCache
extends java.lang.Object

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

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey

Method Summary

Modifier and Type	Method	Description
double	calculateTimeSeriesMetadataHitRatio()
void	clear()	clear LRUCache.
org.apache.iotdb.tsfile.file.metadata.TimeseriesMetadata	get(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key, java.util.Set<java.lang.String> allSensors, boolean ignoreNotExists, boolean debug)
double	getAverageLoadPenalty()
long	getAverageSize()
long	getEvictionCount()
static TimeSeriesMetadataCache	getInstance()
long	getMaxMemory()
boolean	isEmpty()
void	remove(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key)

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static TimeSeriesMetadataCache getInstance()

get

public org.apache.iotdb.tsfile.file.metadata.TimeseriesMetadata get(TimeSeriesMetadataCache.TimeSeriesMetadataCacheKey key,
                                                                    java.util.Set<java.lang.String> allSensors,
                                                                    boolean ignoreNotExists,
                                                                    boolean debug)
                                                             throws java.io.IOException

Throws:

java.io.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()