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

Class ChunkCache

java.lang.Object

org.apache.iotdb.db.engine.cache.ChunkCache

public class ChunkCache
extends java.lang.Object

This class is used to cache Chunk of ChunkMetaData in IoTDB. The caching strategy is LRU.

Method Summary

Modifier and Type	Method	Description
double	calculateChunkHitRatio()
void	clear()	clear LRUCache.
org.apache.iotdb.tsfile.read.common.Chunk	get(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData)
org.apache.iotdb.tsfile.read.common.Chunk	get(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData, boolean debug)
double	getAverageLoadPenalty()
long	getAverageSize()
long	getEvictionCount()
static ChunkCache	getInstance()
long	getMaxMemory()
boolean	isEmpty()
void	remove(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData)

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static ChunkCache getInstance()

get

public org.apache.iotdb.tsfile.read.common.Chunk get(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData)
                                              throws java.io.IOException

Throws:

java.io.IOException

get

public org.apache.iotdb.tsfile.read.common.Chunk get(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData,
                                                     boolean debug)
                                              throws java.io.IOException

Throws:

java.io.IOException

calculateChunkHitRatio

public double calculateChunkHitRatio()

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(org.apache.iotdb.tsfile.file.metadata.ChunkMetadata chunkMetaData)

isEmpty

public boolean isEmpty()