org.apache.flink.runtime.io.network.partition.hybrid

类 HsFileDataIndexCache

java.lang.Object

org.apache.flink.runtime.io.network.partition.hybrid.HsFileDataIndexCache

public class HsFileDataIndexCache
extends Object

A cache layer of hybrid data index. This class encapsulates the logic of the index's put and get, and automatically caches some indexes in memory. When there are too many cached indexes, it is this class's responsibility to decide and eliminate some indexes to disk.

字段概要

字段

限定符和类型	字段和说明
static Object	PLACEHOLDER Placeholder of cache entry's value.

构造器概要

构造器

构造器和说明
HsFileDataIndexCache(int numSubpartitions, Path indexFilePath, long numRetainedInMemoryRegionsMax, HsFileDataIndexSpilledRegionManager.Factory spilledRegionManagerFactory)

方法概要

限定符和类型	方法和说明
void	close() Close HsFileDataIndexCache, this will delete the index file.
Optional<org.apache.flink.runtime.io.network.partition.hybrid.HsFileDataIndexImpl.InternalRegion>	get(int subpartitionId, int bufferIndex) Get a region contains target bufferIndex and belong to target subpartition.
void	put(int subpartition, List<org.apache.flink.runtime.io.network.partition.hybrid.HsFileDataIndexImpl.InternalRegion> internalRegions) Put regions to cache.

从类继承的方法 java.lang.Object

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

字段详细资料

PLACEHOLDER

public static final Object PLACEHOLDER

Placeholder of cache entry's value. Because the cache is only used for managing region's elimination, does not need the real region as value.

构造器详细资料

HsFileDataIndexCache

public HsFileDataIndexCache(int numSubpartitions,
                            Path indexFilePath,
                            long numRetainedInMemoryRegionsMax,
                            HsFileDataIndexSpilledRegionManager.Factory spilledRegionManagerFactory)

方法详细资料

get

public Optional<org.apache.flink.runtime.io.network.partition.hybrid.HsFileDataIndexImpl.InternalRegion> get(int subpartitionId,
                                                                                                             int bufferIndex)

Get a region contains target bufferIndex and belong to target subpartition.

参数:

subpartitionId - the subpartition that target buffer belong to.

bufferIndex - the index of target buffer.

返回:

If target region can be founded from memory or disk, return optional contains target region. Otherwise, return Optional#empty();

put

public void put(int subpartition,
                List<org.apache.flink.runtime.io.network.partition.hybrid.HsFileDataIndexImpl.InternalRegion> internalRegions)

Put regions to cache.

参数:

subpartition - the subpartition's id of regions.

internalRegions - regions to be cached.

close

public void close()
           throws IOException

Close HsFileDataIndexCache, this will delete the index file. After that, the index can no longer be read or written.

抛出:

IOException