Package org.apache.hadoop.hdfs.server.blockmanagement

Class BlockInfoStriped

java.lang.Object

org.apache.hadoop.hdfs.protocol.Block

org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo

org.apache.hadoop.hdfs.server.blockmanagement.BlockInfoStriped

All Implemented Interfaces:

Comparable<org.apache.hadoop.hdfs.protocol.Block>, org.apache.hadoop.io.Writable, org.apache.hadoop.util.LightWeightGSet.LinkedElement

@Private
public class BlockInfoStriped
extends BlockInfo

Subclass of BlockInfo, presenting a block group in erasure coding. We still use triplets to store DatanodeStorageInfo for each block in the block group, as well as the previous/next block in the corresponding DatanodeStorageInfo. For a (m+k) block group, the first (m+k) triplet units are sorted and strictly mapped to the corresponding block. Normally each block belonging to group is stored in only one DataNode. However, it is possible that some block is over-replicated. Thus the triplet array's size can be larger than (m+k). Thus currently we use an extra byte array to record the block index for each triplet.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BlockInfoStriped.StorageAndBlockIndex	This class contains datanode storage information and block index in the block group.

Field Summary

Fields inherited from class org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo

EMPTY_ARRAY, triplets

Fields inherited from class org.apache.hadoop.hdfs.protocol.Block

BLOCK_FILE_PREFIX, blockFilePattern, METADATA_EXTENSION, metaFilePattern, metaOrBlockFilePattern

Constructor Summary

Constructors

Constructor	Description
BlockInfoStriped(org.apache.hadoop.hdfs.protocol.Block blk, org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy ecPolicy)

Method Summary

Modifier and Type	Method	Description
org.apache.hadoop.hdfs.protocol.BlockType	getBlockType()
int	getCellSize()
short	getDataBlockNum()
org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy	getErasureCodingPolicy()
short	getParityBlockNum()
short	getRealDataBlockNum()	If the block is committed/completed and its length is less than a full stripe, it returns the the number of actual data blocks.
short	getRealTotalBlockNum()
Iterable<BlockInfoStriped.StorageAndBlockIndex>	getStorageAndIndexInfos()
byte	getStorageBlockIndex(DatanodeStorageInfo storage)
short	getTotalBlockNum()
final boolean	isStriped()
int	numNodes()	Count the number of data-nodes the block currently belongs to (i.e., NN has received block reports from the DN).
long	spaceConsumed()

Methods inherited from class org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo

convertToBlockUnderConstruction, delete, equals, getBlockCollectionId, getBlockUCState, getCapacity, getDatanode, getNext, getReplication, getStorageInfos, getUnderConstructionFeature, hashCode, isComplete, isCompleteOrCommitted, isDeleted, isUnderRecovery, moveBlockToHead, setBlockCollectionId, setGenerationStampAndVerifyReplicas, setNext, setReplication

Methods inherited from class org.apache.hadoop.hdfs.protocol.Block

appendStringTo, compareTo, filename2id, getBlockId, getBlockId, getBlockName, getGenerationStamp, getGenerationStamp, getNumBytes, isBlockFilename, isMetaFilename, matchingIdAndGenStamp, metaToBlockFile, readFields, readId, set, setBlockId, setGenerationStamp, setNumBytes, toString, toString, write, writeId

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

BlockInfoStriped

public BlockInfoStriped(org.apache.hadoop.hdfs.protocol.Block blk,
 org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy ecPolicy)

Method Details

getTotalBlockNum

public short getTotalBlockNum()

getDataBlockNum

public short getDataBlockNum()

getParityBlockNum

public short getParityBlockNum()

getCellSize

public int getCellSize()

getRealDataBlockNum

public short getRealDataBlockNum()

If the block is committed/completed and its length is less than a full stripe, it returns the the number of actual data blocks. Otherwise it returns the number of data units specified by erasure coding policy.

getRealTotalBlockNum

public short getRealTotalBlockNum()

getErasureCodingPolicy

public org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy getErasureCodingPolicy()

getStorageBlockIndex

@VisibleForTesting
public byte getStorageBlockIndex(DatanodeStorageInfo storage)

spaceConsumed

public long spaceConsumed()

isStriped

public final boolean isStriped()

Specified by:

isStriped in class BlockInfo

getBlockType

public org.apache.hadoop.hdfs.protocol.BlockType getBlockType()

Specified by:

getBlockType in class BlockInfo

numNodes

public int numNodes()

Description copied from class: BlockInfo

Count the number of data-nodes the block currently belongs to (i.e., NN has received block reports from the DN).

Specified by:

numNodes in class BlockInfo

getStorageAndIndexInfos

public Iterable<BlockInfoStriped.StorageAndBlockIndex> getStorageAndIndexInfos()