org.apache.hadoop.hbase

Class HDFSBlocksDistribution

java.lang.Object

org.apache.hadoop.hbase.HDFSBlocksDistribution

@InterfaceAudience.Private
public class HDFSBlocksDistribution
extends Object

Data structure to describe the distribution of HDFS blocks among hosts. Adding erroneous data will be ignored silently.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	HDFSBlocksDistribution.HostAndWeight Stores the hostname and weight for that hostname.

Field Summary

Fields

Modifier and Type	Field and Description
private Map<String,HDFSBlocksDistribution.HostAndWeight>	hostAndWeights
private long	uniqueBlocksTotalWeight

Constructor Summary

Constructors

Constructor and Description
HDFSBlocksDistribution() Constructor

Method Summary

Modifier and Type	Method and Description
void	add(HDFSBlocksDistribution otherBlocksDistribution) This will add the distribution from input to this object
private void	addHostAndBlockWeight(String host, long weight) add some weight to a specific host
void	addHostsAndBlockWeight(String[] hosts, long weight) add some weight to a list of hosts, update the value of unique block weight
private void	addUniqueWeight(long weight) add some weight to the total unique weight
float	getBlockLocalityIndex(String host) return the locality index of a given host
Map<String,HDFSBlocksDistribution.HostAndWeight>	getHostAndWeights()
List<String>	getTopHosts() return the sorted list of hosts in terms of their weights
HDFSBlocksDistribution.HostAndWeight[]	getTopHostsWithWeights() return the sorted list of hosts in terms of their weights
long	getUniqueBlocksTotalWeight()
long	getWeight(String host) return the weight for a specific host, that will be the total bytes of all blocks on the host
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

hostAndWeights

private Map<String,HDFSBlocksDistribution.HostAndWeight> hostAndWeights

uniqueBlocksTotalWeight

private long uniqueBlocksTotalWeight

Constructor Detail

HDFSBlocksDistribution

public HDFSBlocksDistribution()

Constructor

Method Detail

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

addHostsAndBlockWeight

public void addHostsAndBlockWeight(String[] hosts,
                                   long weight)

add some weight to a list of hosts, update the value of unique block weight

Parameters:

hosts - the list of the host

weight - the weight

addUniqueWeight

private void addUniqueWeight(long weight)

add some weight to the total unique weight

Parameters:

weight - the weight

addHostAndBlockWeight

private void addHostAndBlockWeight(String host,
                                   long weight)

add some weight to a specific host

Parameters:

host - the host name

weight - the weight

getHostAndWeights

public Map<String,HDFSBlocksDistribution.HostAndWeight> getHostAndWeights()

Returns:

the hosts and their weights

getWeight

public long getWeight(String host)

return the weight for a specific host, that will be the total bytes of all blocks on the host

Parameters:

host - the host name

Returns:

the weight of the given host

getUniqueBlocksTotalWeight

public long getUniqueBlocksTotalWeight()

Returns:

the sum of all unique blocks' weight

getBlockLocalityIndex

public float getBlockLocalityIndex(String host)

return the locality index of a given host

Parameters:

host - the host name

Returns:

the locality index of the given host

add

public void add(HDFSBlocksDistribution otherBlocksDistribution)

This will add the distribution from input to this object

Parameters:

otherBlocksDistribution - the other hdfs blocks distribution

getTopHosts

public List<String> getTopHosts()

return the sorted list of hosts in terms of their weights

getTopHostsWithWeights

public HDFSBlocksDistribution.HostAndWeight[] getTopHostsWithWeights()

return the sorted list of hosts in terms of their weights