Package org.apache.hadoop.hdfs.server.diskbalancer.datamodel

Class DiskBalancerDataNode

java.lang.Object

org.apache.hadoop.hdfs.server.diskbalancer.datamodel.DiskBalancerDataNode

All Implemented Interfaces:

java.lang.Comparable<DiskBalancerDataNode>

public class DiskBalancerDataNode
extends java.lang.Object
implements java.lang.Comparable<DiskBalancerDataNode>

DiskBalancerDataNode represents a DataNode that exists in the cluster. It also contains a metric called nodeDataDensity which allows us to compare between a set of Nodes.

Constructor Summary

Constructors

Constructor	Description
DiskBalancerDataNode()	Constructs an Empty Data Node.
DiskBalancerDataNode(java.lang.String dataNodeID)	Constructs a DataNode.

Method Summary

Modifier and Type	Method	Description
void	addVolume(DiskBalancerVolume volume)	Adds a volume to the DataNode.
int	compareTo(DiskBalancerDataNode that)	Compares this object with the specified object for order.
void	computeNodeDensity()	Computes nodes data density.
boolean	equals(java.lang.Object obj)	Indicates whether some other object is "equal to" this one.
java.lang.String	getDataNodeIP()	Returns the IP address of this Node.
java.lang.String	getDataNodeName()	Get DataNode DNS name.
int	getDataNodePort()	Returns the Port of this DataNode.
java.lang.String	getDataNodeUUID()	Returns datanode ID.
double	getNodeDataDensity()	Returns NodeDataDensity Metric.
int	getVolumeCount()	Returns how many volumes are in the DataNode.
java.util.Map<java.lang.String,DiskBalancerVolumeSet>	getVolumeSets()	Returns the Volume sets on this node.
int	hashCode()	Returns a hash code value for the object.
boolean	isBalancingNeeded(double threshold)	Computes if this node needs balancing at all.
void	setDataNodeIP(java.lang.String ipaddress)	Sets the IP address of this Node.
void	setDataNodeName(java.lang.String name)	Sets node's DNS name.
void	setDataNodePort(int port)	Sets the DataNode Port number.
void	setDataNodeUUID(java.lang.String nodeID)	Sets Datanode UUID.

Methods inherited from class java.lang.Object

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

Constructor Detail

DiskBalancerDataNode

public DiskBalancerDataNode()

Constructs an Empty Data Node.

DiskBalancerDataNode

public DiskBalancerDataNode(java.lang.String dataNodeID)

Constructs a DataNode.

Parameters:

dataNodeID - - Node ID

Method Detail

getDataNodeIP

public java.lang.String getDataNodeIP()

Returns the IP address of this Node.

Returns:

IP Address string

setDataNodeIP

public void setDataNodeIP(java.lang.String ipaddress)

Sets the IP address of this Node.

Parameters:

ipaddress - - IP Address

getDataNodePort

public int getDataNodePort()

Returns the Port of this DataNode.

Returns:

Port Number

setDataNodePort

public void setDataNodePort(int port)

Sets the DataNode Port number.

Parameters:

port - - Datanode Port Number

getDataNodeName

public java.lang.String getDataNodeName()

Get DataNode DNS name.

Returns:

name of the node

setDataNodeName

public void setDataNodeName(java.lang.String name)

Sets node's DNS name.

Parameters:

name - - Data node name

getVolumeSets

public java.util.Map<java.lang.String,DiskBalancerVolumeSet> getVolumeSets()

Returns the Volume sets on this node.

Returns:

a Map of VolumeSets

getDataNodeUUID

public java.lang.String getDataNodeUUID()

Returns datanode ID.

setDataNodeUUID

public void setDataNodeUUID(java.lang.String nodeID)

Sets Datanode UUID.

Parameters:

nodeID - - Node ID.

equals

public boolean equals(java.lang.Object obj)

Indicates whether some other object is "equal to" this one.

Overrides:

equals in class java.lang.Object

compareTo

public int compareTo(DiskBalancerDataNode that)

Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Specified by:

compareTo in interface java.lang.Comparable<DiskBalancerDataNode>

Parameters:

that - the object to be compared.

Returns:

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Throws:

java.lang.NullPointerException - if the specified object is null

java.lang.ClassCastException - if the specified object's type prevents it from being compared to this object.

hashCode

public int hashCode()

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

Overrides:

hashCode in class java.lang.Object

getNodeDataDensity

public double getNodeDataDensity()

Returns NodeDataDensity Metric.

Returns:

float

computeNodeDensity

public void computeNodeDensity()

Computes nodes data density. This metric allows us to compare different nodes and how well the data is spread across a set of volumes inside the node.

isBalancingNeeded

public boolean isBalancingNeeded(double threshold)

Computes if this node needs balancing at all.

Parameters:

threshold - - Percentage

Returns:

true or false

addVolume

public void addVolume(DiskBalancerVolume volume)
               throws java.lang.Exception

Adds a volume to the DataNode. It is assumed that we have one thread per node hence this call is not synchronised neither is the map is protected.

Parameters:

volume - - volume

Throws:

java.lang.Exception

getVolumeCount

public int getVolumeCount()

Returns how many volumes are in the DataNode.

Returns:

int