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

Class SlowPeerTracker

java.lang.Object

org.apache.hadoop.hdfs.server.blockmanagement.SlowPeerTracker

Direct Known Subclasses:

SlowPeerDisabledTracker

@Private
@Unstable
public class SlowPeerTracker
extends java.lang.Object

This class aggregates information from SlowPeerReports received via heartbeats.

Field Summary

Fields

Modifier and Type	Field	Description
static org.slf4j.Logger	LOG

Constructor Summary

Constructors

Constructor	Description
SlowPeerTracker(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.util.Timer timer)

Method Summary

Modifier and Type	Method	Description
void	addReport(java.lang.String slowNode, java.lang.String reportingNode, org.apache.hadoop.hdfs.server.protocol.OutlierMetrics slowNodeMetrics)	Add a new report.
java.lang.String	getJson()	Retrieve all valid reports as a JSON string.
java.util.Map<java.lang.String,java.util.SortedSet<org.apache.hadoop.hdfs.server.blockmanagement.SlowPeerLatencyWithReportingNode>>	getReportsForAllDataNodes()	Retrieve all reports for all nodes.
java.util.Set<org.apache.hadoop.hdfs.server.blockmanagement.SlowPeerLatencyWithReportingNode>	getReportsForNode(java.lang.String slowNode)	Retrieve the non-expired reports that mark a given DataNode as slow.
java.util.List<java.lang.String>	getSlowNodes(int numNodes)	Returns all tracking slow peers.
boolean	isSlowPeerTrackerEnabled()	If SlowPeerTracker is enabled, return true, else returns false.
void	setMaxSlowPeersToReport(int maxSlowPeersToReport)

Methods inherited from class java.lang.Object

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

Field Detail

LOG

public static final org.slf4j.Logger LOG

Constructor Detail

SlowPeerTracker

public SlowPeerTracker(org.apache.hadoop.conf.Configuration conf,
                       org.apache.hadoop.util.Timer timer)

Method Detail

isSlowPeerTrackerEnabled

public boolean isSlowPeerTrackerEnabled()

If SlowPeerTracker is enabled, return true, else returns false.

Returns:

true if slow peer tracking is enabled, else false.

addReport

public void addReport(java.lang.String slowNode,
                      java.lang.String reportingNode,
                      org.apache.hadoop.hdfs.server.protocol.OutlierMetrics slowNodeMetrics)

Add a new report. DatanodeIds can be the DataNodeIds or addresses We don't care as long as the caller is consistent.

Parameters:

slowNode - DataNodeId of the peer suspected to be slow.

reportingNode - DataNodeId of the node reporting on its peer.

slowNodeMetrics - Aggregate latency metrics of slownode as reported by the reporting node.

getReportsForNode

public java.util.Set<org.apache.hadoop.hdfs.server.blockmanagement.SlowPeerLatencyWithReportingNode> getReportsForNode(java.lang.String slowNode)

Retrieve the non-expired reports that mark a given DataNode as slow. Stale reports are excluded.

Parameters:

slowNode - target node Id.

Returns:

set of reports which implicate the target node as being slow.

getReportsForAllDataNodes

public java.util.Map<java.lang.String,java.util.SortedSet<org.apache.hadoop.hdfs.server.blockmanagement.SlowPeerLatencyWithReportingNode>> getReportsForAllDataNodes()

Retrieve all reports for all nodes. Stale reports are excluded.

Returns:

map from SlowNodeId -> (set of nodes reporting peers).

getJson

public java.lang.String getJson()

Retrieve all valid reports as a JSON string.

Returns:

serialized representation of valid reports. null if serialization failed.

getSlowNodes

public java.util.List<java.lang.String> getSlowNodes(int numNodes)

Returns all tracking slow peers.

Parameters:

numNodes -

Returns:

setMaxSlowPeersToReport

public void setMaxSlowPeersToReport(int maxSlowPeersToReport)