org.apache.samza.job.yarn

Class YarnFaultDomainManager

java.lang.Object

org.apache.samza.job.yarn.YarnFaultDomainManager

All Implemented Interfaces:

org.apache.samza.clustermanager.FaultDomainManager

public class YarnFaultDomainManager
extends java.lang.Object
implements org.apache.samza.clustermanager.FaultDomainManager

This class functionality works with the assumption that the job.standbytasks.replication.factor is 2. For values greater than 2, it is possible that the standby containers could be on the same rack as the active, or the already existing standby racks.

Constructor Summary

Constructors

Constructor and Description
YarnFaultDomainManager(org.apache.samza.metrics.MetricsRegistry metricsRegistry)

Method Summary

Modifier and Type	Method and Description
java.util.Set<org.apache.samza.clustermanager.FaultDomain>	getAllFaultDomains() This method returns all the last cached rack values in a cluster, for all hosts that are healthy, up and running.
java.util.Set<org.apache.samza.clustermanager.FaultDomain>	getFaultDomainsForHost(java.lang.String host) This method returns the rack a particular host resides on based on the internal cache.
boolean	hasSameFaultDomains(java.lang.String host1, java.lang.String host2) This method checks if the two hostnames provided reside on the same rack.

Methods inherited from class java.lang.Object

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

Constructor Detail

YarnFaultDomainManager

public YarnFaultDomainManager(org.apache.samza.metrics.MetricsRegistry metricsRegistry)

Method Detail

getAllFaultDomains

public java.util.Set<org.apache.samza.clustermanager.FaultDomain> getAllFaultDomains()

This method returns all the last cached rack values in a cluster, for all hosts that are healthy, up and running.

Specified by:

getAllFaultDomains in interface org.apache.samza.clustermanager.FaultDomainManager

Returns:

a set of FaultDomains

getFaultDomainsForHost

public java.util.Set<org.apache.samza.clustermanager.FaultDomain> getFaultDomainsForHost(java.lang.String host)

This method returns the rack a particular host resides on based on the internal cache. In case the rack of a host does not exist in this cache, we update the cache by computing the host to rack map again using Yarn.

Specified by:

getFaultDomainsForHost in interface org.apache.samza.clustermanager.FaultDomainManager

Parameters:

host - the host

Returns:

the FaultDomain

hasSameFaultDomains

public boolean hasSameFaultDomains(java.lang.String host1,
                                   java.lang.String host2)

This method checks if the two hostnames provided reside on the same rack.

Specified by:

hasSameFaultDomains in interface org.apache.samza.clustermanager.FaultDomainManager

Parameters:

host1 - hostname

host2 - hostname

Returns:

true if the hosts exist on the same rack