Package org.bstick12.jenkinsci.plugins.leastload

Class LeastLoadBalancer

java.lang.Object

hudson.model.LoadBalancer

org.bstick12.jenkinsci.plugins.leastload.LeastLoadBalancer

All Implemented Interfaces:

ExtensionPoint

public class LeastLoadBalancer
extends LoadBalancer

A LoadBalancer implementation that the leastload plugin uses to replace the default Jenkins LoadBalancer

The LeastLoadBalancer chooses Executors that have the least load. An Executor is defined as having the least load if it is idle or has the most available Executors

Only executor chunks that are clearly available (node non-null, not offline) are considered. The balancer tracks nodes that have not yet been assigned work this "round"; it assigns to a known-empty node uniquely. When all tracked nodes have been used, it re-checks Jenkins for currently available nodes (online, accepting tasks, with idle executors) and starts a new round. This spreads load and avoids multiple jobs piling on the same agent before queue maintenance runs again.

When least-load cannot produce a mapping, it returns null so the task remains in the queue for the next cycle. The fallback load balancer is used only when least-load is disabled for the job via LeastLoadDisabledProperty.

Author:

brendan.nolan@gmail.com

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	LeastLoadBalancer.ExecutorChunkComparator

Nested classes/interfaces inherited from interface hudson.ExtensionPoint

ExtensionPoint.LegacyInstancesAreScopedToHudson

Field Summary

Fields inherited from class hudson.model.LoadBalancer

CONSISTENT_HASH, DEFAULT

Constructor Summary

Constructors

Constructor	Description
LeastLoadBalancer(LoadBalancer fallback)	Create the LeastLoadBalancer with a fallback that will be used in case of any failures.

Method Summary

Modifier and Type	Method	Description
LoadBalancer	getFallBackLoadBalancer()	Retrieves the fallback LoadBalancer
MappingWorksheet.Mapping	map(Queue.Task task, MappingWorksheet ws)
static void	register()

Methods inherited from class hudson.model.LoadBalancer

sanitize

Methods inherited from class java.lang.Object

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

Constructor Details

LeastLoadBalancer

public LeastLoadBalancer(LoadBalancer fallback)

Create the LeastLoadBalancer with a fallback that will be used in case of any failures.

Parameters:

fallback - The LoadBalancer fallback to use in case of failure

Method Details

register

@Initializer
public static void register()

map

@CheckForNull
public MappingWorksheet.Mapping map(@NonNull
 Queue.Task task,
 MappingWorksheet ws)

Specified by:

map in class LoadBalancer

getFallBackLoadBalancer

public LoadBalancer getFallBackLoadBalancer()

Retrieves the fallback LoadBalancer

Returns:

- fallback LoadBalancer