org.apache.storm.scheduler.resource.strategies.scheduling

Interface IStrategy

All Known Implementing Classes:

BaseResourceAwareStrategy, ConstraintSolverStrategy, DefaultResourceAwareStrategy, DefaultResourceAwareStrategyOld, GenericResourceAwareStrategy, GenericResourceAwareStrategyOld, RoundRobinResourceAwareStrategy

public interface IStrategy

An interface to for implementing different scheduling strategies for the resource aware scheduling. Scheduler should call prepare(Map) followed by schedule(Cluster, TopologyDetails).

A fully functioning implementation is in the abstract class BaseResourceAwareStrategy. Subclasses classes should extend BaseResourceAwareStrategy.BaseResourceAwareStrategy() in their constructors (as in GenericResourceAwareStrategy, DefaultResourceAwareStrategy and ConstraintSolverStrategy).

Method Summary

Modifier and Type	Method and Description
void	prepare(Map<String,Object> config) Prepare the Strategy for scheduling.
SchedulingResult	schedule(Cluster schedulingState, TopologyDetails td) This method is invoked to calculate a scheduling for topology td.

Method Detail

prepare

void prepare(Map<String,Object> config)

Prepare the Strategy for scheduling.

Parameters:

config - the cluster configuration

schedule

SchedulingResult schedule(Cluster schedulingState,
                          TopologyDetails td)

This method is invoked to calculate a scheduling for topology td. Cluster will reject any changes that are not for the given topology. Any changes made to the cluster will be committed if the scheduling is successful.

NOTE: scheduling occurs as a runnable in an interruptable thread. Scheduling should consider being interrupted if long running.

Parameters:

schedulingState - the current state of the cluster

td - the topology to schedule for

Returns:

returns a SchedulingResult object containing SchedulingStatus object to indicate whether scheduling is successful.