io.druid.indexing.overlord.autoscaling.ResourceManagementStrategy Maven / Gradle / Ivy
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* Licensed to Metamarkets Group Inc. (Metamarkets) under one
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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*/
package io.druid.indexing.overlord.autoscaling;
import io.druid.indexing.overlord.TaskRunner;
/**
* The ResourceManagementStrategy decides if worker nodes should be provisioned or determined
* based on the available tasks in the system and the state of the workers in the system.
* In general, the resource management is tied to the runner.
*/
public interface ResourceManagementStrategy
{
/**
* Equivalent to start() but requires a specific runner instance which holds state of interest.
* This method is intended to be called from the TaskRunner's lifecycle
*
* @param runner The TaskRunner state holder this strategy should use during execution
*/
void startManagement(T runner);
/**
* Equivalent to stop()
* Should be called from TaskRunner's lifecycle
*/
void stopManagement();
/**
* Get any interesting stats related to scaling
*
* @return The ScalingStats or `null` if nothing of interest
*/
ScalingStats getStats();
}