org.apache.myriad.scheduler.yarn.MyriadCapacityScheduler.java Source code

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Here is the source code for org.apache.myriad.scheduler.yarn.MyriadCapacityScheduler.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * 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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.myriad.scheduler.yarn;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.yarn.server.resourcemanager.RMContext;
import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNodeEvent;
import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNodeEventType;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler;
import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.SchedulerEvent;
import org.apache.myriad.scheduler.yarn.interceptor.CompositeInterceptor;
import org.apache.myriad.scheduler.yarn.interceptor.YarnSchedulerInterceptor;

/**
 * {@link MyriadCapacityScheduler} just extends YARN's {@link CapacityScheduler} and
 * allows some of the {@link CapacityScheduler} methods to be intercepted
 * via the {@link YarnSchedulerInterceptor} interface.
 */
public class MyriadCapacityScheduler extends CapacityScheduler {
    private Configuration conf;

    private RMContext rmContext;
    private YarnSchedulerInterceptor yarnSchedulerInterceptor;
    private RMNodeEventHandler rmNodeEventHandler;

    public MyriadCapacityScheduler() {
        super();
    }

    /**
     * Register an event handler that receives {@link RMNodeEvent} events.
     * This event handler is registered ahead of RM's own event handler for RMNodeEvents.
     * For e.g. myriad can inspect a node's HB (RMNodeStatusEvent) before the HB is handled by
     * RM and the scheduler.
     *
     * @param rmContext
     */
    @Override
    public synchronized void setRMContext(RMContext rmContext) {
        this.rmContext = rmContext;
        this.yarnSchedulerInterceptor = new CompositeInterceptor();
        rmNodeEventHandler = new RMNodeEventHandler(yarnSchedulerInterceptor, rmContext);
        rmContext.getDispatcher().register(RMNodeEventType.class, rmNodeEventHandler);
        super.setRMContext(rmContext);
    }

    /**
     * ******** Methods overridden from YARN {@link CapacityScheduler}  *********************
     */

    @Override
    public synchronized void serviceInit(Configuration conf) throws Exception {
        this.conf = conf;
        super.serviceInit(conf);
    }

    @Override
    public synchronized void serviceStart() throws Exception {
        this.yarnSchedulerInterceptor.init(conf, this, rmContext);
        super.serviceStart();
    }

    @Override
    public synchronized void handle(SchedulerEvent event) {
        this.yarnSchedulerInterceptor.beforeSchedulerEventHandled(event);
        super.handle(event);
        this.yarnSchedulerInterceptor.afterSchedulerEventHandled(event);
    }
}