slider-core/src/main/java/org/apache/slider/server/appmaster/state/AbstractClusterServices.java

/*
 * 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
 *
 *     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 "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.slider.server.appmaster.state;

import com.google.common.base.Preconditions;
import org.apache.hadoop.yarn.api.records.Resource;
import org.apache.hadoop.yarn.util.resource.DefaultResourceCalculator;

/**
 * Cluster services offered by the YARN infrastructure.
 */
public abstract class AbstractClusterServices {

  private final DefaultResourceCalculator
      defaultResourceCalculator = new DefaultResourceCalculator();

  /**
   * Create a resource for requests
   * @return a resource which can be built up.
   */
  public abstract Resource newResource();

  public abstract Resource newResource(int memory, int cores);

  /**
   * Normalise memory, CPU and other resources according to the YARN AM-supplied
   * values and the resource calculator in use (currently hard-coded to the
   * {@link DefaultResourceCalculator}.
   * Those resources which aren't normalized (currently: CPU) are left
   * as is.
   * @param resource resource requirements of a role
   * @param minR minimum values of this queue
   * @param maxR max values of this queue
   * @return a normalized value.
   */
  public Resource normalize(Resource resource, Resource minR, Resource maxR) {
    Preconditions.checkArgument(resource != null, "null resource");
    Preconditions.checkArgument(minR != null, "null minR");
    Preconditions.checkArgument(maxR != null, "null maxR");

    Resource normalize = defaultResourceCalculator.normalize(resource, minR,
        maxR, minR);
    return newResource(normalize.getMemory(), resource.getVirtualCores());
  }
}