/**
* 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.hadoop.yarn.api.records;
import org.apache.hadoop.classification.InterfaceAudience.Public;
import org.apache.hadoop.classification.InterfaceStability.Evolving;
import org.apache.hadoop.classification.InterfaceStability.Stable;
import org.apache.hadoop.yarn.api.ApplicationMasterProtocol;
import org.apache.hadoop.yarn.util.Records;
/**
* <p><code>Resource</code> models a set of computer resources in the
* cluster.</p>
*
* <p>Currently it models both <em>memory</em> and <em>CPU</em>.</p>
*
* <p>The unit for memory is megabytes. CPU is modeled with virtual cores
* (vcores), a unit for expressing parallelism. A node's capacity should
* be configured with virtual cores equal to its number of physical cores. A
* container should be requested with the number of cores it can saturate, i.e.
* the average number of threads it expects to have runnable at a time.</p>
*
* <p>Virtual cores take integer values and thus currently CPU-scheduling is
* very coarse. A complementary axis for CPU requests that represents processing
* power will likely be added in the future to enable finer-grained resource
* configuration.</p>
*
* <p>Typically, applications request <code>Resource</code> of suitable
* capability to run their component tasks.</p>
*
* @see ResourceRequest
* @see ApplicationMasterProtocol#allocate(org.apache.hadoop.yarn.api.protocolrecords.AllocateRequest)
*/
@Public
@Stable
public abstract class Resource implements Comparable<Resource> {
@Public
@Stable
public static Resource newInstance(int memory, int vCores) {
Resource resource = Records.newRecord(Resource.class);
resource.setMemory(memory);
resource.setVirtualCores(vCores);
return resource;
}
/**
* Get <em>memory</em> of the resource.
* @return <em>memory</em> of the resource
*/
@Public
@Stable
public abstract int getMemory();
/**
* Set <em>memory</em> of the resource.
* @param memory <em>memory</em> of the resource
*/
@Public
@Stable
public abstract void setMemory(int memory);
/**
* Get <em>number of virtual cpu cores</em> of the resource.
*
* Virtual cores are a unit for expressing CPU parallelism. A node's capacity
* should be configured with virtual cores equal to its number of physical cores.
* A container should be requested with the number of cores it can saturate, i.e.
* the average number of threads it expects to have runnable at a time.
*
* @return <em>num of virtual cpu cores</em> of the resource
*/
@Public
@Evolving
public abstract int getVirtualCores();
/**
* Set <em>number of virtual cpu cores</em> of the resource.
*
* Virtual cores are a unit for expressing CPU parallelism. A node's capacity
* should be configured with virtual cores equal to its number of physical cores.
* A container should be requested with the number of cores it can saturate, i.e.
* the average number of threads it expects to have runnable at a time.
*
* @param vCores <em>number of virtual cpu cores</em> of the resource
*/
@Public
@Evolving
public abstract void setVirtualCores(int vCores);
@Override
public int hashCode() {
final int prime = 263167;
int result = 3571;
result = 939769357 + getMemory(); // prime * result = 939769357 initially
result = prime * result + getVirtualCores();
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (!(obj instanceof Resource))
return false;
Resource other = (Resource) obj;
if (getMemory() != other.getMemory() ||
getVirtualCores() != other.getVirtualCores()) {
return false;
}
return true;
}
@Override
public String toString() {
return "<memory:" + getMemory() + ", vCores:" + getVirtualCores() + ">";
}
}