/**
* 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.drill.exec.planner.fragment;
/**
* Describes an operator's endpoint assignment requirements. Ordering is from no assignment requirement to mandatory
* assignment requirements. Changes/new addition should keep the order of increasing restrictive assignment requirement.
*/
public enum DistributionAffinity {
/**
* No affinity to any endpoints. Operator can run on any endpoint.
*/
NONE(SoftAffinityFragmentParallelizer.INSTANCE),
/**
* Operator has soft distribution affinity to one or more endpoints. Operator performs better when fragments are
* assigned to the endpoints with affinity, but not a mandatory requirement.
*/
SOFT(SoftAffinityFragmentParallelizer.INSTANCE),
/**
* Hard distribution affinity to one or more endpoints. Fragments having the operator must be scheduled on the nodes
* with affinity.
*/
HARD(HardAffinityFragmentParallelizer.INSTANCE);
private final FragmentParallelizer fragmentParallelizer;
DistributionAffinity(final FragmentParallelizer fragmentParallelizer) {
this.fragmentParallelizer = fragmentParallelizer;
}
/**
* @return {@link FragmentParallelizer} implementation.
*/
public FragmentParallelizer getFragmentParallelizer() {
return fragmentParallelizer;
}
/**
* Is the current DistributionAffinity less restrictive than the given DistributionAffinity?
* @param distributionAffinity
* @return
*/
public boolean isLessRestrictiveThan(final DistributionAffinity distributionAffinity) {
return ordinal() < distributionAffinity.ordinal();
}
}