i3wangyi commented on a change in pull request #463: Implement MaxCapacityUsageInstanceConstraint soft constraint URL: https://github.com/apache/helix/pull/463#discussion_r323978274
########## File path: helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/constraints/MaxCapacityUsageInstanceConstraint.java ########## @@ -0,0 +1,53 @@ +package org.apache.helix.controller.rebalancer.waged.constraints; + +/* + * 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. + */ + +import org.apache.helix.controller.rebalancer.waged.model.AssignableNode; +import org.apache.helix.controller.rebalancer.waged.model.AssignableReplica; +import org.apache.helix.controller.rebalancer.waged.model.ClusterContext; + +/** + * The constraint evaluates the score by checking the max used capacity key out of all the capacity + * keys. + * The higher the maximum usage value for the capacity key, the lower the score will be, implying + * that it is that much less desirable to assign anything on the given node. + * It is a greedy approach since it evaluates only on the most used capacity key. + */ +class MaxCapacityUsageInstanceConstraint extends SoftConstraint { + private static final float MIN_SCORE = 0; + private static final float MAX_SCORE = 1; + + MaxCapacityUsageInstanceConstraint() { + super(MAX_SCORE, MIN_SCORE); + } + + @Override + protected float getAssignmentScore(AssignableNode node, AssignableReplica replica, + ClusterContext clusterContext) { + float maxCapacityUsage = node.getHighestCapacityUtilization(); + return (1.0f - maxCapacityUsage) / 2; Review comment: It's simply the copy over from previous work. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@helix.apache.org For additional commands, e-mail: reviews-h...@helix.apache.org
