opendaylight/md-sal/sal-distributed-eos/src/test/java/org/opendaylight/controller/cluster/entityownership/selectionstrategy/LeastLoadedCandidateSelectionStrategyTest.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.cluster.entityownership.selectionstrategy;
   9
  10 import static org.junit.Assert.assertEquals;
  11
  12 import java.util.ArrayList;
  13 import java.util.Collection;
  14 import java.util.Collections;
  15 import java.util.HashMap;
  16 import java.util.Map;
  17 import org.junit.Test;
  18
  19 public class LeastLoadedCandidateSelectionStrategyTest {
  20
  21     @Test
  22     public void testLeastLoadedStrategy() {
  23         LeastLoadedCandidateSelectionStrategy strategy = new LeastLoadedCandidateSelectionStrategy(
  24                 0L, Collections.<String, Long>emptyMap());
  25
  26         String owner = strategy.newOwner(null, prepareViableCandidates(3));
  27         assertEquals("member-1", owner);
  28
  29         Map<String, Long> localStatistics = strategy.getLocalStatistics();
  30         assertEquals(1L, (long) localStatistics.get("member-1"));
  31
  32         // member-2 has least load
  33         strategy = new LeastLoadedCandidateSelectionStrategy(0L, prepareStatistics(5,2,4));
  34         owner = strategy.newOwner(null, prepareViableCandidates(3));
  35         assertEquals("member-2", owner);
  36
  37         assertStatistics(strategy.getLocalStatistics(), 5,3,4);
  38
  39         // member-3 has least load
  40         strategy = new LeastLoadedCandidateSelectionStrategy(0L, prepareStatistics(5,7,4));
  41         owner = strategy.newOwner(null, prepareViableCandidates(3));
  42         assertEquals("member-3", owner);
  43
  44         assertStatistics(strategy.getLocalStatistics(), 5,7,5);
  45
  46         // member-1 has least load
  47         strategy = new LeastLoadedCandidateSelectionStrategy(0L, prepareStatistics(1,7,4));
  48         owner = strategy.newOwner(null, prepareViableCandidates(3));
  49         assertEquals("member-1", owner);
  50
  51         assertStatistics(strategy.getLocalStatistics(), 2,7,4);
  52
  53         // Let member-3 become the owner
  54         strategy = new LeastLoadedCandidateSelectionStrategy(0L, prepareStatistics(3,3,0));
  55         owner = strategy.newOwner(null, prepareViableCandidates(3));
  56         assertEquals("member-3", owner);
  57
  58         assertStatistics(strategy.getLocalStatistics(), 3,3,1);
  59
  60         // member-3 is no longer viable so choose a new owner
  61         owner = strategy.newOwner("member-3", prepareViableCandidates(2));
  62         assertEquals("member-1", owner);
  63
  64         assertStatistics(strategy.getLocalStatistics(), 4,3,0);
  65
  66     }
  67
  68     private static Map<String, Long> prepareStatistics(long... count) {
  69         Map<String, Long> statistics = new HashMap<>();
  70         for (int i = 0; i < count.length; i++) {
  71             statistics.put("member-" + (i + 1), count[i]);
  72         }
  73         return statistics;
  74     }
  75
  76     private static Collection<String> prepareViableCandidates(int count) {
  77         Collection<String> viableCandidates = new ArrayList<>();
  78         for (int i = 0; i < count; i++) {
  79             viableCandidates.add("member-" + (i + 1));
  80         }
  81         return viableCandidates;
  82     }
  83
  84     private static void assertStatistics(Map<String, Long> statistics, long... count) {
  85         for (int i = 0; i < count.length; i++) {
  86             assertEquals(count[i], (long) statistics.get("member-" + (i + 1)));
  87         }
  88     }
  89 }