/*
* Copyright (c) 2008-2017, Hazelcast, Inc. All Rights Reserved.
*
* Licensed 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 com.hazelcast.cardinality;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.test.HazelcastParallelClassRunner;
import com.hazelcast.test.HazelcastTestSupport;
import com.hazelcast.test.TestHazelcastInstanceFactory;
import com.hazelcast.test.annotation.ParallelTest;
import com.hazelcast.test.annotation.QuickTest;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.junit.runner.RunWith;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicInteger;
import static org.junit.Assert.assertEquals;
@RunWith(HazelcastParallelClassRunner.class)
@Category({QuickTest.class, ParallelTest.class})
public class CardinalityEstimatorAdvancedTest extends HazelcastTestSupport {
@Test
public void testCardinalityEstimatorFailure() {
int k = 4;
TestHazelcastInstanceFactory nodeFactory = createHazelcastInstanceFactory(k + 1);
HazelcastInstance instance = nodeFactory.newHazelcastInstance();
String name = "testFailure";
CardinalityEstimator estimator = instance.getCardinalityEstimator(name);
estimator.add(1L);
for (int i = 0; i < k; i++) {
HazelcastInstance newInstance = nodeFactory.newHazelcastInstance();
waitAllForSafeState(instance, newInstance);
CardinalityEstimator newEstimator = newInstance.getCardinalityEstimator(name);
assertEquals((long) 1 + i, newEstimator.estimate());
newEstimator.add(String.valueOf(i + 1));
instance.shutdown();
instance = newInstance;
}
}
@Test
public void testCardinalityEstimatorFailure_whenSwitchedToDense() {
int k = 4;
int sparseLimit = 10000;
TestHazelcastInstanceFactory nodeFactory = createHazelcastInstanceFactory(k + 1);
HazelcastInstance instance = nodeFactory.newHazelcastInstance();
String name = "testFailure_whenSwitchedToDense";
CardinalityEstimator estimator = instance.getCardinalityEstimator(name);
for (int i = 0; i < sparseLimit; i++) {
estimator.add(String.valueOf(i + 1));
}
long estimateSoFar = estimator.estimate();
for (int i = 0; i < k; i++) {
HazelcastInstance newInstance = nodeFactory.newHazelcastInstance();
waitAllForSafeState(instance, newInstance);
CardinalityEstimator newEstimator = newInstance.getCardinalityEstimator(name);
assertEquals(estimateSoFar, newEstimator.estimate());
// Add numbers with huge gaps in between to guarantee change of est.
newEstimator.add(String.valueOf(1 << (14 + i)));
estimateSoFar = newEstimator.estimate();
instance.shutdown();
instance = newInstance;
}
}
@Test
public void testCardinalityEstimatorSpawnNodeInParallel() {
int total = 6;
int parallel = 2;
final TestHazelcastInstanceFactory nodeFactory = createHazelcastInstanceFactory(total + 1);
HazelcastInstance instance = nodeFactory.newHazelcastInstance();
final String name = "testSpawnNodeInParallel";
CardinalityEstimator estimator = instance.getCardinalityEstimator(name);
estimator.add(1L);
final ExecutorService ex = Executors.newFixedThreadPool(parallel);
try {
for (int i = 0; i < total / parallel; i++) {
final HazelcastInstance[] instances = new HazelcastInstance[parallel];
final CountDownLatch countDownLatch = new CountDownLatch(parallel);
final AtomicInteger counter = new AtomicInteger(0);
final AtomicInteger exceptionCount = new AtomicInteger(0);
for (int j = 0; j < parallel; j++) {
final int id = j;
ex.execute(new Runnable() {
public void run() {
try {
counter.incrementAndGet();
instances[id] = nodeFactory.newHazelcastInstance();
instances[id].getCardinalityEstimator(name)
.add(String.valueOf(counter.get()));
} catch (Exception e) {
exceptionCount.incrementAndGet();
e.printStackTrace();
} finally {
countDownLatch.countDown();
}
}
});
}
assertOpenEventually(countDownLatch);
// if there is an exception while incrementing in parallel threads, find number of exceptions
// and subtract the number from expectedValue.
final int thrownExceptionCount = exceptionCount.get();
final long expectedValue = (long) counter.get() - thrownExceptionCount;
CardinalityEstimator newEstimator = instance.getCardinalityEstimator(name);
assertEquals(expectedValue, newEstimator.estimate());
instance.shutdown();
instance = instances[0];
waitAllForSafeState(instances);
}
} finally {
ex.shutdownNow();
}
}
}