eu.stratosphere.pact.runtime.task.ReduceTaskTest.java Source code

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/***********************************************************************************************************************
 * Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
 *
 * 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 eu.stratosphere.pact.runtime.task;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;

import junit.framework.Assert;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.junit.Test;

import eu.stratosphere.api.common.functions.GenericGroupReduce;
import eu.stratosphere.api.java.record.functions.ReduceFunction;
import eu.stratosphere.api.java.record.operators.ReduceOperator.Combinable;
import eu.stratosphere.api.java.typeutils.runtime.record.RecordComparator;
import eu.stratosphere.api.java.typeutils.runtime.record.RecordSerializerFactory;
import eu.stratosphere.pact.runtime.sort.CombiningUnilateralSortMerger;
import eu.stratosphere.pact.runtime.test.util.DelayingInfinitiveInputIterator;
import eu.stratosphere.pact.runtime.test.util.DriverTestBase;
import eu.stratosphere.pact.runtime.test.util.ExpectedTestException;
import eu.stratosphere.pact.runtime.test.util.NirvanaOutputList;
import eu.stratosphere.pact.runtime.test.util.TaskCancelThread;
import eu.stratosphere.pact.runtime.test.util.UniformRecordGenerator;
import eu.stratosphere.types.IntValue;
import eu.stratosphere.types.Key;
import eu.stratosphere.types.Record;
import eu.stratosphere.util.Collector;

public class ReduceTaskTest extends DriverTestBase<GenericGroupReduce<Record, Record>> {
    private static final Log LOG = LogFactory.getLog(ReduceTaskTest.class);

    @SuppressWarnings("unchecked")
    private final RecordComparator comparator = new RecordComparator(new int[] { 0 },
            (Class<? extends Key<?>>[]) new Class[] { IntValue.class });

    private final List<Record> outList = new ArrayList<Record>();

    public ReduceTaskTest() {
        super(0, 1, 3 * 1024 * 1024);
    }

    @Test
    public void testReduceTaskWithSortingInput() {
        final int keyCnt = 100;
        final int valCnt = 20;

        addInputComparator(this.comparator);
        setOutput(this.outList);
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        try {
            addInputSorted(new UniformRecordGenerator(keyCnt, valCnt, false), this.comparator.duplicate());

            GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

            testDriver(testTask, MockReduceStub.class);
        } catch (Exception e) {
            LOG.debug(e);
            Assert.fail("Exception in Test.");
        }

        Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt,
                this.outList.size() == keyCnt);

        for (Record record : this.outList) {
            Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == valCnt
                    - record.getField(0, IntValue.class).getValue());
        }

        this.outList.clear();
    }

    @Test
    public void testReduceTaskOnPreSortedInput() {
        final int keyCnt = 100;
        final int valCnt = 20;

        addInput(new UniformRecordGenerator(keyCnt, valCnt, true));
        addInputComparator(this.comparator);
        setOutput(this.outList);
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

        try {
            testDriver(testTask, MockReduceStub.class);
        } catch (Exception e) {
            LOG.debug(e);
            Assert.fail("Invoke method caused exception.");
        }

        Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt,
                this.outList.size() == keyCnt);

        for (Record record : this.outList) {
            Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == valCnt
                    - record.getField(0, IntValue.class).getValue());
        }

        this.outList.clear();
    }

    @Test
    public void testCombiningReduceTask() {
        final int keyCnt = 100;
        final int valCnt = 20;

        addInputComparator(this.comparator);
        setOutput(this.outList);
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        CombiningUnilateralSortMerger<Record> sorter = null;
        try {
            sorter = new CombiningUnilateralSortMerger<Record>(new MockCombiningReduceStub(), getMemoryManager(),
                    getIOManager(), new UniformRecordGenerator(keyCnt, valCnt, false), getOwningNepheleTask(),
                    RecordSerializerFactory.get(), this.comparator.duplicate(), this.perSortMem, 4, 0.8f);
            addInput(sorter.getIterator());

            GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

            testDriver(testTask, MockCombiningReduceStub.class);
        } catch (Exception e) {
            LOG.debug(e);
            Assert.fail("Invoke method caused exception.");
        } finally {
            if (sorter != null) {
                sorter.close();
            }
        }

        int expSum = 0;
        for (int i = 1; i < valCnt; i++) {
            expSum += i;
        }

        Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt,
                this.outList.size() == keyCnt);

        for (Record record : this.outList) {
            Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == expSum
                    - record.getField(0, IntValue.class).getValue());
        }

        this.outList.clear();

    }

    @Test
    public void testFailingReduceTask() {
        final int keyCnt = 100;
        final int valCnt = 20;

        addInput(new UniformRecordGenerator(keyCnt, valCnt, true));
        addInputComparator(this.comparator);
        setOutput(this.outList);
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

        try {
            testDriver(testTask, MockFailingReduceStub.class);
            Assert.fail("Function exception was not forwarded.");
        } catch (ExpectedTestException eetex) {
            // Good!
        } catch (Exception e) {
            LOG.debug(e);
            Assert.fail("Test caused exception.");
        }

        this.outList.clear();
    }

    @Test
    public void testCancelReduceTaskWhileSorting() {
        addInputComparator(this.comparator);
        setOutput(new NirvanaOutputList());
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        final GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

        try {
            addInputSorted(new DelayingInfinitiveInputIterator(100), this.comparator.duplicate());
        } catch (Exception e) {
            e.printStackTrace();
            Assert.fail();
        }

        final AtomicBoolean success = new AtomicBoolean(false);

        Thread taskRunner = new Thread() {
            @Override
            public void run() {
                try {
                    testDriver(testTask, MockReduceStub.class);
                    success.set(true);
                } catch (Exception ie) {
                    ie.printStackTrace();
                }
            }
        };
        taskRunner.start();

        TaskCancelThread tct = new TaskCancelThread(1, taskRunner, this);
        tct.start();

        try {
            tct.join();
            taskRunner.join();
        } catch (InterruptedException ie) {
            Assert.fail("Joining threads failed");
        }

        Assert.assertTrue("Test threw an exception even though it was properly canceled.", success.get());
    }

    @Test
    public void testCancelReduceTaskWhileReducing() {

        final int keyCnt = 1000;
        final int valCnt = 2;

        addInput(new UniformRecordGenerator(keyCnt, valCnt, true));
        addInputComparator(this.comparator);
        setOutput(new NirvanaOutputList());
        getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE);

        final GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>();

        final AtomicBoolean success = new AtomicBoolean(false);

        Thread taskRunner = new Thread() {
            @Override
            public void run() {
                try {
                    testDriver(testTask, MockDelayingReduceStub.class);
                    success.set(true);
                } catch (Exception ie) {
                    ie.printStackTrace();
                }
            }
        };
        taskRunner.start();

        TaskCancelThread tct = new TaskCancelThread(2, taskRunner, this);
        tct.start();

        try {
            tct.join();
            taskRunner.join();
        } catch (InterruptedException ie) {
            Assert.fail("Joining threads failed");
        }

    }

    public static class MockReduceStub extends ReduceFunction {
        private static final long serialVersionUID = 1L;

        private final IntValue key = new IntValue();
        private final IntValue value = new IntValue();

        @Override
        public void reduce(Iterator<Record> records, Collector<Record> out) throws Exception {
            Record element = null;
            int cnt = 0;
            while (records.hasNext()) {
                element = records.next();
                cnt++;
            }
            element.getField(0, this.key);
            this.value.setValue(cnt - this.key.getValue());
            element.setField(1, this.value);
            out.collect(element);
        }
    }

    @Combinable
    public static class MockCombiningReduceStub extends ReduceFunction {
        private static final long serialVersionUID = 1L;

        private final IntValue key = new IntValue();
        private final IntValue value = new IntValue();
        private final IntValue combineValue = new IntValue();

        @Override
        public void reduce(Iterator<Record> records, Collector<Record> out) throws Exception {
            Record element = null;
            int sum = 0;
            while (records.hasNext()) {
                element = records.next();
                element.getField(1, this.value);

                sum += this.value.getValue();
            }
            element.getField(0, this.key);
            this.value.setValue(sum - this.key.getValue());
            element.setField(1, this.value);
            out.collect(element);
        }

        @Override
        public void combine(Iterator<Record> records, Collector<Record> out) throws Exception {
            Record element = null;
            int sum = 0;
            while (records.hasNext()) {
                element = records.next();
                element.getField(1, this.combineValue);

                sum += this.combineValue.getValue();
            }

            this.combineValue.setValue(sum);
            element.setField(1, this.combineValue);
            out.collect(element);
        }

    }

    public static class MockFailingReduceStub extends ReduceFunction {
        private static final long serialVersionUID = 1L;

        private int cnt = 0;

        private final IntValue key = new IntValue();
        private final IntValue value = new IntValue();

        @Override
        public void reduce(Iterator<Record> records, Collector<Record> out) throws Exception {
            Record element = null;
            int valCnt = 0;
            while (records.hasNext()) {
                element = records.next();
                valCnt++;
            }

            if (++this.cnt >= 10) {
                throw new ExpectedTestException();
            }

            element.getField(0, this.key);
            this.value.setValue(valCnt - this.key.getValue());
            element.setField(1, this.value);
            out.collect(element);
        }
    }

    public static class MockDelayingReduceStub extends ReduceFunction {
        private static final long serialVersionUID = 1L;

        @Override
        public void reduce(Iterator<Record> records, Collector<Record> out) {
            while (records.hasNext()) {
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                }
                records.next();
            }
        }
    }
}