pinot-core/src/test/java/org/apache/pinot/core/operator/combine/CombineSlowOperatorsTest.java - pinot - Git at Google

 /**
  * 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.
  */
 package org.apache.pinot.core.operator.combine;

 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeoutException;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Supplier;
 import org.apache.pinot.common.response.ProcessingException;
 import org.apache.pinot.core.common.Block;
 import org.apache.pinot.core.common.Operator;
 import org.apache.pinot.core.operator.BaseOperator;
 import org.apache.pinot.core.operator.ExecutionStatistics;
 import org.apache.pinot.core.operator.blocks.results.BaseResultsBlock;
 import org.apache.pinot.core.query.request.context.QueryContext;
 import org.apache.pinot.core.query.request.context.utils.QueryContextConverterUtils;
 import org.apache.pinot.segment.spi.IndexSegment;
 import org.apache.pinot.segment.spi.datasource.DataSource;
 import org.apache.pinot.segment.spi.datasource.DataSourceMetadata;
 import org.apache.pinot.spi.exception.EarlyTerminationException;
 import org.apache.pinot.spi.exception.QueryCancelledException;
 import org.apache.pinot.util.TestUtils;
 import org.testng.Assert;
 import org.testng.annotations.AfterClass;
 import org.testng.annotations.BeforeClass;
 import org.testng.annotations.Test;

 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 import static org.testng.Assert.assertEquals;
 import static org.testng.Assert.assertFalse;
 import static org.testng.Assert.assertNotNull;
 import static org.testng.Assert.assertTrue;


 /**
  * This test mimic the behavior of combining slow operators, where operation is not done by the timeout. When the
  * combine operator returns, test whether the slow operators are properly interrupted, and if all the slow operators are
  * not running in order to safely release the segment references.
  */
 @SuppressWarnings("rawtypes")
 public class CombineSlowOperatorsTest {
   private static final int NUM_OPERATORS = 10;
   private static final int NUM_THREADS = 2;
   private static final long TIMEOUT_MS = 100L;

   private ExecutorService _executorService;

   @BeforeClass
   public void setUp() {
     _executorService = Executors.newFixedThreadPool(NUM_THREADS);
   }

   @Test
   public void testSelectionOnlyCombineOperator() {
     List<Operator> operators = getOperators();
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable");
     queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
     SelectionOnlyCombineOperator combineOperator =
         new SelectionOnlyCombineOperator(operators, queryContext, _executorService);
     testCombineOperator(operators, combineOperator);
   }

   // NOTE: Skip the test for SelectionOrderByCombineOperator because it requires SelectionOrderByOperator for the early
   //       termination optimization.

   @Test
   public void testAggregationOnlyCombineOperator() {
     List<Operator> operators = getOperators();
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable");
     queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
     AggregationCombineOperator combineOperator =
         new AggregationCombineOperator(operators, queryContext, _executorService);
     testCombineOperator(operators, combineOperator);
   }

   @Test
   public void testGroupByOrderByCombineOperator() {
     List<Operator> operators = getOperators();
     QueryContext queryContext =
         QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable GROUP BY column");
     queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
     GroupByCombineOperator combineOperator = new GroupByCombineOperator(operators, queryContext, _executorService);
     testCombineOperator(operators, combineOperator);
   }

   @Test
   public void testCancelSelectionOnlyCombineOperator() {
     // Just need to wait for one operator to start running.
     CountDownLatch ready = new CountDownLatch(1);
     List<Operator> operators = getOperators(ready, null);
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable");
     queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
     SelectionOnlyCombineOperator combineOperator =
         new SelectionOnlyCombineOperator(operators, queryContext, _executorService);
     testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
   }

   @Test
   public void testCancelSelectionOrderByCombineOperator() {
     CountDownLatch ready = new CountDownLatch(1);
     List<Operator> operators = getOperators(ready, null);
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable ORDER BY column");
     queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
     SelectionOrderByCombineOperator combineOperator =
         new SelectionOrderByCombineOperator(operators, queryContext, _executorService);
     testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
   }

   @Test
   public void testCancelMinMaxValueBasedSelectionOrderByCombineOperator() {
     CountDownLatch ready = new CountDownLatch(1);
     List<Operator> operators = getOperators(ready, () -> {
       IndexSegment seg = mock(IndexSegment.class);
       DataSource ds = mock(DataSource.class);
       DataSourceMetadata dsmd = mock(DataSourceMetadata.class);
       when(dsmd.getMinValue()).thenReturn(100L);
       when(dsmd.getMaxValue()).thenReturn(200L);
       when(seg.getDataSource(anyString())).thenReturn(ds);
       when(ds.getDataSourceMetadata()).thenReturn(dsmd);
       return seg;
     });
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable ORDER BY column");
     queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
     SelectionOrderByCombineOperator combineOperator =
         new SelectionOrderByCombineOperator(operators, queryContext, _executorService);
     testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
   }

   @Test
   public void testCancelAggregationOnlyCombineOperator() {
     CountDownLatch ready = new CountDownLatch(1);
     List<Operator> operators = getOperators(ready, null);
     QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable");
     queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
     AggregationCombineOperator combineOperator =
         new AggregationCombineOperator(operators, queryContext, _executorService);
     testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
   }

   @Test
   public void testCancelGroupByOrderByCombineOperator() {
     CountDownLatch ready = new CountDownLatch(1);
     List<Operator> operators = getOperators(ready, null);
     QueryContext queryContext =
         QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable GROUP BY column");
     queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
     GroupByCombineOperator combineOperator = new GroupByCombineOperator(operators, queryContext, _executorService);
     testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
   }

   private void testCancelCombineOperator(BaseCombineOperator combineOperator, CountDownLatch ready, String errMsg) {
     AtomicReference<Exception> exp = new AtomicReference<>();
     ExecutorService combineExecutor = Executors.newSingleThreadExecutor();
     try {
       Future<?> future = combineExecutor.submit(() -> {
         try {
           return combineOperator.nextBlock();
         } catch (Exception e) {
           exp.set(e);
           throw e;
         }
       });
       ready.await();
       // At this point, the combineOperator is or will be waiting on future.get() for all sub operators, and the
       // waiting can be cancelled as below.
       future.cancel(true);
     } catch (Exception e) {
       Assert.fail();
     } finally {
       combineExecutor.shutdownNow();
     }
     TestUtils.waitForCondition((aVoid) -> exp.get() instanceof QueryCancelledException, 10_000,
         "Should have been cancelled");
     assertEquals(exp.get().getMessage(), errMsg);
   }

   /**
    * NOTE: It is hard to test the logger behavior, but only one error message about the query timeout should be logged
    *       for each query.
    */
   private void testCombineOperator(List<Operator> operators, BaseOperator combineOperator) {
     BaseResultsBlock intermediateResultsBlock = (BaseResultsBlock) combineOperator.nextBlock();
     List<ProcessingException> processingExceptions = intermediateResultsBlock.getProcessingExceptions();
     assertNotNull(processingExceptions);
     assertEquals(processingExceptions.size(), 1);
     assertTrue(processingExceptions.get(0).getMessage().contains(TimeoutException.class.getName()));

     // When the CombineOperator returns, all operators should be either not scheduled or interrupted, and no operator
     // should be running so that the segment references can be safely released
     for (Operator operator : operators) {
       SlowOperator slowOperator = (SlowOperator) operator;
       assertFalse(slowOperator._operationInProgress.get());
       assertFalse(slowOperator._notInterrupted.get());
     }
   }

   @AfterClass
   public void tearDown() {
     _executorService.shutdown();
   }

   private List<Operator> getOperators() {
     return getOperators(null, null);
   }

   private List<Operator> getOperators(CountDownLatch ready, Supplier<IndexSegment> segmentSupplier) {
     List<Operator> operators = new ArrayList<>(NUM_OPERATORS);
     for (int i = 0; i < NUM_OPERATORS; i++) {
       operators.add(new SlowOperator(ready, segmentSupplier));
     }
     return operators;
   }

   private static class SlowOperator extends BaseOperator {
     private static final String EXPLAIN_NAME = "SLOW";

     final AtomicBoolean _operationInProgress = new AtomicBoolean();
     final AtomicBoolean _notInterrupted = new AtomicBoolean();
     private final CountDownLatch _ready;
     private final Supplier<IndexSegment> _segmentSupplier;

     public SlowOperator(CountDownLatch ready, Supplier<IndexSegment> segmentSupplier) {
       _ready = ready;
       _segmentSupplier = segmentSupplier;
     }

     @Override
     protected Block getNextBlock() {
       _operationInProgress.set(true);
       if (_ready != null) {
         _ready.countDown();
       }
       try {
         Thread.sleep(3_600_000L);
       } catch (InterruptedException e) {
         // Thread should be interrupted for early-termination
         throw new EarlyTerminationException();
       } finally {
         // Wait for 100 milliseconds before marking the operation done
         try {
           Thread.sleep(100L);
           _operationInProgress.set(false);
         } catch (InterruptedException e) {
           // Thread should not be interrupted again, and we should be able to mark the operation done
         }
       }
       _notInterrupted.set(true);
       return null;
     }

     @Override
     public String toExplainString() {
       return EXPLAIN_NAME;
     }

     @Override
     public List<Operator> getChildOperators() {
       return Collections.emptyList();
     }

     @Override
     public ExecutionStatistics getExecutionStatistics() {
       return new ExecutionStatistics(0, 0, 0, 0);
     }

     @Override
     public IndexSegment getIndexSegment() {
       if (_segmentSupplier != null) {
         return _segmentSupplier.get();
       }
       return super.getIndexSegment();
     }
   }
 }
	/**
	* 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.
	*/
	package org.apache.pinot.core.operator.combine;

	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.List;
	import java.util.concurrent.CountDownLatch;
	import java.util.concurrent.ExecutorService;
	import java.util.concurrent.Executors;
	import java.util.concurrent.Future;
	import java.util.concurrent.TimeoutException;
	import java.util.concurrent.atomic.AtomicBoolean;
	import java.util.concurrent.atomic.AtomicReference;
	import java.util.function.Supplier;
	import org.apache.pinot.common.response.ProcessingException;
	import org.apache.pinot.core.common.Block;
	import org.apache.pinot.core.common.Operator;
	import org.apache.pinot.core.operator.BaseOperator;
	import org.apache.pinot.core.operator.ExecutionStatistics;
	import org.apache.pinot.core.operator.blocks.results.BaseResultsBlock;
	import org.apache.pinot.core.query.request.context.QueryContext;
	import org.apache.pinot.core.query.request.context.utils.QueryContextConverterUtils;
	import org.apache.pinot.segment.spi.IndexSegment;
	import org.apache.pinot.segment.spi.datasource.DataSource;
	import org.apache.pinot.segment.spi.datasource.DataSourceMetadata;
	import org.apache.pinot.spi.exception.EarlyTerminationException;
	import org.apache.pinot.spi.exception.QueryCancelledException;
	import org.apache.pinot.util.TestUtils;
	import org.testng.Assert;
	import org.testng.annotations.AfterClass;
	import org.testng.annotations.BeforeClass;
	import org.testng.annotations.Test;

	import static org.mockito.ArgumentMatchers.anyString;
	import static org.mockito.Mockito.mock;
	import static org.mockito.Mockito.when;
	import static org.testng.Assert.assertEquals;
	import static org.testng.Assert.assertFalse;
	import static org.testng.Assert.assertNotNull;
	import static org.testng.Assert.assertTrue;


	/**
	* This test mimic the behavior of combining slow operators, where operation is not done by the timeout. When the
	* combine operator returns, test whether the slow operators are properly interrupted, and if all the slow operators are
	* not running in order to safely release the segment references.
	*/
	@SuppressWarnings("rawtypes")
	public class CombineSlowOperatorsTest {
	private static final int NUM_OPERATORS = 10;
	private static final int NUM_THREADS = 2;
	private static final long TIMEOUT_MS = 100L;

	private ExecutorService _executorService;

	@BeforeClass
	public void setUp() {
	_executorService = Executors.newFixedThreadPool(NUM_THREADS);
	}

	@Test
	public void testSelectionOnlyCombineOperator() {
	List<Operator> operators = getOperators();
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable");
	queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
	SelectionOnlyCombineOperator combineOperator =
	new SelectionOnlyCombineOperator(operators, queryContext, _executorService);
	testCombineOperator(operators, combineOperator);
	}

	// NOTE: Skip the test for SelectionOrderByCombineOperator because it requires SelectionOrderByOperator for the early
	// termination optimization.

	@Test
	public void testAggregationOnlyCombineOperator() {
	List<Operator> operators = getOperators();
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable");
	queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
	AggregationCombineOperator combineOperator =
	new AggregationCombineOperator(operators, queryContext, _executorService);
	testCombineOperator(operators, combineOperator);
	}

	@Test
	public void testGroupByOrderByCombineOperator() {
	List<Operator> operators = getOperators();
	QueryContext queryContext =
	QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable GROUP BY column");
	queryContext.setEndTimeMs(System.currentTimeMillis() + TIMEOUT_MS);
	GroupByCombineOperator combineOperator = new GroupByCombineOperator(operators, queryContext, _executorService);
	testCombineOperator(operators, combineOperator);
	}

	@Test
	public void testCancelSelectionOnlyCombineOperator() {
	// Just need to wait for one operator to start running.
	CountDownLatch ready = new CountDownLatch(1);
	List<Operator> operators = getOperators(ready, null);
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable");
	queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
	SelectionOnlyCombineOperator combineOperator =
	new SelectionOnlyCombineOperator(operators, queryContext, _executorService);
	testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
	}

	@Test
	public void testCancelSelectionOrderByCombineOperator() {
	CountDownLatch ready = new CountDownLatch(1);
	List<Operator> operators = getOperators(ready, null);
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable ORDER BY column");
	queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
	SelectionOrderByCombineOperator combineOperator =
	new SelectionOrderByCombineOperator(operators, queryContext, _executorService);
	testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
	}

	@Test
	public void testCancelMinMaxValueBasedSelectionOrderByCombineOperator() {
	CountDownLatch ready = new CountDownLatch(1);
	List<Operator> operators = getOperators(ready, () -> {
	IndexSegment seg = mock(IndexSegment.class);
	DataSource ds = mock(DataSource.class);
	DataSourceMetadata dsmd = mock(DataSourceMetadata.class);
	when(dsmd.getMinValue()).thenReturn(100L);
	when(dsmd.getMaxValue()).thenReturn(200L);
	when(seg.getDataSource(anyString())).thenReturn(ds);
	when(ds.getDataSourceMetadata()).thenReturn(dsmd);
	return seg;
	});
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT * FROM testTable ORDER BY column");
	queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
	SelectionOrderByCombineOperator combineOperator =
	new SelectionOrderByCombineOperator(operators, queryContext, _executorService);
	testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
	}

	@Test
	public void testCancelAggregationOnlyCombineOperator() {
	CountDownLatch ready = new CountDownLatch(1);
	List<Operator> operators = getOperators(ready, null);
	QueryContext queryContext = QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable");
	queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
	AggregationCombineOperator combineOperator =
	new AggregationCombineOperator(operators, queryContext, _executorService);
	testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
	}

	@Test
	public void testCancelGroupByOrderByCombineOperator() {
	CountDownLatch ready = new CountDownLatch(1);
	List<Operator> operators = getOperators(ready, null);
	QueryContext queryContext =
	QueryContextConverterUtils.getQueryContext("SELECT COUNT(*) FROM testTable GROUP BY column");
	queryContext.setEndTimeMs(System.currentTimeMillis() + 10000);
	GroupByCombineOperator combineOperator = new GroupByCombineOperator(operators, queryContext, _executorService);
	testCancelCombineOperator(combineOperator, ready, "Cancelled while merging results blocks");
	}

	private void testCancelCombineOperator(BaseCombineOperator combineOperator, CountDownLatch ready, String errMsg) {
	AtomicReference<Exception> exp = new AtomicReference<>();
	ExecutorService combineExecutor = Executors.newSingleThreadExecutor();
	try {
	Future<?> future = combineExecutor.submit(() -> {
	try {
	return combineOperator.nextBlock();
	} catch (Exception e) {
	exp.set(e);
	throw e;
	}
	});
	ready.await();
	// At this point, the combineOperator is or will be waiting on future.get() for all sub operators, and the
	// waiting can be cancelled as below.
	future.cancel(true);
	} catch (Exception e) {
	Assert.fail();
	} finally {
	combineExecutor.shutdownNow();
	}
	TestUtils.waitForCondition((aVoid) -> exp.get() instanceof QueryCancelledException, 10_000,
	"Should have been cancelled");
	assertEquals(exp.get().getMessage(), errMsg);
	}

	/**
	* NOTE: It is hard to test the logger behavior, but only one error message about the query timeout should be logged
	* for each query.
	*/
	private void testCombineOperator(List<Operator> operators, BaseOperator combineOperator) {
	BaseResultsBlock intermediateResultsBlock = (BaseResultsBlock) combineOperator.nextBlock();
	List<ProcessingException> processingExceptions = intermediateResultsBlock.getProcessingExceptions();
	assertNotNull(processingExceptions);
	assertEquals(processingExceptions.size(), 1);
	assertTrue(processingExceptions.get(0).getMessage().contains(TimeoutException.class.getName()));

	// When the CombineOperator returns, all operators should be either not scheduled or interrupted, and no operator
	// should be running so that the segment references can be safely released
	for (Operator operator : operators) {
	SlowOperator slowOperator = (SlowOperator) operator;
	assertFalse(slowOperator._operationInProgress.get());
	assertFalse(slowOperator._notInterrupted.get());
	}
	}

	@AfterClass
	public void tearDown() {
	_executorService.shutdown();
	}

	private List<Operator> getOperators() {
	return getOperators(null, null);
	}

	private List<Operator> getOperators(CountDownLatch ready, Supplier<IndexSegment> segmentSupplier) {
	List<Operator> operators = new ArrayList<>(NUM_OPERATORS);
	for (int i = 0; i < NUM_OPERATORS; i++) {
	operators.add(new SlowOperator(ready, segmentSupplier));
	}
	return operators;
	}

	private static class SlowOperator extends BaseOperator {
	private static final String EXPLAIN_NAME = "SLOW";

	final AtomicBoolean _operationInProgress = new AtomicBoolean();
	final AtomicBoolean _notInterrupted = new AtomicBoolean();
	private final CountDownLatch _ready;
	private final Supplier<IndexSegment> _segmentSupplier;

	public SlowOperator(CountDownLatch ready, Supplier<IndexSegment> segmentSupplier) {
	_ready = ready;
	_segmentSupplier = segmentSupplier;
	}

	@Override
	protected Block getNextBlock() {
	_operationInProgress.set(true);
	if (_ready != null) {
	_ready.countDown();
	}
	try {
	Thread.sleep(3_600_000L);
	} catch (InterruptedException e) {
	// Thread should be interrupted for early-termination
	throw new EarlyTerminationException();
	} finally {
	// Wait for 100 milliseconds before marking the operation done
	try {
	Thread.sleep(100L);
	_operationInProgress.set(false);
	} catch (InterruptedException e) {
	// Thread should not be interrupted again, and we should be able to mark the operation done
	}
	}
	_notInterrupted.set(true);
	return null;
	}

	@Override
	public String toExplainString() {
	return EXPLAIN_NAME;
	}

	@Override
	public List<Operator> getChildOperators() {
	return Collections.emptyList();
	}

	@Override
	public ExecutionStatistics getExecutionStatistics() {
	return new ExecutionStatistics(0, 0, 0, 0);
	}

	@Override
	public IndexSegment getIndexSegment() {
	if (_segmentSupplier != null) {
	return _segmentSupplier.get();
	}
	return super.getIndexSegment();
	}
	}
	}