HBASE-5515 Add a processRow API that supports atomic multiple reads and writes on a row (Scott Chen)
git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1298533 13f79535-47bb-0310-9956-ffa450edef68
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@ -0,0 +1,85 @@
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/*
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* Licensed to the Apache Software Foundation (ASF) under one
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* or more contributor license agreements. See the NOTICE file
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* distributed with this work for additional information
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* regarding copyright ownership. The ASF licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.hadoop.hbase.coprocessor;
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import java.io.IOException;
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import java.util.List;
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import java.util.UUID;
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import org.apache.hadoop.classification.InterfaceAudience;
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import org.apache.hadoop.hbase.KeyValue;
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import org.apache.hadoop.hbase.client.Scan;
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import org.apache.hadoop.hbase.regionserver.wal.WALEdit;
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import org.apache.hadoop.io.Writable;
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/**
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* Defines the procedure to atomically perform multiple scans and mutations
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* on one single row. The generic type parameter T is the return type of
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* RowProcessor.getResult().
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*/
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@InterfaceAudience.Public
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public interface RowProcessor<T> extends Writable {
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/**
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* Which row to perform the read-write
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*/
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byte[] getRow();
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/**
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* Obtain the processing result
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*/
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T getResult();
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/**
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* Is this operation read only? If this is true, process() should not add
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* any mutations or it throws IOException.
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* @return ture if read only operation
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*/
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boolean readOnly();
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/**
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* HRegion calls this to process a row. You should override this to create
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* your own RowProcessor.
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*
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* @param now the current system millisecond
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* @param scanner the call back object the can be used to scan the row
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* @param mutations the mutations for HRegion to do
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* @param walEdit the wal edit here allows inject some other meta data
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*/
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void process(long now,
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RowProcessor.RowScanner scanner,
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List<KeyValue> mutations,
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WALEdit walEdit) throws IOException;
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/**
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* The call back provided by HRegion to perform the scans on the row
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*/
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public interface RowScanner {
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/**
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* @param scan The object defines what to read
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* @param result The scan results will be added here
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*/
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void doScan(Scan scan, List<KeyValue> result) throws IOException;
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}
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/**
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* @return The replication cluster id.
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*/
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UUID getClusterId();
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}
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@ -49,9 +49,11 @@ import java.util.concurrent.CountDownLatch;
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import java.util.concurrent.ExecutionException;
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import java.util.concurrent.ExecutorCompletionService;
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import java.util.concurrent.Future;
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import java.util.concurrent.FutureTask;
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import java.util.concurrent.ThreadFactory;
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import java.util.concurrent.ThreadPoolExecutor;
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import java.util.concurrent.TimeUnit;
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import java.util.concurrent.TimeoutException;
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import java.util.concurrent.atomic.AtomicBoolean;
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import java.util.concurrent.atomic.AtomicInteger;
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import java.util.concurrent.atomic.AtomicLong;
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@ -78,7 +80,6 @@ import org.apache.hadoop.hbase.KeyValue;
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import org.apache.hadoop.hbase.NotServingRegionException;
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import org.apache.hadoop.hbase.UnknownScannerException;
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import org.apache.hadoop.hbase.client.Append;
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import org.apache.hadoop.hbase.client.RowMutations;
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import org.apache.hadoop.hbase.client.Delete;
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import org.apache.hadoop.hbase.client.Get;
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import org.apache.hadoop.hbase.client.Increment;
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@ -88,13 +89,14 @@ import org.apache.hadoop.hbase.client.Put;
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import org.apache.hadoop.hbase.client.Result;
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import org.apache.hadoop.hbase.client.Row;
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import org.apache.hadoop.hbase.client.RowLock;
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import org.apache.hadoop.hbase.client.RowMutations;
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import org.apache.hadoop.hbase.client.Scan;
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import org.apache.hadoop.hbase.client.coprocessor.Exec;
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import org.apache.hadoop.hbase.client.coprocessor.ExecResult;
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import org.apache.hadoop.hbase.coprocessor.RowProcessor;
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import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
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import org.apache.hadoop.hbase.filter.Filter;
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import org.apache.hadoop.hbase.filter.IncompatibleFilterException;
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import org.apache.hadoop.hbase.filter.NullComparator;
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import org.apache.hadoop.hbase.filter.WritableByteArrayComparable;
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import org.apache.hadoop.hbase.io.HeapSize;
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import org.apache.hadoop.hbase.io.TimeRange;
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@ -228,13 +230,14 @@ public class HRegion implements HeapSize { // , Writable{
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final Configuration conf;
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final int rowLockWaitDuration;
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static final int DEFAULT_ROWLOCK_WAIT_DURATION = 30000;
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static final long DEFAULT_ROW_PROCESSOR_TIMEOUT = 10 * 1000L;
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final HRegionInfo regionInfo;
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final Path regiondir;
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KeyValue.KVComparator comparator;
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private ConcurrentHashMap<RegionScanner, Long> scannerReadPoints;
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/*
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/**
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* @return The smallest mvcc readPoint across all the scanners in this
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* region. Writes older than this readPoint, are included in every
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* read operation.
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@ -297,6 +300,7 @@ public class HRegion implements HeapSize { // , Writable{
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long memstoreFlushSize;
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final long timestampSlop;
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final long rowProcessorTimeout;
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private volatile long lastFlushTime;
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final RegionServerServices rsServices;
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private List<Pair<Long, Long>> recentFlushes = new ArrayList<Pair<Long,Long>>();
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@ -413,6 +417,7 @@ public class HRegion implements HeapSize { // , Writable{
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this.rsServices = null;
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this.fs = null;
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this.timestampSlop = HConstants.LATEST_TIMESTAMP;
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this.rowProcessorTimeout = DEFAULT_ROW_PROCESSOR_TIMEOUT;
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this.memstoreFlushSize = 0L;
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this.log = null;
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this.regiondir = null;
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@ -476,6 +481,9 @@ public class HRegion implements HeapSize { // , Writable{
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"hbase.hregion.keyvalue.timestamp.slop.millisecs",
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HConstants.LATEST_TIMESTAMP);
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this.rowProcessorTimeout = conf.getLong(
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"hbase.hregion.row.processor.timeout", DEFAULT_ROW_PROCESSOR_TIMEOUT);
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// don't initialize coprocessors if not running within a regionserver
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// TODO: revisit if coprocessors should load in other cases
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if (rsServices != null) {
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@ -4288,6 +4296,155 @@ public class HRegion implements HeapSize { // , Writable{
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}
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}
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/**
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* Performs atomic multiple reads and writes on a given row.
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* @param processor The object defines the reads and writes to a row.
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*/
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public void processRow(RowProcessor<?> processor)
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throws IOException {
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byte[] row = processor.getRow();
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checkRow(row, "processRow");
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if (!processor.readOnly()) {
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checkReadOnly();
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}
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checkResources();
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MultiVersionConsistencyControl.WriteEntry writeEntry = null;
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startRegionOperation();
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boolean locked = false;
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boolean walSyncSuccessful = false;
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Integer rowLockID = null;
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long addedSize = 0;
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List<KeyValue> mutations = new ArrayList<KeyValue>();
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try {
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// 1. Row lock
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rowLockID = getLock(null, row, true);
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// 2. Region lock
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this.updatesLock.readLock().lock();
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locked = true;
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long now = EnvironmentEdgeManager.currentTimeMillis();
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try {
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// 3. Let the processor scan the row and generate mutations
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WALEdit walEdits = new WALEdit();
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doProcessRowWithTimeout(processor, now, rowScanner, mutations,
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walEdits, rowProcessorTimeout);
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if (processor.readOnly() && !mutations.isEmpty()) {
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throw new IOException(
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"Processor is readOnly but generating mutations on row:" +
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Bytes.toStringBinary(row));
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}
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if (!mutations.isEmpty()) {
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// 4. Get a mvcc write number
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writeEntry = mvcc.beginMemstoreInsert();
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// 5. Apply to memstore and a WALEdit
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for (KeyValue kv : mutations) {
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kv.setMemstoreTS(writeEntry.getWriteNumber());
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walEdits.add(kv);
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addedSize += stores.get(kv.getFamily()).add(kv);
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}
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long txid = 0;
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// 6. Append no sync
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if (!walEdits.isEmpty()) {
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txid = this.log.appendNoSync(this.regionInfo,
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this.htableDescriptor.getName(), walEdits,
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processor.getClusterId(), now, this.htableDescriptor);
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}
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// 7. Release region lock
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if (locked) {
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this.updatesLock.readLock().unlock();
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locked = false;
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}
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// 8. Release row lock
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if (rowLockID != null) {
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releaseRowLock(rowLockID);
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rowLockID = null;
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}
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// 9. Sync edit log
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if (txid != 0) {
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this.log.sync(txid);
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}
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walSyncSuccessful = true;
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}
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} finally {
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if (!mutations.isEmpty() && !walSyncSuccessful) {
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LOG.warn("Wal sync failed. Roll back " + mutations.size() +
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" memstore keyvalues for row:" + processor.getRow());
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for (KeyValue kv : mutations) {
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stores.get(kv.getFamily()).rollback(kv);
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}
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}
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// 10. Roll mvcc forward
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if (writeEntry != null) {
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mvcc.completeMemstoreInsert(writeEntry);
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writeEntry = null;
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}
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if (locked) {
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this.updatesLock.readLock().unlock();
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locked = false;
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}
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if (rowLockID != null) {
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releaseRowLock(rowLockID);
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rowLockID = null;
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}
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}
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} finally {
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closeRegionOperation();
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if (!mutations.isEmpty() &&
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isFlushSize(this.addAndGetGlobalMemstoreSize(addedSize))) {
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requestFlush();
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}
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}
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}
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private void doProcessRowWithTimeout(final RowProcessor<?> processor,
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final long now,
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final RowProcessor.RowScanner scanner,
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final List<KeyValue> mutations,
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final WALEdit walEdits,
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final long timeout) throws IOException {
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FutureTask<Void> task =
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new FutureTask<Void>(new Callable<Void>() {
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@Override
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public Void call() throws IOException {
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processor.process(now, scanner, mutations, walEdits);
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return null;
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}
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});
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Thread t = new Thread(task);
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t.setDaemon(true);
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t.start();
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try {
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task.get(timeout, TimeUnit.MILLISECONDS);
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} catch (TimeoutException te) {
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LOG.error("RowProcessor timeout on row:" +
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Bytes.toStringBinary(processor.getRow()) + " timeout:" + timeout, te);
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throw new IOException(te);
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} catch (Exception e) {
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throw new IOException(e);
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}
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}
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final private RowProcessor.RowScanner rowScanner =
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new RowProcessor.RowScanner() {
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@Override
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public void doScan(Scan scan, List<KeyValue> result) throws IOException {
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InternalScanner scanner = null;
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try {
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scan.setIsolationLevel(IsolationLevel.READ_UNCOMMITTED);
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scanner = HRegion.this.getScanner(scan);
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result.clear();
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scanner.next(result);
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} finally {
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if (scanner != null) scanner.close();
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}
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}
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};
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// TODO: There's a lot of boiler plate code identical
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// to increment... See how to better unify that.
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/**
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@ -4660,8 +4817,8 @@ public class HRegion implements HeapSize { // , Writable{
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public static final long FIXED_OVERHEAD = ClassSize.align(
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ClassSize.OBJECT +
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ClassSize.ARRAY +
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30 * ClassSize.REFERENCE + Bytes.SIZEOF_INT +
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(5 * Bytes.SIZEOF_LONG) +
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31 * ClassSize.REFERENCE + Bytes.SIZEOF_INT +
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(6 * Bytes.SIZEOF_LONG) +
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Bytes.SIZEOF_BOOLEAN);
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public static final long DEEP_OVERHEAD = FIXED_OVERHEAD +
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@ -0,0 +1,321 @@
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/**
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* Licensed to the Apache Software Foundation (ASF) under one
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* or more contributor license agreements. See the NOTICE file
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* distributed with this work for additional information
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* regarding copyright ownership. The ASF licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.hadoop.hbase.coprocessor;
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import static org.junit.Assert.assertEquals;
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import java.io.DataInput;
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import java.io.DataOutput;
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import java.io.IOException;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.Collection;
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import java.util.HashSet;
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import java.util.List;
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import java.util.Set;
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import java.util.UUID;
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import java.util.concurrent.CountDownLatch;
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import org.apache.hadoop.conf.Configuration;
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import org.apache.hadoop.hbase.HBaseTestingUtility;
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import org.apache.hadoop.hbase.HConstants;
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import org.apache.hadoop.hbase.KeyValue;
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import org.apache.hadoop.hbase.SmallTests;
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import org.apache.hadoop.hbase.client.Get;
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import org.apache.hadoop.hbase.client.HTable;
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import org.apache.hadoop.hbase.client.Put;
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import org.apache.hadoop.hbase.client.Result;
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import org.apache.hadoop.hbase.client.Scan;
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import org.apache.hadoop.hbase.ipc.CoprocessorProtocol;
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import org.apache.hadoop.hbase.regionserver.HRegion;
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import org.apache.hadoop.hbase.regionserver.wal.HLog;
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import org.apache.hadoop.hbase.regionserver.wal.WALEdit;
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import org.apache.hadoop.hbase.util.Bytes;
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import org.junit.AfterClass;
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import org.junit.BeforeClass;
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import org.junit.Test;
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import org.junit.experimental.categories.Category;
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import com.sun.org.apache.commons.logging.Log;
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import com.sun.org.apache.commons.logging.LogFactory;
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/**
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* Verifies ProcessRowEndpoint works.
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* The tested RowProcessor performs two scans and a read-modify-write.
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*/
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@Category(SmallTests.class)
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public class TestProcessRowEndpoint {
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static final Log LOG = LogFactory.getLog(TestProcessRowEndpoint.class);
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private static final byte[] TABLE = Bytes.toBytes("testtable");
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private static final byte[] TABLE2 = Bytes.toBytes("testtable2");
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private final static byte[] ROW = Bytes.toBytes("testrow");
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private final static byte[] FAM = Bytes.toBytes("friendlist");
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// Column names
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private final static byte[] A = Bytes.toBytes("a");
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private final static byte[] B = Bytes.toBytes("b");
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private final static byte[] C = Bytes.toBytes("c");
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private final static byte[] D = Bytes.toBytes("d");
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private final static byte[] E = Bytes.toBytes("e");
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private final static byte[] F = Bytes.toBytes("f");
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private final static byte[] G = Bytes.toBytes("g");
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private final static byte[] REQUESTS = Bytes.toBytes("requests");
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private static HBaseTestingUtility util = new HBaseTestingUtility();
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private volatile int numRequests;
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private CountDownLatch startSignal;
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private CountDownLatch doneSignal;
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@BeforeClass
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public static void setupBeforeClass() throws Exception {
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Configuration conf = util.getConfiguration();
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conf.set(CoprocessorHost.REGION_COPROCESSOR_CONF_KEY,
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FriendsOfFriendsEndpoint.class.getName());
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util.startMiniCluster();
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}
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@AfterClass
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public static void tearDownAfterClass() throws Exception {
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util.shutdownMiniCluster();
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}
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@Test
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public void testSingle() throws Throwable {
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HTable table = prepareTestData(TABLE, util);
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verifyProcessRow(table);
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assertEquals(1, numRequests);
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}
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private void verifyProcessRow(HTable table) throws Throwable {
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FriendsOfFriendsProtocol processor =
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table.coprocessorProxy(FriendsOfFriendsProtocol.class, ROW);
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||||
Result result = processor.query(ROW, A);
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||||
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Set<String> friendsOfFriends = new HashSet<String>();
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for (KeyValue kv : result.raw()) {
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if (Bytes.equals(kv.getQualifier(), REQUESTS)) {
|
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numRequests = Bytes.toInt(kv.getValue());
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continue;
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||||
}
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for (byte val : kv.getValue()) {
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friendsOfFriends.add((char)val + "");
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||||
}
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||||
}
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Set<String> expected =
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new HashSet<String>(Arrays.asList(new String[]{"d", "e", "f", "g"}));
|
||||
assertEquals(expected, friendsOfFriends);
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||||
}
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||||
@Test
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public void testThreads() throws Exception {
|
||||
HTable table = prepareTestData(TABLE2, util);
|
||||
int numThreads = 1000;
|
||||
startSignal = new CountDownLatch(numThreads);
|
||||
doneSignal = new CountDownLatch(numThreads);
|
||||
for (int i = 0; i < numThreads; ++i) {
|
||||
new Thread(new QueryRunner(table)).start();
|
||||
startSignal.countDown();
|
||||
}
|
||||
doneSignal.await();
|
||||
Get get = new Get(ROW);
|
||||
LOG.debug("row keyvalues:" + stringifyKvs(table.get(get).list()));
|
||||
assertEquals(numThreads, numRequests);
|
||||
}
|
||||
|
||||
class QueryRunner implements Runnable {
|
||||
final HTable table;
|
||||
QueryRunner(final HTable table) {
|
||||
this.table = table;
|
||||
}
|
||||
@Override
|
||||
public void run() {
|
||||
try {
|
||||
startSignal.await();
|
||||
verifyProcessRow(table);
|
||||
} catch (Throwable e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
doneSignal.countDown();
|
||||
}
|
||||
}
|
||||
|
||||
static HTable prepareTestData(byte[] tableName, HBaseTestingUtility util)
|
||||
throws Exception {
|
||||
HTable table = util.createTable(tableName, FAM);
|
||||
Put put = new Put(ROW);
|
||||
put.add(FAM, A, Bytes.add(B, C)); // B, C are friends of A
|
||||
put.add(FAM, B, Bytes.add(D, E, F)); // D, E, F are friends of B
|
||||
put.add(FAM, C, G); // G is a friend of C
|
||||
table.put(put);
|
||||
return table;
|
||||
}
|
||||
|
||||
/**
|
||||
* Coprocessor protocol that finds friends of friends of a person and
|
||||
* update the number of requests.
|
||||
*/
|
||||
public static interface FriendsOfFriendsProtocol extends CoprocessorProtocol {
|
||||
|
||||
/**
|
||||
* Query a person's friends of friends
|
||||
*/
|
||||
Result query(byte[] row, byte[] person) throws IOException;
|
||||
}
|
||||
|
||||
/**
|
||||
* Finds friends of friends of a person and update the number of requests.
|
||||
*/
|
||||
public static class FriendsOfFriendsEndpoint extends BaseEndpointCoprocessor
|
||||
implements FriendsOfFriendsProtocol, RowProcessor<Result> {
|
||||
byte[] row = null;
|
||||
byte[] person = null;
|
||||
Result result = null;
|
||||
|
||||
//
|
||||
// FriendsOfFriendsProtocol method
|
||||
//
|
||||
|
||||
@Override
|
||||
public Result query(byte[] row, byte[] person) throws IOException {
|
||||
this.row = row;
|
||||
this.person = person;
|
||||
HRegion region =
|
||||
((RegionCoprocessorEnvironment) getEnvironment()).getRegion();
|
||||
region.processRow(this);
|
||||
return this.getResult();
|
||||
}
|
||||
|
||||
//
|
||||
// RowProcessor methods
|
||||
//
|
||||
|
||||
FriendsOfFriendsEndpoint() {
|
||||
}
|
||||
|
||||
@Override
|
||||
public byte[] getRow() {
|
||||
return row;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Result getResult() {
|
||||
return result;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean readOnly() {
|
||||
return false;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void process(long now, RowProcessor.RowScanner scanner,
|
||||
List<KeyValue> mutations, WALEdit walEdit) throws IOException {
|
||||
List<KeyValue> kvs = new ArrayList<KeyValue>();
|
||||
{ // First scan to get friends of the person and numRequests
|
||||
Scan scan = new Scan(row, row);
|
||||
scan.addColumn(FAM, person);
|
||||
scan.addColumn(FAM, REQUESTS);
|
||||
scanner.doScan(scan, kvs);
|
||||
}
|
||||
LOG.debug("first scan:" + stringifyKvs(kvs));
|
||||
int numRequests = 0;
|
||||
// Second scan to get friends of friends
|
||||
Scan scan = new Scan(row, row);
|
||||
for (KeyValue kv : kvs) {
|
||||
if (Bytes.equals(kv.getQualifier(), REQUESTS)) {
|
||||
numRequests = Bytes.toInt(kv.getValue());
|
||||
continue;
|
||||
}
|
||||
byte[] friends = kv.getValue();
|
||||
for (byte f : friends) {
|
||||
scan.addColumn(FAM, new byte[]{f});
|
||||
}
|
||||
}
|
||||
scanner.doScan(scan, kvs);
|
||||
|
||||
LOG.debug("second scan:" + stringifyKvs(kvs));
|
||||
numRequests += 1;
|
||||
// Construct mutations and Result
|
||||
KeyValue kv = new KeyValue(
|
||||
row, FAM, REQUESTS, now, Bytes.toBytes(numRequests));
|
||||
mutations.clear();
|
||||
mutations.add(kv);
|
||||
kvs.add(kv);
|
||||
LOG.debug("final result:" + stringifyKvs(kvs) +
|
||||
" mutations:" + stringifyKvs(mutations));
|
||||
result = new Result(kvs);
|
||||
// Inject some meta data to the walEdit
|
||||
KeyValue metaKv = new KeyValue(
|
||||
getRow(), HLog.METAFAMILY,
|
||||
Bytes.toBytes("FriendsOfFriends query"),
|
||||
person);
|
||||
walEdit.add(metaKv);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void readFields(DataInput in) throws IOException {
|
||||
this.person = Bytes.readByteArray(in);
|
||||
this.row = Bytes.readByteArray(in);
|
||||
this.result = new Result();
|
||||
result.readFields(in);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void write(DataOutput out) throws IOException {
|
||||
Bytes.writeByteArray(out, person);
|
||||
Bytes.writeByteArray(out, row);
|
||||
if (result == null) {
|
||||
new Result().write(out);
|
||||
} else {
|
||||
result.write(out);
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public UUID getClusterId() {
|
||||
return HConstants.DEFAULT_CLUSTER_ID;
|
||||
}
|
||||
}
|
||||
|
||||
static String stringifyKvs(Collection<KeyValue> kvs) {
|
||||
StringBuilder out = new StringBuilder();
|
||||
out.append("[");
|
||||
for (KeyValue kv : kvs) {
|
||||
byte[] col = kv.getQualifier();
|
||||
byte[] val = kv.getValue();
|
||||
if (Bytes.equals(col, REQUESTS)) {
|
||||
out.append(Bytes.toStringBinary(col) + ":" +
|
||||
Bytes.toInt(val) + " ");
|
||||
} else {
|
||||
out.append(Bytes.toStringBinary(col) + ":" +
|
||||
Bytes.toStringBinary(val) + " ");
|
||||
}
|
||||
}
|
||||
out.append("]");
|
||||
return out.toString();
|
||||
}
|
||||
|
||||
@org.junit.Rule
|
||||
public org.apache.hadoop.hbase.ResourceCheckerJUnitRule cu =
|
||||
new org.apache.hadoop.hbase.ResourceCheckerJUnitRule();
|
||||
}
|
Loading…
Reference in New Issue