HBASE-910 Scanner misses columns / rows when the scanner is obtained durring a memcache flush

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@718865 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Michael Stack 2008-11-19 06:48:55 +00:00
parent 6c89d36cef
commit 0d735d26a9
3 changed files with 161 additions and 40 deletions

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@ -77,6 +77,8 @@ Release 0.19.0 - Unreleased
HBASE-1003 If cell exceeds TTL but not VERSIONs, will not be removed during
major compaction
HBASE-1005 Regex and string comparison operators for ColumnValueFilter
HBASE-910 Scanner misses columns / rows when the scanner is obtained
durring a memcache flush
IMPROVEMENTS
HBASE-901 Add a limit to key length, check key and value length on client side

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@ -21,13 +21,12 @@
package org.apache.hadoop.hbase.regionserver;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
@ -36,11 +35,12 @@ import org.apache.hadoop.hbase.HStoreKey;
import org.apache.hadoop.hbase.filter.RowFilterInterface;
import org.apache.hadoop.hbase.io.Cell;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.io.MapFile;
/**
* Scanner scans both the memcache and the HStore
*/
class HStoreScanner implements InternalScanner {
class HStoreScanner implements InternalScanner, ChangedReadersObserver {
static final Log LOG = LogFactory.getLog(HStoreScanner.class);
private InternalScanner[] scanners;
@ -50,6 +50,15 @@ class HStoreScanner implements InternalScanner {
private boolean multipleMatchers = false;
private RowFilterInterface dataFilter;
private HStore store;
private final long timestamp;
private final byte [][] targetCols;
// Indices for memcache scanner and hstorefile scanner.
private static final int MEMS_INDEX = 0;
private static final int HSFS_INDEX = MEMS_INDEX + 1;
// Used around transition from no storefile to the first.
private final ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
/** Create an Scanner with a handle on the memcache and HStore files. */
@SuppressWarnings("unchecked")
@ -64,51 +73,72 @@ class HStoreScanner implements InternalScanner {
this.scanners = new InternalScanner[2];
this.resultSets = new TreeMap[scanners.length];
this.keys = new HStoreKey[scanners.length];
// Save these args in case we need them later handling change in readers
// See updateReaders below.
this.timestamp = timestamp;
this.targetCols = targetCols;
try {
scanners[0] = store.memcache.getScanner(timestamp, targetCols, firstRow);
scanners[1] = new StoreFileScanner(store, timestamp, targetCols, firstRow);
for (int i = 0; i < scanners.length; i++) {
if (scanners[i].isWildcardScanner()) {
this.wildcardMatch = true;
}
if (scanners[i].isMultipleMatchScanner()) {
this.multipleMatchers = true;
}
}
} catch(IOException e) {
for (int i = 0; i < this.scanners.length; i++) {
if(scanners[i] != null) {
closeScanner(i);
}
scanners[MEMS_INDEX] =
store.memcache.getScanner(timestamp, targetCols, firstRow);
scanners[HSFS_INDEX] =
new StoreFileScanner(store, timestamp, targetCols, firstRow);
for (int i = MEMS_INDEX; i < scanners.length; i++) {
checkScannerFlags(i);
}
} catch (IOException e) {
doClose();
throw e;
}
// Advance to the first key in each scanner.
// All results will match the required column-set and scanTime.
for (int i = 0; i < scanners.length; i++) {
keys[i] = new HStoreKey();
resultSets[i] = new TreeMap<byte [], Cell>(Bytes.BYTES_COMPARATOR);
if(scanners[i] != null && !scanners[i].next(keys[i], resultSets[i])) {
closeScanner(i);
for (int i = MEMS_INDEX; i < scanners.length; i++) {
setupScanner(i);
}
this.store.addChangedReaderObserver(this);
}
/*
* @param i Index.
*/
private void checkScannerFlags(final int i) {
if (this.scanners[i].isWildcardScanner()) {
this.wildcardMatch = true;
}
if (this.scanners[i].isMultipleMatchScanner()) {
this.multipleMatchers = true;
}
}
/*
* Do scanner setup.
* @param i
* @throws IOException
*/
private void setupScanner(final int i) throws IOException {
this.keys[i] = new HStoreKey();
this.resultSets[i] = new TreeMap<byte [], Cell>(Bytes.BYTES_COMPARATOR);
if (this.scanners[i] != null && !this.scanners[i].next(this.keys[i], this.resultSets[i])) {
closeScanner(i);
}
}
/** @return true if the scanner is a wild card scanner */
public boolean isWildcardScanner() {
return wildcardMatch;
return this.wildcardMatch;
}
/** @return true if the scanner is a multiple match scanner */
public boolean isMultipleMatchScanner() {
return multipleMatchers;
return this.multipleMatchers;
}
public boolean next(HStoreKey key, SortedMap<byte [], Cell> results)
throws IOException {
this.lock.readLock().lock();
try {
// Filtered flag is set by filters. If a cell has been 'filtered out'
// -- i.e. it is not to be returned to the caller -- the flag is 'true'.
boolean filtered = true;
@ -243,6 +273,9 @@ class HStoreScanner implements InternalScanner {
}
return moreToFollow;
} finally {
this.lock.readLock().unlock();
}
}
/** Shut down a single scanner */
@ -261,10 +294,43 @@ class HStoreScanner implements InternalScanner {
}
public void close() {
for(int i = 0; i < scanners.length; i++) {
if(scanners[i] != null) {
this.store.deleteChangedReaderObserver(this);
doClose();
}
private void doClose() {
for (int i = MEMS_INDEX; i < scanners.length; i++) {
if (scanners[i] != null) {
closeScanner(i);
}
}
}
// Implementation of ChangedReadersObserver
public void updateReaders() throws IOException {
this.lock.writeLock().lock();
try {
MapFile.Reader [] readers = this.store.getReaders();
if (this.scanners[HSFS_INDEX] == null && readers != null &&
readers.length > 0) {
// Presume that we went from no readers to at least one -- need to put
// a HStoreScanner in place.
try {
// I think its safe getting key from mem at this stage -- it shouldn't have
// been flushed yet
this.scanners[HSFS_INDEX] = new StoreFileScanner(this.store,
this.timestamp, this. targetCols, this.keys[MEMS_INDEX].getRow());
checkScannerFlags(HSFS_INDEX);
setupScanner(HSFS_INDEX);
LOG.debug("Added a StoreFileScanner to outstanding HStoreScanner");
} catch (IOException e) {
doClose();
throw e;
}
}
} finally {
this.lock.writeLock().unlock();
}
}
}

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@ -22,25 +22,30 @@ package org.apache.hadoop.hbase.regionserver;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.SortedMap;
import java.util.TreeMap;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.Writables;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.HBaseTestCase;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HServerAddress;
import org.apache.hadoop.hbase.HStoreKey;
import org.apache.hadoop.hbase.io.BatchUpdate;
import org.apache.hadoop.hbase.io.Cell;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.Writables;
import org.apache.hadoop.hdfs.MiniDFSCluster;
/**
* Test of a long-lived scanner validating as we go.
*/
public class TestScanner extends HBaseTestCase {
private static final byte [] FIRST_ROW = HConstants.EMPTY_START_ROW;
private final Log LOG = LogFactory.getLog(this.getClass());
private static final byte [] FIRST_ROW =
HConstants.EMPTY_START_ROW;
private static final byte [][] COLS = {
HConstants.COLUMN_FAMILY
};
@ -52,7 +57,8 @@ public class TestScanner extends HBaseTestCase {
private static final byte [] ROW_KEY =
HRegionInfo.ROOT_REGIONINFO.getRegionName();
private static final HRegionInfo REGION_INFO = HRegionInfo.ROOT_REGIONINFO;
private static final HRegionInfo REGION_INFO =
HRegionInfo.ROOT_REGIONINFO;
private static final long START_CODE = Long.MAX_VALUE;
@ -85,7 +91,6 @@ public class TestScanner extends HBaseTestCase {
/** Use a scanner to get the region info and then validate the results */
private void scan(boolean validateStartcode, String serverName)
throws IOException {
InternalScanner scanner = null;
TreeMap<byte [], Cell> results =
new TreeMap<byte [], Cell>(Bytes.BYTES_COMPARATOR);
@ -141,6 +146,54 @@ public class TestScanner extends HBaseTestCase {
validateRegionInfo(bytes);
}
/**
* HBase-910.
* @throws Exception
*/
public void testScanAndConcurrentFlush() throws Exception {
this.r = createNewHRegion(REGION_INFO.getTableDesc(), null, null);
HRegionIncommon hri = new HRegionIncommon(r);
try {
addContent(hri, Bytes.toString(HConstants.COL_REGIONINFO));
int count = count(hri, -1);
assertEquals(count, count(hri, 100));
assertEquals(count, count(hri, 0));
assertEquals(count, count(hri, count - 1));
} finally {
this.r.close();
this.r.getLog().closeAndDelete();
shutdownDfs(cluster);
}
}
/*
* @param hri Region
* @param flushIndex At what row we start the flush.
* @return Count of rows found.
* @throws IOException
*/
private int count(final HRegionIncommon hri, final int flushIndex)
throws IOException {
LOG.info("Taking out counting scan");
ScannerIncommon s = hri.getScanner(EXPLICIT_COLS,
HConstants.EMPTY_START_ROW, HConstants.LATEST_TIMESTAMP);
HStoreKey key = new HStoreKey();
SortedMap<byte [], Cell> values =
new TreeMap<byte [], Cell>(Bytes.BYTES_COMPARATOR);
int count = 0;
while (s.next(key, values)) {
count++;
if (flushIndex == count) {
LOG.info("Starting flush at flush index " + flushIndex);
hri.flushcache();
LOG.info("Finishing flush");
}
}
s.close();
LOG.info("Found " + count + " items");
return count;
}
/** The test!
* @throws IOException
*/