/**
* Copyright 2010 The Apache Software Foundation
*
* 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.hadoop.hbase.regionserver;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.NavigableSet;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.KeyValue.KeyComparator;
import org.apache.hadoop.hbase.RemoteExceptionHandler;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.io.HeapSize;
import org.apache.hadoop.hbase.io.hfile.Compression;
import org.apache.hadoop.hbase.io.hfile.HFile;
import org.apache.hadoop.hbase.io.hfile.HFile.Reader;
import org.apache.hadoop.hbase.io.hfile.HFileScanner;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.ClassSize;
import org.apache.hadoop.util.StringUtils;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
/**
* A Store holds a column family in a Region. Its a memstore and a set of zero
* or more StoreFiles, which stretch backwards over time.
*
* <p>There's no reason to consider append-logging at this level; all logging
* and locking is handled at the HRegion level. Store just provides
* services to manage sets of StoreFiles. One of the most important of those
* services is compaction services where files are aggregated once they pass
* a configurable threshold.
*
* <p>Locking and transactions are handled at a higher level. This API should
* not be called directly but by an HRegion manager.
*/
public class Store implements HeapSize {
static final Log LOG = LogFactory.getLog(Store.class);
protected final MemStore memstore;
// This stores directory in the filesystem.
private final Path homedir;
private final HRegion region;
private final HColumnDescriptor family;
final FileSystem fs;
final Configuration conf;
// ttl in milliseconds.
protected long ttl;
private long majorCompactionTime;
private int maxFilesToCompact;
private final long desiredMaxFileSize;
private volatile long storeSize = 0L;
private final Object flushLock = new Object();
final ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
private final String storeNameStr;
private final boolean inMemory;
/*
* List of store files inside this store. This is an immutable list that
* is atomically replaced when its contents change.
*/
private ImmutableList<StoreFile> storefiles = null;
// All access must be synchronized.
private final CopyOnWriteArraySet<ChangedReadersObserver> changedReaderObservers =
new CopyOnWriteArraySet<ChangedReadersObserver>();
private final Object compactLock = new Object();
private final int compactionThreshold;
private final int blocksize;
private final boolean blockcache;
private final Compression.Algorithm compression;
// Comparing KeyValues
final KeyValue.KVComparator comparator;
/**
* Constructor
* @param basedir qualified path under which the region directory lives;
* generally the table subdirectory
* @param region
* @param family HColumnDescriptor for this column
* @param fs file system object
* @param conf configuration object
* failed. Can be null.
* @throws IOException
*/
protected Store(Path basedir, HRegion region, HColumnDescriptor family,
FileSystem fs, Configuration conf)
throws IOException {
HRegionInfo info = region.regionInfo;
this.fs = fs;
this.homedir = getStoreHomedir(basedir, info.getEncodedName(), family.getName());
if (!this.fs.exists(this.homedir)) {
if (!this.fs.mkdirs(this.homedir))
throw new IOException("Failed create of: " + this.homedir.toString());
}
this.region = region;
this.family = family;
this.conf = conf;
this.blockcache = family.isBlockCacheEnabled();
this.blocksize = family.getBlocksize();
this.compression = family.getCompression();
this.comparator = info.getComparator();
// getTimeToLive returns ttl in seconds. Convert to milliseconds.
this.ttl = family.getTimeToLive();
if (ttl == HConstants.FOREVER) {
// default is unlimited ttl.
ttl = Long.MAX_VALUE;
} else if (ttl == -1) {
ttl = Long.MAX_VALUE;
} else {
// second -> ms adjust for user data
this.ttl *= 1000;
}
this.memstore = new MemStore(this.comparator);
this.storeNameStr = Bytes.toString(this.family.getName());
// By default, we compact if an HStore has more than
// MIN_COMMITS_FOR_COMPACTION map files
this.compactionThreshold =
conf.getInt("hbase.hstore.compactionThreshold", 3);
// Check if this is in-memory store
this.inMemory = family.isInMemory();
// By default we split region if a file > HConstants.DEFAULT_MAX_FILE_SIZE.
long maxFileSize = info.getTableDesc().getMaxFileSize();
if (maxFileSize == HConstants.DEFAULT_MAX_FILE_SIZE) {
maxFileSize = conf.getLong("hbase.hregion.max.filesize",
HConstants.DEFAULT_MAX_FILE_SIZE);
}
this.desiredMaxFileSize = maxFileSize;
this.majorCompactionTime =
conf.getLong(HConstants.MAJOR_COMPACTION_PERIOD, 86400000);
if (family.getValue(HConstants.MAJOR_COMPACTION_PERIOD) != null) {
String strCompactionTime =
family.getValue(HConstants.MAJOR_COMPACTION_PERIOD);
this.majorCompactionTime = (new Long(strCompactionTime)).longValue();
}
this.maxFilesToCompact = conf.getInt("hbase.hstore.compaction.max", 10);
this.storefiles = ImmutableList.copyOf(loadStoreFiles());
}
HColumnDescriptor getFamily() {
return this.family;
}
/**
* @return The maximum sequence id in all store files.
*/
long getMaxSequenceId() {
return StoreFile.getMaxSequenceIdInList(this.getStorefiles());
}
/**
* @param tabledir
* @param encodedName Encoded region name.
* @param family
* @return Path to family/Store home directory.
*/
public static Path getStoreHomedir(final Path tabledir,
final String encodedName, final byte [] family) {
return new Path(tabledir, new Path(encodedName,
new Path(Bytes.toString(family))));
}
/**
* Return the directory in which this store stores its
* StoreFiles
*/
public Path getHomedir() {
return homedir;
}
/*
* Creates a series of StoreFile loaded from the given directory.
* @throws IOException
*/
private List<StoreFile> loadStoreFiles()
throws IOException {
ArrayList<StoreFile> results = new ArrayList<StoreFile>();
FileStatus files[] = this.fs.listStatus(this.homedir);
for (int i = 0; files != null && i < files.length; i++) {
// Skip directories.
if (files[i].isDir()) {
continue;
}
Path p = files[i].getPath();
// Check for empty file. Should never be the case but can happen
// after data loss in hdfs for whatever reason (upgrade, etc.): HBASE-646
if (this.fs.getFileStatus(p).getLen() <= 0) {
LOG.warn("Skipping " + p + " because its empty. HBASE-646 DATA LOSS?");
continue;
}
StoreFile curfile = null;
try {
curfile = new StoreFile(fs, p, blockcache, this.conf,
this.family.getBloomFilterType(), this.inMemory);
curfile.createReader();
} catch (IOException ioe) {
LOG.warn("Failed open of " + p + "; presumption is that file was " +
"corrupted at flush and lost edits picked up by commit log replay. " +
"Verify!", ioe);
continue;
}
long length = curfile.getReader().length();
this.storeSize += length;
if (LOG.isDebugEnabled()) {
LOG.debug("loaded " + curfile.toStringDetailed());
}
results.add(curfile);
}
Collections.sort(results, StoreFile.Comparators.FLUSH_TIME);
return results;
}
/**
* Adds a value to the memstore
*
* @param kv
* @return memstore size delta
*/
protected long add(final KeyValue kv) {
lock.readLock().lock();
try {
return this.memstore.add(kv);
} finally {
lock.readLock().unlock();
}
}
/**
* Adds a value to the memstore
*
* @param kv
* @return memstore size delta
*/
protected long delete(final KeyValue kv) {
lock.readLock().lock();
try {
return this.memstore.delete(kv);
} finally {
lock.readLock().unlock();
}
}
/**
* @return All store files.
*/
List<StoreFile> getStorefiles() {
return this.storefiles;
}
public void bulkLoadHFile(String srcPathStr) throws IOException {
Path srcPath = new Path(srcPathStr);
HFile.Reader reader = null;
try {
LOG.info("Validating hfile at " + srcPath + " for inclusion in "
+ "store " + this + " region " + this.region);
reader = new HFile.Reader(srcPath.getFileSystem(conf),
srcPath, null, false);
reader.loadFileInfo();
byte[] firstKey = reader.getFirstRowKey();
byte[] lastKey = reader.getLastRowKey();
LOG.debug("HFile bounds: first=" + Bytes.toStringBinary(firstKey) +
" last=" + Bytes.toStringBinary(lastKey));
LOG.debug("Region bounds: first=" +
Bytes.toStringBinary(region.getStartKey()) +
" last=" + Bytes.toStringBinary(region.getEndKey()));
HRegionInfo hri = region.getRegionInfo();
if (!hri.containsRange(firstKey, lastKey)) {
throw new WrongRegionException(
"Bulk load file " + srcPathStr + " does not fit inside region "
+ this.region);
}
} finally {
if (reader != null) reader.close();
}
// Move the file if it's on another filesystem
FileSystem srcFs = srcPath.getFileSystem(conf);
if (!srcFs.equals(fs)) {
LOG.info("File " + srcPath + " on different filesystem than " +
"destination store - moving to this filesystem.");
Path tmpPath = getTmpPath();
FileUtil.copy(srcFs, srcPath, fs, tmpPath, false, conf);
LOG.info("Copied to temporary path on dst filesystem: " + tmpPath);
srcPath = tmpPath;
}
Path dstPath = StoreFile.getRandomFilename(fs, homedir);
LOG.info("Renaming bulk load file " + srcPath + " to " + dstPath);
StoreFile.rename(fs, srcPath, dstPath);
StoreFile sf = new StoreFile(fs, dstPath, blockcache,
this.conf, this.family.getBloomFilterType(), this.inMemory);
sf.createReader();
LOG.info("Moved hfile " + srcPath + " into store directory " +
homedir + " - updating store file list.");
// Append the new storefile into the list
this.lock.writeLock().lock();
try {
ArrayList<StoreFile> newFiles = new ArrayList<StoreFile>(storefiles);
newFiles.add(sf);
this.storefiles = ImmutableList.copyOf(newFiles);
notifyChangedReadersObservers();
} finally {
this.lock.writeLock().unlock();
}
LOG.info("Successfully loaded store file " + srcPath
+ " into store " + this + " (new location: " + dstPath + ")");
}
/**
* Get a temporary path in this region. These temporary files
* will get cleaned up when the region is re-opened if they are
* still around.
*/
private Path getTmpPath() throws IOException {
return StoreFile.getRandomFilename(
fs, region.getTmpDir());
}
/**
* Close all the readers
*
* We don't need to worry about subsequent requests because the HRegion holds
* a write lock that will prevent any more reads or writes.
*
* @throws IOException
*/
ImmutableList<StoreFile> close() throws IOException {
this.lock.writeLock().lock();
try {
ImmutableList<StoreFile> result = storefiles;
// Clear so metrics doesn't find them.
storefiles = ImmutableList.of();
for (StoreFile f: result) {
f.closeReader();
}
LOG.debug("closed " + this.storeNameStr);
return result;
} finally {
this.lock.writeLock().unlock();
}
}
/**
* Snapshot this stores memstore. Call before running
* {@link #flushCache(long, SortedSet<KeyValue>)} so it has some work to do.
*/
void snapshot() {
this.memstore.snapshot();
}
/**
* Write out current snapshot. Presumes {@link #snapshot()} has been called
* previously.
* @param logCacheFlushId flush sequence number
* @return true if a compaction is needed
* @throws IOException
*/
private StoreFile flushCache(final long logCacheFlushId,
SortedSet<KeyValue> snapshot) throws IOException {
// If an exception happens flushing, we let it out without clearing
// the memstore snapshot. The old snapshot will be returned when we say
// 'snapshot', the next time flush comes around.
return internalFlushCache(snapshot, logCacheFlushId);
}
/*
* @param cache
* @param logCacheFlushId
* @return StoreFile created.
* @throws IOException
*/
private StoreFile internalFlushCache(final SortedSet<KeyValue> set,
final long logCacheFlushId)
throws IOException {
StoreFile.Writer writer = null;
long flushed = 0;
// Don't flush if there are no entries.
if (set.size() == 0) {
return null;
}
long oldestTimestamp = System.currentTimeMillis() - ttl;
// TODO: We can fail in the below block before we complete adding this
// flush to list of store files. Add cleanup of anything put on filesystem
// if we fail.
synchronized (flushLock) {
// A. Write the map out to the disk
writer = createWriterInTmp(set.size());
int entries = 0;
try {
for (KeyValue kv: set) {
if (!isExpired(kv, oldestTimestamp)) {
writer.append(kv);
entries++;
flushed += this.memstore.heapSizeChange(kv, true);
}
}
} finally {
// Write out the log sequence number that corresponds to this output
// hfile. The hfile is current up to and including logCacheFlushId.
writer.appendMetadata(logCacheFlushId, false);
writer.close();
}
}
// Write-out finished successfully, move into the right spot
Path dstPath = StoreFile.getUniqueFile(fs, homedir);
LOG.info("Renaming flushed file at " + writer.getPath() + " to " + dstPath);
fs.rename(writer.getPath(), dstPath);
StoreFile sf = new StoreFile(this.fs, dstPath, blockcache,
this.conf, this.family.getBloomFilterType(), this.inMemory);
Reader r = sf.createReader();
this.storeSize += r.length();
if(LOG.isInfoEnabled()) {
LOG.info("Added " + sf + ", entries=" + r.getEntries() +
", sequenceid=" + logCacheFlushId +
", memsize=" + StringUtils.humanReadableInt(flushed) +
", filesize=" + StringUtils.humanReadableInt(r.length()) +
" to " + this.region.regionInfo.getRegionNameAsString());
}
return sf;
}
/*
* @return Writer for a new StoreFile in the tmp dir.
*/
private StoreFile.Writer createWriterInTmp(int maxKeyCount)
throws IOException {
return StoreFile.createWriter(this.fs, region.getTmpDir(), this.blocksize,
this.compression, this.comparator, this.conf,
this.family.getBloomFilterType(), maxKeyCount);
}
/*
* Change storefiles adding into place the Reader produced by this new flush.
* @param sf
* @param set That was used to make the passed file <code>p</code>.
* @throws IOException
* @return Whether compaction is required.
*/
private boolean updateStorefiles(final StoreFile sf,
final SortedSet<KeyValue> set)
throws IOException {
this.lock.writeLock().lock();
try {
ArrayList<StoreFile> newList = new ArrayList<StoreFile>(storefiles);
newList.add(sf);
storefiles = ImmutableList.copyOf(newList);
this.memstore.clearSnapshot(set);
// Tell listeners of the change in readers.
notifyChangedReadersObservers();
return this.storefiles.size() >= this.compactionThreshold;
} finally {
this.lock.writeLock().unlock();
}
}
/*
* Notify all observers that set of Readers has changed.
* @throws IOException
*/
private void notifyChangedReadersObservers() throws IOException {
for (ChangedReadersObserver o: this.changedReaderObservers) {
o.updateReaders();
}
}
/*
* @param o Observer who wants to know about changes in set of Readers
*/
void addChangedReaderObserver(ChangedReadersObserver o) {
this.changedReaderObservers.add(o);
}
/*
* @param o Observer no longer interested in changes in set of Readers.
*/
void deleteChangedReaderObserver(ChangedReadersObserver o) {
if (!this.changedReaderObservers.remove(o)) {
LOG.warn("Not in set" + o);
}
}
//////////////////////////////////////////////////////////////////////////////
// Compaction
//////////////////////////////////////////////////////////////////////////////
/**
* Compact the StoreFiles. This method may take some time, so the calling
* thread must be able to block for long periods.
*
* <p>During this time, the Store can work as usual, getting values from
* StoreFiles and writing new StoreFiles from the memstore.
*
* Existing StoreFiles are not destroyed until the new compacted StoreFile is
* completely written-out to disk.
*
* <p>The compactLock prevents multiple simultaneous compactions.
* The structureLock prevents us from interfering with other write operations.
*
* <p>We don't want to hold the structureLock for the whole time, as a compact()
* can be lengthy and we want to allow cache-flushes during this period.
*
* @param mc True to force a major compaction regardless of thresholds
* @return row to split around if a split is needed, null otherwise
* @throws IOException
*/
StoreSize compact(final boolean mc) throws IOException {
boolean forceSplit = this.region.shouldSplit(false);
boolean majorcompaction = mc;
synchronized (compactLock) {
// filesToCompact are sorted oldest to newest.
List<StoreFile> filesToCompact = this.storefiles;
if (filesToCompact.isEmpty()) {
LOG.debug(this.storeNameStr + ": no store files to compact");
return null;
}
// Max-sequenceID is the last key of the storefiles TreeMap
long maxId = StoreFile.getMaxSequenceIdInList(storefiles);
// Check to see if we need to do a major compaction on this region.
// If so, change doMajorCompaction to true to skip the incremental
// compacting below. Only check if doMajorCompaction is not true.
if (!majorcompaction) {
majorcompaction = isMajorCompaction(filesToCompact);
}
boolean references = hasReferences(filesToCompact);
if (!majorcompaction && !references &&
(forceSplit || (filesToCompact.size() < compactionThreshold))) {
return checkSplit(forceSplit);
}
// HBASE-745, preparing all store file sizes for incremental compacting
// selection.
int countOfFiles = filesToCompact.size();
long totalSize = 0;
long [] fileSizes = new long[countOfFiles];
long skipped = 0;
int point = 0;
for (int i = 0; i < countOfFiles; i++) {
StoreFile file = filesToCompact.get(i);
Path path = file.getPath();
if (path == null) {
LOG.warn("Path is null for " + file);
return null;
}
Reader r = file.getReader();
if (r == null) {
LOG.warn("StoreFile " + file + " has a null Reader");
return null;
}
long len = file.getReader().length();
fileSizes[i] = len;
totalSize += len;
}
if (!majorcompaction && !references) {
// Here we select files for incremental compaction.
// The rule is: if the largest(oldest) one is more than twice the
// size of the second, skip the largest, and continue to next...,
// until we meet the compactionThreshold limit.
// A problem with the above heuristic is that we could go through all of
// filesToCompact and the above condition could hold for all files and
// we'd end up with nothing to compact. To protect against this, we'll
// compact the tail -- up to the last 4 files -- of filesToCompact
// regardless.
int tail = Math.min(countOfFiles, 4);
for (point = 0; point < (countOfFiles - tail); point++) {
if (((fileSizes[point] < fileSizes[point + 1] * 2) &&
(countOfFiles - point) <= maxFilesToCompact)) {
break;
}
skipped += fileSizes[point];
}
filesToCompact = new ArrayList<StoreFile>(filesToCompact.subList(point,
countOfFiles));
if (filesToCompact.size() <= 1) {
if (LOG.isDebugEnabled()) {
LOG.debug("Skipped compaction of 1 file; compaction size of " +
this.storeNameStr + ": " +
StringUtils.humanReadableInt(totalSize) + "; Skipped " + point +
" files, size: " + skipped);
}
return checkSplit(forceSplit);
}
if (LOG.isDebugEnabled()) {
LOG.debug("Compaction size of " + this.storeNameStr + ": " +
StringUtils.humanReadableInt(totalSize) + "; Skipped " + point +
" file(s), size: " + skipped);
}
}
// Ready to go. Have list of files to compact.
LOG.info("Started compaction of " + filesToCompact.size() + " file(s) in " +
this.storeNameStr + " of " + this.region.getRegionInfo().getRegionNameAsString() +
(references? ", hasReferences=true,": " ") + " into " +
region.getTmpDir() + ", seqid=" + maxId);
HFile.Writer writer = compact(filesToCompact, majorcompaction, maxId);
// Move the compaction into place.
StoreFile sf = completeCompaction(filesToCompact, writer);
if (LOG.isInfoEnabled()) {
LOG.info("Completed" + (majorcompaction? " major ": " ") +
"compaction of " + filesToCompact.size() + " file(s) in " +
this.storeNameStr + " of " + this.region.getRegionInfo().getRegionNameAsString() +
"; new storefile is " + (sf == null? "none": sf.toString()) +
"; store size is " + StringUtils.humanReadableInt(storeSize));
}
}
return checkSplit(forceSplit);
}
/*
* @param files
* @return True if any of the files in <code>files</code> are References.
*/
private boolean hasReferences(Collection<StoreFile> files) {
if (files != null && files.size() > 0) {
for (StoreFile hsf: files) {
if (hsf.isReference()) {
return true;
}
}
}
return false;
}
/*
* Gets lowest timestamp from files in a dir
*
* @param fs
* @param dir
* @throws IOException
*/
private static long getLowestTimestamp(FileSystem fs, Path dir)
throws IOException {
FileStatus[] stats = fs.listStatus(dir);
if (stats == null || stats.length == 0) {
return 0l;
}
long lowTimestamp = Long.MAX_VALUE;
for (int i = 0; i < stats.length; i++) {
long timestamp = stats[i].getModificationTime();
if (timestamp < lowTimestamp){
lowTimestamp = timestamp;
}
}
return lowTimestamp;
}
/*
* @return True if we should run a major compaction.
*/
boolean isMajorCompaction() throws IOException {
return isMajorCompaction(storefiles);
}
/*
* @param filesToCompact Files to compact. Can be null.
* @return True if we should run a major compaction.
*/
private boolean isMajorCompaction(final List<StoreFile> filesToCompact)
throws IOException {
boolean result = false;
if (filesToCompact == null || filesToCompact.isEmpty() ||
majorCompactionTime == 0) {
return result;
}
long lowTimestamp = getLowestTimestamp(fs,
filesToCompact.get(0).getPath().getParent());
long now = System.currentTimeMillis();
if (lowTimestamp > 0l && lowTimestamp < (now - this.majorCompactionTime)) {
// Major compaction time has elapsed.
long elapsedTime = now - lowTimestamp;
if (filesToCompact.size() == 1 &&
filesToCompact.get(0).isMajorCompaction() &&
(this.ttl == HConstants.FOREVER || elapsedTime < this.ttl)) {
if (LOG.isDebugEnabled()) {
LOG.debug("Skipping major compaction of " + this.storeNameStr +
" because one (major) compacted file only and elapsedTime " +
elapsedTime + "ms is < ttl=" + this.ttl);
}
} else {
if (LOG.isDebugEnabled()) {
LOG.debug("Major compaction triggered on store " + this.storeNameStr +
"; time since last major compaction " + (now - lowTimestamp) + "ms");
}
result = true;
}
}
return result;
}
/**
* Do a minor/major compaction. Uses the scan infrastructure to make it easy.
*
* @param filesToCompact which files to compact
* @param majorCompaction true to major compact (prune all deletes, max versions, etc)
* @param maxId Readers maximum sequence id.
* @return Product of compaction or null if all cells expired or deleted and
* nothing made it through the compaction.
* @throws IOException
*/
private HFile.Writer compact(final List<StoreFile> filesToCompact,
final boolean majorCompaction, final long maxId)
throws IOException {
// calculate maximum key count after compaction (for blooms)
int maxKeyCount = 0;
for (StoreFile file : filesToCompact) {
StoreFile.Reader r = file.getReader();
if (r != null) {
// NOTE: getFilterEntries could cause under-sized blooms if the user
// switches bloom type (e.g. from ROW to ROWCOL)
maxKeyCount += (r.getBloomFilterType() == family.getBloomFilterType())
? r.getFilterEntries() : r.getEntries();
}
}
// For each file, obtain a scanner:
List<StoreFileScanner> scanners = StoreFileScanner
.getScannersForStoreFiles(filesToCompact, false, false);
// Make the instantiation lazy in case compaction produces no product; i.e.
// where all source cells are expired or deleted.
StoreFile.Writer writer = null;
try {
if (majorCompaction) {
InternalScanner scanner = null;
try {
Scan scan = new Scan();
scan.setMaxVersions(family.getMaxVersions());
scanner = new StoreScanner(this, scan, scanners);
// since scanner.next() can return 'false' but still be delivering data,
// we have to use a do/while loop.
ArrayList<KeyValue> kvs = new ArrayList<KeyValue>();
while (scanner.next(kvs)) {
// output to writer:
for (KeyValue kv : kvs) {
if (writer == null) {
writer = createWriterInTmp(maxKeyCount);
}
writer.append(kv);
}
kvs.clear();
}
} finally {
if (scanner != null) {
scanner.close();
}
}
} else {
MinorCompactingStoreScanner scanner = null;
try {
scanner = new MinorCompactingStoreScanner(this, scanners);
writer = createWriterInTmp(maxKeyCount);
while (scanner.next(writer)) {
// Nothing to do
}
} finally {
if (scanner != null)
scanner.close();
}
}
} finally {
if (writer != null) {
writer.appendMetadata(maxId, majorCompaction);
writer.close();
}
}
return writer;
}
/*
* It's assumed that the compactLock will be acquired prior to calling this
* method! Otherwise, it is not thread-safe!
*
* <p>It works by processing a compaction that's been written to disk.
*
* <p>It is usually invoked at the end of a compaction, but might also be
* invoked at HStore startup, if the prior execution died midway through.
*
* <p>Moving the compacted TreeMap into place means:
* <pre>
* 1) Moving the new compacted StoreFile into place
* 2) Unload all replaced StoreFile, close and collect list to delete.
* 3) Loading the new TreeMap.
* 4) Compute new store size
* </pre>
*
* @param compactedFiles list of files that were compacted
* @param compactedFile StoreFile that is the result of the compaction
* @return StoreFile created. May be null.
* @throws IOException
*/
private StoreFile completeCompaction(final List<StoreFile> compactedFiles,
final HFile.Writer compactedFile)
throws IOException {
// 1. Moving the new files into place -- if there is a new file (may not
// be if all cells were expired or deleted).
StoreFile result = null;
if (compactedFile != null) {
Path p = null;
try {
p = StoreFile.rename(this.fs, compactedFile.getPath(),
StoreFile.getRandomFilename(fs, this.homedir));
} catch (IOException e) {
LOG.error("Failed move of compacted file " + compactedFile.getPath(), e);
return null;
}
result = new StoreFile(this.fs, p, blockcache, this.conf,
this.family.getBloomFilterType(), this.inMemory);
result.createReader();
}
this.lock.writeLock().lock();
try {
try {
// 2. Unloading
// 3. Loading the new TreeMap.
// Change this.storefiles so it reflects new state but do not
// delete old store files until we have sent out notification of
// change in case old files are still being accessed by outstanding
// scanners.
ArrayList<StoreFile> newStoreFiles = new ArrayList<StoreFile>();
for (StoreFile sf : storefiles) {
if (!compactedFiles.contains(sf)) {
newStoreFiles.add(sf);
}
}
// If a StoreFile result, move it into place. May be null.
if (result != null) {
newStoreFiles.add(result);
}
this.storefiles = ImmutableList.copyOf(newStoreFiles);
// Tell observers that list of StoreFiles has changed.
notifyChangedReadersObservers();
// Finally, delete old store files.
for (StoreFile hsf: compactedFiles) {
hsf.deleteReader();
}
} catch (IOException e) {
e = RemoteExceptionHandler.checkIOException(e);
LOG.error("Failed replacing compacted files in " + this.storeNameStr +
". Compacted file is " + (result == null? "none": result.toString()) +
". Files replaced " + compactedFiles.toString() +
" some of which may have been already removed", e);
}
// 4. Compute new store size
this.storeSize = 0L;
for (StoreFile hsf : this.storefiles) {
Reader r = hsf.getReader();
if (r == null) {
LOG.warn("StoreFile " + hsf + " has a null Reader");
continue;
}
this.storeSize += r.length();
}
} finally {
this.lock.writeLock().unlock();
}
return result;
}
// ////////////////////////////////////////////////////////////////////////////
// Accessors.
// (This is the only section that is directly useful!)
//////////////////////////////////////////////////////////////////////////////
/**
* @return the number of files in this store
*/
public int getNumberOfstorefiles() {
return this.storefiles.size();
}
/*
* @param wantedVersions How many versions were asked for.
* @return wantedVersions or this families' {@link HConstants#VERSIONS}.
*/
int versionsToReturn(final int wantedVersions) {
if (wantedVersions <= 0) {
throw new IllegalArgumentException("Number of versions must be > 0");
}
// Make sure we do not return more than maximum versions for this store.
int maxVersions = this.family.getMaxVersions();
return wantedVersions > maxVersions ? maxVersions: wantedVersions;
}
static void expiredOrDeleted(final Set<KeyValue> set, final KeyValue kv) {
boolean b = set.remove(kv);
if (LOG.isDebugEnabled()) {
LOG.debug(kv.toString() + " expired: " + b);
}
}
static boolean isExpired(final KeyValue key, final long oldestTimestamp) {
return key.getTimestamp() < oldestTimestamp;
}
/**
* Find the key that matches <i>row</i> exactly, or the one that immediately
* preceeds it. WARNING: Only use this method on a table where writes occur
* with strictly increasing timestamps. This method assumes this pattern of
* writes in order to make it reasonably performant. Also our search is
* dependent on the axiom that deletes are for cells that are in the container
* that follows whether a memstore snapshot or a storefile, not for the
* current container: i.e. we'll see deletes before we come across cells we
* are to delete. Presumption is that the memstore#kvset is processed before
* memstore#snapshot and so on.
* @param kv First possible item on targeted row; i.e. empty columns, latest
* timestamp and maximum type.
* @return Found keyvalue or null if none found.
* @throws IOException
*/
KeyValue getRowKeyAtOrBefore(final KeyValue kv)
throws IOException {
GetClosestRowBeforeTracker state = new GetClosestRowBeforeTracker(
this.comparator, kv, this.ttl, this.region.getRegionInfo().isMetaRegion());
this.lock.readLock().lock();
try {
// First go to the memstore. Pick up deletes and candidates.
this.memstore.getRowKeyAtOrBefore(state);
// Check if match, if we got a candidate on the asked for 'kv' row.
// Process each store file. Run through from newest to oldest.
for (StoreFile sf : Iterables.reverse(storefiles)) {
// Update the candidate keys from the current map file
rowAtOrBeforeFromStoreFile(sf, state);
}
return state.getCandidate();
} finally {
this.lock.readLock().unlock();
}
}
/*
* Check an individual MapFile for the row at or before a given row.
* @param f
* @param state
* @throws IOException
*/
private void rowAtOrBeforeFromStoreFile(final StoreFile f,
final GetClosestRowBeforeTracker state)
throws IOException {
Reader r = f.getReader();
if (r == null) {
LOG.warn("StoreFile " + f + " has a null Reader");
return;
}
// TODO: Cache these keys rather than make each time?
byte [] fk = r.getFirstKey();
KeyValue firstKV = KeyValue.createKeyValueFromKey(fk, 0, fk.length);
byte [] lk = r.getLastKey();
KeyValue lastKV = KeyValue.createKeyValueFromKey(lk, 0, lk.length);
KeyValue firstOnRow = state.getTargetKey();
if (this.comparator.compareRows(lastKV, firstOnRow) < 0) {
// If last key in file is not of the target table, no candidates in this
// file. Return.
if (!state.isTargetTable(lastKV)) return;
// If the row we're looking for is past the end of file, set search key to
// last key. TODO: Cache last and first key rather than make each time.
firstOnRow = new KeyValue(lastKV.getRow(), HConstants.LATEST_TIMESTAMP);
}
// Get a scanner that caches blocks and that uses pread.
HFileScanner scanner = r.getScanner(true, true);
// Seek scanner. If can't seek it, return.
if (!seekToScanner(scanner, firstOnRow, firstKV)) return;
// If we found candidate on firstOnRow, just return. THIS WILL NEVER HAPPEN!
// Unlikely that there'll be an instance of actual first row in table.
if (walkForwardInSingleRow(scanner, firstOnRow, state)) return;
// If here, need to start backing up.
while (scanner.seekBefore(firstOnRow.getBuffer(), firstOnRow.getKeyOffset(),
firstOnRow.getKeyLength())) {
KeyValue kv = scanner.getKeyValue();
if (!state.isTargetTable(kv)) break;
if (!state.isBetterCandidate(kv)) break;
// Make new first on row.
firstOnRow = new KeyValue(kv.getRow(), HConstants.LATEST_TIMESTAMP);
// Seek scanner. If can't seek it, break.
if (!seekToScanner(scanner, firstOnRow, firstKV)) break;
// If we find something, break;
if (walkForwardInSingleRow(scanner, firstOnRow, state)) break;
}
}
/*
* Seek the file scanner to firstOnRow or first entry in file.
* @param scanner
* @param firstOnRow
* @param firstKV
* @return True if we successfully seeked scanner.
* @throws IOException
*/
private boolean seekToScanner(final HFileScanner scanner,
final KeyValue firstOnRow, final KeyValue firstKV)
throws IOException {
KeyValue kv = firstOnRow;
// If firstOnRow < firstKV, set to firstKV
if (this.comparator.compareRows(firstKV, firstOnRow) == 0) kv = firstKV;
int result = scanner.seekTo(kv.getBuffer(), kv.getKeyOffset(),
kv.getKeyLength());
return result >= 0;
}
/*
* When we come in here, we are probably at the kv just before we break into
* the row that firstOnRow is on. Usually need to increment one time to get
* on to the row we are interested in.
* @param scanner
* @param firstOnRow
* @param state
* @return True we found a candidate.
* @throws IOException
*/
private boolean walkForwardInSingleRow(final HFileScanner scanner,
final KeyValue firstOnRow, final GetClosestRowBeforeTracker state)
throws IOException {
boolean foundCandidate = false;
do {
KeyValue kv = scanner.getKeyValue();
// If we are not in the row, skip.
if (this.comparator.compareRows(kv, firstOnRow) < 0) continue;
// Did we go beyond the target row? If so break.
if (state.isTooFar(kv, firstOnRow)) break;
if (state.isExpired(kv)) {
continue;
}
// If we added something, this row is a contender. break.
if (state.handle(kv)) {
foundCandidate = true;
break;
}
} while(scanner.next());
return foundCandidate;
}
/**
* Determines if HStore can be split
* @param force Whether to force a split or not.
* @return a StoreSize if store can be split, null otherwise.
*/
StoreSize checkSplit(final boolean force) {
this.lock.readLock().lock();
try {
// Iterate through all store files
if (this.storefiles.isEmpty()) {
return null;
}
if (!force && (storeSize < this.desiredMaxFileSize)) {
return null;
}
if (this.region.getRegionInfo().isMetaRegion()) {
if (force) {
LOG.warn("Cannot split meta regions in HBase 0.20");
}
return null;
}
// Not splitable if we find a reference store file present in the store.
boolean splitable = true;
long maxSize = 0L;
StoreFile largestSf = null;
for (StoreFile sf : storefiles) {
if (splitable) {
splitable = !sf.isReference();
if (!splitable) {
// RETURN IN MIDDLE OF FUNCTION!!! If not splitable, just return.
if (LOG.isDebugEnabled()) {
LOG.debug(sf + " is not splittable");
}
return null;
}
}
Reader r = sf.getReader();
if (r == null) {
LOG.warn("Storefile " + sf + " Reader is null");
continue;
}
long size = r.length();
if (size > maxSize) {
// This is the largest one so far
maxSize = size;
largestSf = sf;
}
}
HFile.Reader r = largestSf.getReader();
if (r == null) {
LOG.warn("Storefile " + largestSf + " Reader is null");
return null;
}
// Get first, last, and mid keys. Midkey is the key that starts block
// in middle of hfile. Has column and timestamp. Need to return just
// the row we want to split on as midkey.
byte [] midkey = r.midkey();
if (midkey != null) {
KeyValue mk = KeyValue.createKeyValueFromKey(midkey, 0, midkey.length);
byte [] fk = r.getFirstKey();
KeyValue firstKey = KeyValue.createKeyValueFromKey(fk, 0, fk.length);
byte [] lk = r.getLastKey();
KeyValue lastKey = KeyValue.createKeyValueFromKey(lk, 0, lk.length);
// if the midkey is the same as the first and last keys, then we cannot
// (ever) split this region.
if (this.comparator.compareRows(mk, firstKey) == 0 &&
this.comparator.compareRows(mk, lastKey) == 0) {
if (LOG.isDebugEnabled()) {
LOG.debug("cannot split because midkey is the same as first or " +
"last row");
}
return null;
}
return new StoreSize(maxSize, mk.getRow());
}
} catch(IOException e) {
LOG.warn("Failed getting store size for " + this.storeNameStr, e);
} finally {
this.lock.readLock().unlock();
}
return null;
}
/** @return aggregate size of HStore */
public long getSize() {
return storeSize;
}
//////////////////////////////////////////////////////////////////////////////
// File administration
//////////////////////////////////////////////////////////////////////////////
/**
* Return a scanner for both the memstore and the HStore files
* @throws IOException
*/
protected KeyValueScanner getScanner(Scan scan,
final NavigableSet<byte []> targetCols) throws IOException {
lock.readLock().lock();
try {
return new StoreScanner(this, scan, targetCols);
} finally {
lock.readLock().unlock();
}
}
@Override
public String toString() {
return this.storeNameStr;
}
/**
* @return Count of store files
*/
int getStorefilesCount() {
return this.storefiles.size();
}
/**
* @return The size of the store files, in bytes.
*/
long getStorefilesSize() {
long size = 0;
for (StoreFile s: storefiles) {
Reader r = s.getReader();
if (r == null) {
LOG.warn("StoreFile " + s + " has a null Reader");
continue;
}
size += r.length();
}
return size;
}
/**
* @return The size of the store file indexes, in bytes.
*/
long getStorefilesIndexSize() {
long size = 0;
for (StoreFile s: storefiles) {
Reader r = s.getReader();
if (r == null) {
LOG.warn("StoreFile " + s + " has a null Reader");
continue;
}
size += r.indexSize();
}
return size;
}
/**
* Datastructure that holds size and row to split a file around.
* TODO: Take a KeyValue rather than row.
*/
static class StoreSize {
private final long size;
private final byte [] row;
StoreSize(long size, byte [] row) {
this.size = size;
this.row = row;
}
/* @return the size */
long getSize() {
return size;
}
byte [] getSplitRow() {
return this.row;
}
}
HRegion getHRegion() {
return this.region;
}
HRegionInfo getHRegionInfo() {
return this.region.regionInfo;
}
/**
* Convenience method that implements the old MapFile.getClosest on top of
* HFile Scanners. getClosest used seek to the asked-for key or just after
* (HFile seeks to the key or just before).
* @param s Scanner to use
* @param kv Key to find.
* @return True if we were able to seek the scanner to <code>b</code> or to
* the key just after.
* @throws IOException
*/
static boolean getClosest(final HFileScanner s, final KeyValue kv)
throws IOException {
// Pass offsets to key content of a KeyValue; thats whats in the hfile index.
int result = s.seekTo(kv.getBuffer(), kv.getKeyOffset(), kv.getKeyLength());
if (result < 0) {
// Not in file. Will the first key do?
if (!s.seekTo()) {
return false;
}
} else if (result > 0) {
// Less than what was asked for but maybe < because we're asking for
// r/c/HConstants.LATEST_TIMESTAMP -- what was returned was r/c-1/SOME_TS...
// A next will get us a r/c/SOME_TS.
if (!s.next()) {
return false;
}
}
return true;
}
/**
* Retrieve results from this store given the specified Get parameters.
* @param get Get operation
* @param columns List of columns to match, can be empty (not null)
* @param result List to add results to
* @throws IOException
*/
public void get(Get get, NavigableSet<byte[]> columns, List<KeyValue> result)
throws IOException {
KeyComparator keyComparator = this.comparator.getRawComparator();
// Column matching and version enforcement
QueryMatcher matcher = new QueryMatcher(get, this.family.getName(), columns,
this.ttl, keyComparator, versionsToReturn(get.getMaxVersions()));
this.lock.readLock().lock();
try {
// Read from memstore
if(this.memstore.get(matcher, result)) {
// Received early-out from memstore
return;
}
// Check if we even have storefiles
if (this.storefiles.isEmpty()) {
return;
}
// Get storefiles for this store
List<HFileScanner> storefileScanners = new ArrayList<HFileScanner>();
for (StoreFile sf : Iterables.reverse(this.storefiles)) {
HFile.Reader r = sf.getReader();
if (r == null) {
LOG.warn("StoreFile " + sf + " has a null Reader");
continue;
}
// Get a scanner that caches the block and uses pread
storefileScanners.add(r.getScanner(true, true));
}
// StoreFileGetScan will handle reading this store's storefiles
StoreFileGetScan scanner = new StoreFileGetScan(storefileScanners, matcher);
// Run a GET scan and put results into the specified list
scanner.get(result);
} finally {
this.lock.readLock().unlock();
}
}
/**
* Increments the value for the given row/family/qualifier.
*
* This function will always be seen as atomic by other readers
* because it only puts a single KV to memstore. Thus no
* read/write control necessary.
*
* @param row
* @param f
* @param qualifier
* @param newValue the new value to set into memstore
* @return memstore size delta
* @throws IOException
*/
public long updateColumnValue(byte [] row, byte [] f,
byte [] qualifier, long newValue)
throws IOException {
List<KeyValue> result = new ArrayList<KeyValue>();
KeyComparator keyComparator = this.comparator.getRawComparator();
KeyValue kv = null;
// Setting up the QueryMatcher
Get get = new Get(row);
NavigableSet<byte[]> qualifiers =
new TreeSet<byte[]>(Bytes.BYTES_COMPARATOR);
qualifiers.add(qualifier);
QueryMatcher matcher = new QueryMatcher(get, f, qualifiers, this.ttl,
keyComparator, 1);
// lock memstore snapshot for this critical section:
this.lock.readLock().lock();
memstore.readLockLock();
try {
int memstoreCode = this.memstore.getWithCode(matcher, result);
if (memstoreCode != 0) {
// was in memstore (or snapshot)
kv = result.get(0).clone();
byte [] buffer = kv.getBuffer();
int valueOffset = kv.getValueOffset();
Bytes.putBytes(buffer, valueOffset, Bytes.toBytes(newValue), 0,
Bytes.SIZEOF_LONG);
if (memstoreCode == 2) {
// from snapshot, assign new TS
long currTs = System.currentTimeMillis();
if (currTs == kv.getTimestamp()) {
currTs++; // unlikely but catastrophic
}
Bytes.putBytes(buffer, kv.getTimestampOffset(),
Bytes.toBytes(currTs), 0, Bytes.SIZEOF_LONG);
}
} else {
kv = new KeyValue(row, f, qualifier,
System.currentTimeMillis(),
Bytes.toBytes(newValue));
}
return add(kv);
// end lock
} finally {
memstore.readLockUnlock();
this.lock.readLock().unlock();
}
}
public StoreFlusher getStoreFlusher(long cacheFlushId) {
return new StoreFlusherImpl(cacheFlushId);
}
private class StoreFlusherImpl implements StoreFlusher {
private long cacheFlushId;
private SortedSet<KeyValue> snapshot;
private StoreFile storeFile;
private StoreFlusherImpl(long cacheFlushId) {
this.cacheFlushId = cacheFlushId;
}
@Override
public void prepare() {
memstore.snapshot();
this.snapshot = memstore.getSnapshot();
}
@Override
public void flushCache() throws IOException {
storeFile = Store.this.flushCache(cacheFlushId, snapshot);
}
@Override
public boolean commit() throws IOException {
if (storeFile == null) {
return false;
}
// Add new file to store files. Clear snapshot too while we have
// the Store write lock.
return Store.this.updateStorefiles(storeFile, snapshot);
}
}
/**
* See if there's too much store files in this store
* @return true if number of store files is greater than
* the number defined in compactionThreshold
*/
public boolean hasTooManyStoreFiles() {
return this.storefiles.size() > this.compactionThreshold;
}
public static final long FIXED_OVERHEAD = ClassSize.align(
ClassSize.OBJECT + (14 * ClassSize.REFERENCE) +
(4 * Bytes.SIZEOF_LONG) + (3 * Bytes.SIZEOF_INT) + (Bytes.SIZEOF_BOOLEAN * 2));
public static final long DEEP_OVERHEAD = ClassSize.align(FIXED_OVERHEAD +
ClassSize.OBJECT + ClassSize.REENTRANT_LOCK +
ClassSize.CONCURRENT_SKIPLISTMAP +
ClassSize.CONCURRENT_SKIPLISTMAP_ENTRY + ClassSize.OBJECT);
@Override
public long heapSize() {
return DEEP_OVERHEAD + this.memstore.heapSize();
}
}