/**
* 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.compactions;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.KeyValueUtil;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.io.compress.Compression;
import org.apache.hadoop.hbase.io.hfile.HFile.FileInfo;
import org.apache.hadoop.hbase.io.hfile.HFileWriterV2;
import org.apache.hadoop.hbase.regionserver.HStore;
import org.apache.hadoop.hbase.regionserver.InternalScanner;
import org.apache.hadoop.hbase.regionserver.ScanType;
import org.apache.hadoop.hbase.regionserver.Store;
import org.apache.hadoop.hbase.regionserver.StoreFile;
import org.apache.hadoop.hbase.regionserver.StoreFileScanner;
import org.apache.hadoop.hbase.regionserver.StoreScanner;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.util.StringUtils;
/**
* A compactor is a compaction algorithm associated a given policy. Base class also contains
* reusable parts for implementing compactors (what is common and what isn't is evolving).
*/
@InterfaceAudience.Private
public abstract class Compactor {
private static final Log LOG = LogFactory.getLog(Compactor.class);
protected CompactionProgress progress;
protected Configuration conf;
protected Store store;
private int compactionKVMax;
protected Compression.Algorithm compactionCompression;
//TODO: depending on Store is not good but, realistically, all compactors currently do.
Compactor(final Configuration conf, final Store store) {
this.conf = conf;
this.store = store;
this.compactionKVMax =
this.conf.getInt(HConstants.COMPACTION_KV_MAX, HConstants.COMPACTION_KV_MAX_DEFAULT);
this.compactionCompression = (this.store.getFamily() == null) ?
Compression.Algorithm.NONE : this.store.getFamily().getCompactionCompression();
}
/**
* TODO: Replace this with CellOutputStream when StoreFile.Writer uses cells.
*/
public interface CellSink {
void append(KeyValue kv) throws IOException;
}
public CompactionProgress getProgress() {
return this.progress;
}
/** The sole reason this class exists is that java has no ref/out/pointer parameters. */
protected static class FileDetails {
/** Maximum key count after compaction (for blooms) */
public long maxKeyCount = 0;
/** Earliest put timestamp if major compaction */
public long earliestPutTs = HConstants.LATEST_TIMESTAMP;
/** The last key in the files we're compacting. */
public long maxSeqId = 0;
/** Latest memstore read point found in any of the involved files */
public long maxMVCCReadpoint = 0;
/** Max tags length**/
public int maxTagsLength = 0;
}
/**
* Extracts some details about the files to compact that are commonly needed by compactors.
* @param filesToCompact Files.
* @param calculatePutTs Whether earliest put TS is needed.
* @return The result.
*/
protected FileDetails getFileDetails(
Collection<StoreFile> filesToCompact, boolean calculatePutTs) throws IOException {
FileDetails fd = new FileDetails();
for (StoreFile file : filesToCompact) {
long seqNum = file.getMaxSequenceId();
fd.maxSeqId = Math.max(fd.maxSeqId, seqNum);
StoreFile.Reader r = file.getReader();
if (r == null) {
LOG.warn("Null reader for " + file.getPath());
continue;
}
// NOTE: getFilterEntries could cause under-sized blooms if the user
// switches bloom type (e.g. from ROW to ROWCOL)
long keyCount = (r.getBloomFilterType() == store.getFamily().getBloomFilterType())
? r.getFilterEntries() : r.getEntries();
fd.maxKeyCount += keyCount;
// calculate the latest MVCC readpoint in any of the involved store files
Map<byte[], byte[]> fileInfo = r.loadFileInfo();
byte tmp[] = fileInfo.get(HFileWriterV2.MAX_MEMSTORE_TS_KEY);
if (tmp != null) {
fd.maxMVCCReadpoint = Math.max(fd.maxMVCCReadpoint, Bytes.toLong(tmp));
}
tmp = fileInfo.get(FileInfo.MAX_TAGS_LEN);
if (tmp != null) {
fd.maxTagsLength = Math.max(fd.maxTagsLength, Bytes.toInt(tmp));
}
// If required, calculate the earliest put timestamp of all involved storefiles.
// This is used to remove family delete marker during compaction.
long earliestPutTs = 0;
if (calculatePutTs) {
tmp = fileInfo.get(StoreFile.EARLIEST_PUT_TS);
if (tmp == null) {
// There's a file with no information, must be an old one
// assume we have very old puts
fd.earliestPutTs = earliestPutTs = HConstants.OLDEST_TIMESTAMP;
} else {
earliestPutTs = Bytes.toLong(tmp);
fd.earliestPutTs = Math.min(fd.earliestPutTs, earliestPutTs);
}
}
if (LOG.isDebugEnabled()) {
LOG.debug("Compacting " + file +
", keycount=" + keyCount +
", bloomtype=" + r.getBloomFilterType().toString() +
", size=" + StringUtils.humanReadableInt(r.length()) +
", encoding=" + r.getHFileReader().getDataBlockEncoding() +
", seqNum=" + seqNum +
(calculatePutTs ? ", earliestPutTs=" + earliestPutTs: ""));
}
}
return fd;
}
/**
* Creates file scanners for compaction.
* @param filesToCompact Files.
* @return Scanners.
*/
protected List<StoreFileScanner> createFileScanners(
final Collection<StoreFile> filesToCompact, long smallestReadPoint) throws IOException {
return StoreFileScanner.getScannersForStoreFiles(filesToCompact, false, false, true,
smallestReadPoint);
}
protected long getSmallestReadPoint() {
return store.getSmallestReadPoint();
}
/**
* Calls coprocessor, if any, to create compaction scanner - before normal scanner creation.
* @param request Compaction request.
* @param scanType Scan type.
* @param earliestPutTs Earliest put ts.
* @param scanners File scanners for compaction files.
* @return Scanner override by coprocessor; null if not overriding.
*/
protected InternalScanner preCreateCoprocScanner(final CompactionRequest request,
ScanType scanType, long earliestPutTs, List<StoreFileScanner> scanners) throws IOException {
if (store.getCoprocessorHost() == null) return null;
return store.getCoprocessorHost()
.preCompactScannerOpen(store, scanners, scanType, earliestPutTs, request);
}
/**
* Calls coprocessor, if any, to create scanners - after normal scanner creation.
* @param request Compaction request.
* @param scanType Scan type.
* @param scanner The default scanner created for compaction.
* @return Scanner scanner to use (usually the default); null if compaction should not proceed.
*/
protected InternalScanner postCreateCoprocScanner(final CompactionRequest request,
ScanType scanType, InternalScanner scanner) throws IOException {
if (store.getCoprocessorHost() == null) return scanner;
return store.getCoprocessorHost().preCompact(store, scanner, scanType, request);
}
/**
* Performs the compaction.
* @param scanner Where to read from.
* @param writer Where to write to.
* @param smallestReadPoint Smallest read point.
* @return Whether compaction ended; false if it was interrupted for some reason.
*/
protected boolean performCompaction(InternalScanner scanner,
CellSink writer, long smallestReadPoint) throws IOException {
int bytesWritten = 0;
// Since scanner.next() can return 'false' but still be delivering data,
// we have to use a do/while loop.
List<Cell> kvs = new ArrayList<Cell>();
// Limit to "hbase.hstore.compaction.kv.max" (default 10) to avoid OOME
int closeCheckInterval = HStore.getCloseCheckInterval();
boolean hasMore;
do {
hasMore = scanner.next(kvs, compactionKVMax);
// output to writer:
for (Cell c : kvs) {
KeyValue kv = KeyValueUtil.ensureKeyValue(c);
if (kv.getMvccVersion() <= smallestReadPoint) {
kv.setMvccVersion(0);
}
writer.append(kv);
++progress.currentCompactedKVs;
// check periodically to see if a system stop is requested
if (closeCheckInterval > 0) {
bytesWritten += kv.getLength();
if (bytesWritten > closeCheckInterval) {
bytesWritten = 0;
if (!store.areWritesEnabled()) {
progress.cancel();
return false;
}
}
}
}
kvs.clear();
} while (hasMore);
progress.complete();
return true;
}
/**
* @param store store
* @param scanners Store file scanners.
* @param scanType Scan type.
* @param smallestReadPoint Smallest MVCC read point.
* @param earliestPutTs Earliest put across all files.
* @return A compaction scanner.
*/
protected InternalScanner createScanner(Store store, List<StoreFileScanner> scanners,
ScanType scanType, long smallestReadPoint, long earliestPutTs) throws IOException {
Scan scan = new Scan();
scan.setMaxVersions(store.getFamily().getMaxVersions());
return new StoreScanner(store, store.getScanInfo(), scan, scanners,
scanType, smallestReadPoint, earliestPutTs);
}
/**
* @param store The store.
* @param scanners Store file scanners.
* @param smallestReadPoint Smallest MVCC read point.
* @param earliestPutTs Earliest put across all files.
* @param dropDeletesFromRow Drop deletes starting with this row, inclusive. Can be null.
* @param dropDeletesToRow Drop deletes ending with this row, exclusive. Can be null.
* @return A compaction scanner.
*/
protected InternalScanner createScanner(Store store, List<StoreFileScanner> scanners,
long smallestReadPoint, long earliestPutTs, byte[] dropDeletesFromRow,
byte[] dropDeletesToRow) throws IOException {
Scan scan = new Scan();
scan.setMaxVersions(store.getFamily().getMaxVersions());
return new StoreScanner(store, store.getScanInfo(), scan, scanners, smallestReadPoint,
earliestPutTs, dropDeletesFromRow, dropDeletesToRow);
}
}